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Budka, Anna, Dariusz Kayzer, Janina Zbierska, Klaudia Borowiak, Danuta Barałkiewicz, and Anetta Hanć. "Canonical Variate Analysis of Chlorophyll Content in Plants Exposed to Different Lead Concentrations in Ambient Air Conditions/ Analiza Zmiennych Kanonicznych Zawatości Chlorofilu W Roślinach Eksponowanych Na Różne Stężenia Ołowiu W Powietrzu Atmosferycznym." Civil And Environmental Engineering Reports 14, no. 3 (September 1, 2014): 15–26. http://dx.doi.org/10.1515/ceer-2014-0022.
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Streszczenie Praca prezentuje rezultaty biomonitoringu ołowiu w zróżnicowanych warunkach środowiskowych. Do oceny zawartości poziomu ołowiu wykorzystano rośliny życicy wielokwiatowej. Dodatkowo w liściach oznaczono zawartość chlorofilu (a+b, a oraz b) w świeżej masie. Rośliny eksponowano w okresie wegetacyjnym roku 2011 na pięciu stanowiskach badawczych różniących się parametrami środowiskowymi oraz w warunkach kontrolnych. Rośliny eksponowano w 28-dniowych okresach badawczych. Wyniki zawartości Pb oraz poziomów chlorofili w różnych miejscach ekspozycyjnych oraz seriach testowano z zastosowaniem wielowymiarowej analizy wariancji. Wykazano zmienność zawartości Pb oraz poziomów wszystkich form chlorofilu w różnych miejscach ekspozycyjnych i seriach. Najniższe zawartości ołowiu oraz najwyższe poziomy wszystkich form chlorofilu zaobserwowano na stanowisku podmiejskim. W pracy wykazano przydatność analizy zmiennych kanonicznych do graficznej prezentacji wyników biomonitoringu powietrza.
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Zalewska, Martyna, and Zbigniew Tukaj. "Biochemiczne i fizjologiczne aspekty rozkładu barwników chlorofilowych." Postępy Biochemii 65, no. 2 (June 6, 2019): 128–34. http://dx.doi.org/10.18388/pb.2019_261.
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Procesowi starzenia się liści i dojrzewania owoców towarzyszy rozkład chlorofilu do niefluorescencyjnych katabolitów (NCC). Ścieżkę rozpadu rozpoczynają reakcje redukcji w chloroplaście, w wyniku których cząsteczki chlorofilu b przekształcane są do chlorofilu a. Następnie, specyficzna dechelataza i esteraza usuwają atom magnezu i łańcuch fitolu w wyniku czego powstaje feoforbid a. W kolejnym kroku oksygenaza feoforbidu a oraz reduktaza czerwonego katabolitu dokonują otwarcia makropierścienia porfirynowego. Produktem tej przemiany jest wczesny fluorescencyjny katabolit (pFCC), który po hydroksylacji i innych specyficznych dla gatunku modyfikacjach trafia do wakuoli. W kwaśnym pH we wnętrzu tego organellum zachodzi izomeryzacja pFCC do bezbarwnych NCC, końcowych produktów rozkładu chlorofilu u roślin wyższych. Brak jest nadal odpowiedzi na szereg pytań dotyczących losów i znaczenia milionów ton produktów rozpadu chlorofilu, corocznie uwalnianych w środowisku wodnym w wyniku obumierania komórek fitoplanktonu. Nieliczne doniesienia wskazują, że glony i cyjanobakterie mogą metabolizować swoje kluczowe barwniki fotosyntetyczne w podobny sposób do roślin wyższych, jednak do tej pory dokładny przebieg rozkładu chlorofili u tych organizmów nie został poznany.
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Picchioni, G. A., S. Miyamoto, and J. B. Storey. "Growth and Boron Uptake of Five Pecan Cultivar Seedlings." HortScience 26, no. 4 (April 1991): 386–88. http://dx.doi.org/10.21273/hortsci.26.4.386.
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Growth and B uptake of five pecan [Carya illinoensis (Wangenh.) C. Koch] seedling cultivars were evaluated in two greenhouse experiments. Seedlings were exposed for 7 to 8 months to various B-containing irrigation solutions. In one study, the growth of `Apache', `Riverside', and `Burkett' seedlings declined significantly with a 5.0-mg B/liter application that provided 12.3 mg B/liter in the soil saturation extract. In the second study, B application of 2.5 mg·1iter-1 (6.4 mg·liter-1 in the saturation extract) reduced growth of `Western' and Wichita' seedlings. Seedling sources differed in susceptibility to B applications. `Apache' and `Wichita' seedlings were the more sensitive cultivars in the experiments. Leaf B concentrations increased linearly with concentrations in the saturation extract (r = 0.96 to 0.99), but did not depend on the cultivar. Boron toxicity (leaf interveinal chlorosis and tip necrosis) occurred within several weeks following B application of 1.25 to 2.5 mg·liter-1 (2.8 to 6.6 mg·liter-1 in the saturation extract, depending on cultivar). Three months later, chlorotic areas became necrotic in leaves containing >900 mg B/kg dry weight. Severe necrosis and some defoliation occurred when B concentrations were increased further. Leaves with no injury contained ≤325 mg B/kg.
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Oren, R., K. S. Werk, N. Buchmann, and R. Zimmermann. "Chlorophyll–nutrient relationships identify nutritionally caused decline in Piceaabies stands." Canadian Journal of Forest Research 23, no. 6 (June 1, 1993): 1187–95. http://dx.doi.org/10.1139/x93-150.
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Increasing needle chlorosis at a declining Piceaabies (L.) Karst. site in northeast Bavaria, Germany, as well as in other declining P. abies stands in southern Germany, was associated with a decrease in the concentrations of both chlorophyll a and b, and, to a lesser extent, of carotenoids. Needle chlorosis related more to a decrease in the chlorophyll concentration than to a decrease in the ratio of total chlorophyll to carotenoids. In forests growing on relatively acidified soils, concentrations of both chlorophyll a and b, and of carotenoids in chlorotic needles were related only to foliar magnesium concentration. In forests growing on more alkaline soils, chlorophyll concentration increased with potassium and phosphorus concentrations and decreased with calcium and magnesium concentrations. Green needles from a declining site in northeast Bavaria were also compared with those from a nearby healthy site. The chlorophyll concentrations in needles increased more at the healthy site than at the declining site during the growing season and with increasing needle age as predicted by a nutritional disharmony model. The use of foliar chlorophyll and nutrient analyses of needles representing a range in severity of chlorosis is proposed as a quick method of identifying the soil processes which, in some areas, cause forest decline.
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Dell, B., and N. Malajczuk. "Boron deficiency in eucalypt plantations in China." Canadian Journal of Forest Research 24, no. 12 (December 1, 1994): 2409–16. http://dx.doi.org/10.1139/x94-311.
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Boron deficiency is identified as one of the more important causes of poor stem form and malformed leaves in plantations of Eucalyptusglobulus in Yunnan Province, and of Eucalyptusgrandis, Eucalyptustereticornis, and Eucalyptusurophylla in Guandong Province. Symptoms of B deficiency in E. globulus were rolled and malformed leaves, stem dieback, and a prostrate form. In E. urophylla, leaf margins became chlorotic then necrotic, leaves turned brittle and corky, shoots died back, and the upper stem nodes were enlarged supporting numerous short-lived axillary shoots. In E. grandis, stem dieback was preceded by the basipetal accumulation of anthocyanin in leaves. Boron-deficient E. tereticornis leaves developed marginal and interveinal chlorosis and recurved margins. Depressed foliar B concentrations were associated with visible symptoms. In E. globulus, the mean B concentration in young leaves of healthy trees was 31 mg/kg dry matter compared with 10 mg/kg in prostrate trees. Symptoms did not appear in E. globulus trees supplied with B fertilizer at planting. Normal shoot growth was restored in E. urophylla by the addition of B to the soil.
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WAGA, ANNA MARIA, DOROTA JADCZAK, and AGNIESZKA ŻURAWIK. "Ocena wartości biologicznej owoców wybranych odmian papryki rocznej." Annales Horticulturae 29, no. 3 (February 20, 2020): 5–13. http://dx.doi.org/10.24326/ah.2019.3.1.
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Celem badań była ocena suchej masy oraz zawartości wybranych związków biologicznie czynnych w owocach wybranych odmian papryki rocznej. W ramach badań wykonano dwa doświadczenia. Rośliny uprawiano w tunelu foliowym. Materiał doświadczalny w pierwszym doświadczeniu stanowiło dziesięć słodkich odmian papryki: ‘Indus’ F1, ‘CRX66131’ F1, ‘Remus’ F1, ‘CRX61035’ F1, ‘CRX63134’ F1, ‘CRX63135’ F1, ‘CRX63142’ F1, ‘Kurtovska Kapiya’, ‘Delikates’, ‘Oda’. W doświadczeniu drugim przebadano pięć ostrych odmian papryki: dwie odmiany z grupy Habanero, o owocach żółtych i pomarańczowych, oraz trzy odmiany z grupy Fireflame, o owocach żółtych, pomarańczowych i czerwonych. Analizy chemiczne w powietrznie suchym surowcu obejmowały oznaczenie: suchej masy, zawartość chlorofilu a, b i chlorofilu ogółem oraz zawartości karotenoidów ogółem. Wykazano różnice składu chemicznego w zawartości poszczególnych składników chemicznych w surowcu u różnych odmian. Wśród badanych słodkich odmian papryki najwięcej chlorofilu a oznaczono w owocach odmian ‘CRX66131’ F1, ‘CRX61035’ F1, ‘Remus’ F1 oraz ‘CRX63134’ F1. Nie wykazano istotnych różnic w zawartości chlorofilu b w owocach badanych odmian papryki słodkiej. Owoce odmiany ‘CRX61035’ F1 charakteryzowały się największą zawartością chlorofilu ogółem. Największą zawartością karotenoidów ogółem charakteryzował się surowiec odmiany ‘Delikates’. Owoce tej odmiany wyróżniały się także istotnie większą suchą masą. Spośród porównywanych ostrych odmian papryki większą suchą masą odznaczał się surowiec papryki ‘Fireflame’ o owocach pomarańczowych. Wykazano istotne różnice w zawartości chlorofilu a, b oraz chlorofilu ogółem w surowcu badanych odmian. Istotnie większą wartością biologiczną owoców, ze względu na dużą zawartość chlorofilu a i chlorofilu ogółem, odznaczał się surowiec ‘Fireflame’ o owocach pomarańczowych. W nim także oznaczono największą zawartość chlorofilu b. Największą zawartością karotenoidów ogółem charakteryzowała się odmiana ‘Fireflame’ o czerwonych owocach.
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Palmer, D. A., and C. L. Bender. "Effects of the pseudomonad phytotoxin coronatine on tomato leaf structure and ultrastructure." Proceedings, annual meeting, Electron Microscopy Society of America 53 (August 13, 1995): 862–63. http://dx.doi.org/10.1017/s0424820100140683.
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Coronatine is a non-host-specific phytotoxin produced by several members of the Pseudomonas syringae group of pathovars. The toxin acts as a virulence factor in P. syringae pv. tomato, allowing the organism to multiply to a higher population density and develop larger lesions than mutant strains unable to produce the toxin. The most prominent symptom observed in leaf tissue treated with coronatine is an intense spreading chlorosis; this has been attributed to a loss of chlorophylls a and b in tobacco. Coronatine's effects on membrane integrity and cell ultrastructure have not been previously investigated. The present study describes changes in tomato leaves in response to treatment with purified coronatine, infection by a coronatine-producing strain of P. syringae pv. tomato, and infection by a cor" mutant.In contrast to H2O-treated tissue, coronatine-treated tissue showed a diffuse chlorosis extending approximately 5 mm from the inoculation site. Leaf thickness, cell number, and cell dimensions were similar for both healthy and coronatine-treated, chlorotic tissue; however, the epidermal cell walls were consistently thicker in coronatine-treated leaves (Figs, la and lb).
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Kurniawati, Fitrianingrum, Gede Suastika, and Giyanto . "EKSPRESI GEN PROTEIN SELUBUNG TOMATO INFECTIOUS CHLOROSIS VIRUS PADA ESCHERICHIA COLI." JURNAL HAMA DAN PENYAKIT TUMBUHAN TROPIKA 15, no. 2 (March 25, 2016): 114. http://dx.doi.org/10.23960/j.hptt.215114-121.
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Expression of tomato infectious chlorosis virus coat protein gene on Escherichia coli. Tomato infectious chlorosis virus (TICV) is the causal agent of chlorotic disease of tomato. Detection of TICV can be carried out by RT-PCR and serological test. Titer of TICV in plant tissue is very low because TICV is limited to phloem. Serological detection of TICV requires antiserum which is not available in Indonesia. Producing antibody through cloning and coat protein gene (TICV CP gene) expression is a promising approach in producing antiserum. The objective of this study was to express TICV CP gene as antigen for antiserum production. TICV CP gene was amplified using RT-PCR from total RNA extracted from TICV infected leaves collected from Cipanas, Cianjur, West Java. The amplified CP gene was then sequenced and sub-cloned into pET 21b expression vector, transformed into Escherichia coli strain BL21 DE3(pLysS) and induced expression using IPTG 1 mM overnight at 37 °C. CP that contains 6xhistag was purified using NiNTAspin column and then confirmed by SDS-PAGE. The size of TICV CP gene was 750 bp and the gene was expressed on pET 21 b vector and SDS-PAGE showed a 29 kDa band.
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IGARASHI, MASAYUKI, YASUYUKI TETSUKA, YAYOI MIMURA, ATSUSHI TAKAHASHI, TSUYOSHI TAMAMURA, KIYOSHI SATO, HIROSHI NAGANAWA, and TOMIO TAKEUCHI. "AB5046A and B, novel chlorosis-inducing substances from Nodulisporium sp." Journal of Antibiotics 46, no. 12 (1993): 1843–48. http://dx.doi.org/10.7164/antibiotics.46.1843.
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Nie, Xianzhou, and Rudra P. Singh. "Differential Accumulation of Potato virus A and Expression of Pathogenesis-Related Genes in Resistant Potato cv. Shepody upon Graft Inoculation." Phytopathology® 91, no. 2 (February 2001): 197–203. http://dx.doi.org/10.1094/phyto.2001.91.2.197.
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Potato (Solanum tuberosum L.) cv. Shepody is highly resistant to Potato virus A (PVA), yielding no visible symptoms after rub inoculation. In ‘Shepody’ rootstocks graft-inoculated by PVA-infected scions from a susceptible host, we found a resistance consisting of traces of necrosis (necrotic streaks) in stems and chlorosis in newly emerged leaves. The response was temperature dependent, appearing at 15 to 18°C but not at 28 to 31°C. Necrosis was also observed in tubers, appearing first in the bud end and spreading randomly throughout the majority of the tuber. Trace amounts of PVA in plant tissues were detected by a combination of reverse transcription polymerase chain reaction and Southern blot procedures. The virus concentration was significantly higher in visibly necrotic areas than in nonnecrotic areas, suggesting that presence of the necrosis may be concentration dependent. Pathogenesis-related gene expression showed that chitinase A and B, glucanase B, and PR-10a were associated with chlorotic or necrotic symptoms in leaves, stems, and tubers. Gene expression was markedly more evident in tuber tissues than in leaves and stems. Furthermore, generation of oxidants was also observed within the necrotic areas. Although PVA was detected in necrotic areas of tubers, newly emerged plants from the same tubers were PVA-free.
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Kashif, M., S. Pietilä, K. Artola, R. A. C. Jones, A. K. Tugume, V. Mäkinen, and J. P. T. Valkonen. "Detection of Viruses in Sweetpotato from Honduras and Guatemala Augmented by Deep-Sequencing of Small-RNAs." Plant Disease 96, no. 10 (October 2012): 1430–37. http://dx.doi.org/10.1094/pdis-03-12-0268-re.
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Sweetpotato (Ipomoea batatas) plants become infected with over 30 RNA or DNA viruses in different parts of the world but little is known about viruses infecting sweetpotato crops in Central America, the center of sweetpotato domestication. Small-RNA deep-sequencing (SRDS) analysis was used to detect viruses in sweetpotato in Honduras and Guatemala, which detected Sweet potato feathery mottle virus strain RC and Sweet potato virus C (Potyvirus spp.), Sweet potato chlorotic stunt virus strain WA (SPCSV-WA; Crinivirus sp.), Sweet potato leaf curl Georgia virus (Begomovirus sp.), and Sweet potato pakakuy virus strain B (synonym: Sweet potato badnavirus B). Results were confirmed by polymerase chain reaction and sequencing of the amplicons. Four viruses were detected in a sweetpotato sample from the Galapagos Islands. Serological assays available to two of the five viruses gave results consistent with those obtained by SRDS, and were negative for six additional sweetpotato viruses tested. Plants coinfected with SPCSV-WA and one to two other viruses displayed severe foliar symptoms of epinasty and leaf malformation, purpling, vein banding, or chlorosis. The results suggest that SRDS is suitable for use as a universal, robust, and reliable method for detection of plant viruses, and especially useful for determining virus infections in crops infected with a wide range of unrelated viruses.
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Simko, Ivan, Jan H. van den Berg, Dick Vreugdenhil, and Elmer E. Ewing. "Mapping loci for chlorosis associated with chlorophyll b deficiency in potato." Euphytica 162, no. 1 (October 17, 2007): 99–107. http://dx.doi.org/10.1007/s10681-007-9595-z.
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Gamarra, Heidy A., Segundo Fuentes, Francisco J. Morales, Rachel Glover, Chris Malumphy, and Ian Barker. "Bemisia afer sensu lato, a Vector of Sweet potato chlorotic stunt virus." Plant Disease 94, no. 5 (May 2010): 510–14. http://dx.doi.org/10.1094/pdis-94-5-0510.
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Bemisia tabaci biotype B is considered to be the primary vector of Sweet potato chlorotic stunt virus (SPCSV, Crinivirus). However, Trialeurodes abutiloneus also has been shown to transmit SPCSV in a semipersistent manner. Mixed infection of SPCSV with the aphid-transmitted Sweet potato feathery mottle virus (SPFMV, Potyvirus) causes sweetpotato (Ipomoea batatas) virus disease (SPVD), the major virus disease affecting this crop. High populations of B. afer sensu lato are seasonally associated with sweetpotato in Peru during times of low B. tabaci incidence. The transmission of SPCSV (in single and double infection with SPFMV) by laboratory-reared B. afer sensu lato and B. tabaci biotype B was investigated. For SPCSV transmission efficiency, individual adult insects were allowed 48 h for acquisition and inoculation access periods at both 20 and 25°C. SPCSV was transmitted by both whiteflies, with similar transmission efficiency when the virus was acquired from plants singly infected by SPCSV or doubly infected with SPCSV and SPFMV, at 20 and 25°C. We conclude that B. afer sensu lato is a newly identified vector of SPCSV. This finding may have important epidemiological significance for the spread of SPCSV and SPVD.
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Okuda, Mitsuru, Shinichiro Okazaki, Shuichi Yamasaki, Shiori Okuda, and Mitsuhiro Sugiyama. "Host Range and Complete Genome Sequence of Cucurbit chlorotic yellows virus, a New Member of the Genus Crinivirus." Phytopathology® 100, no. 6 (June 2010): 560–66. http://dx.doi.org/10.1094/phyto-100-6-0560.
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Cucurbit chlorotic yellows virus (CCYV) causes chlorotic yellows on cucumber (Cucumis sativus) and melon (Cucumis melo) and is transmitted by Bemisia tabaci biotype B and Q whiteflies. To characterize the host range of CCYV, 21 cucurbitaceous and 12 other plant species were inoculated using whitefly vectors. All tested Cucumis spp. except Cucumis anguria and Cucumis zeyheri were systemically infected with CCYV, although infection rates varied among species. Citrullus lanatus, Cucurbita pepo, and Luffa cylindrica were susceptible to CCYV; however, the infection rates were low and symptoms were unclear. In addition to the cucurbitaceous plants, Beta vulgaris, Chenopodium amaranticolor, Chenopodium quinoa, Spinacia oleracea, Lactuca sativa, Datura stramonium, and Nicotiana benthamiana were also systemically infected by CCYV. Complete RNA1 and RNA2 were reverse-transcribed, cloned, and sequenced. CCYV RNA1 was found to be 8,607 nucleotides (nt) long and contained four open reading frames (ORFs). The first ORF spanned methyltransferase and RNA helicase domains followed by an RNA-dependent RNA polymerase domain, presumably translated by a +1 ribosomal frameshift. CCYV RNA2 was found to be 8,041 nt long and contained eight ORFs, including the hallmark gene array of the family Closteroviridae. Phylogenetic analysis demonstrated that CCYV was genetically close to Lettuce chlorosis virus, Bean yellow disorder virus, and Cucurbit yellow stunting disorder virus. Amino acid sequence similarities of representative proteins with these viruses indicated that CCYV should be classified as a distinct crinivirus species.
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Gruber, Bernd, and Harald Kosegarten. "Depressed growth of non-chlorotic vine grown in calcareous soil is an iron deficiency symptom prior to leaf chlorosis." Journal of Plant Nutrition and Soil Science 165, no. 1 (February 2002): 111. http://dx.doi.org/10.1002/1522-2624(200202)165:1<111::aid-jpln111>3.0.co;2-b.
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Brown, J. K., Kristin M. Ostrow, Ali M. Idris, and Drake C. Stenger. "Chino del tomate virus:Relationships to Other Begomoviruses and Identification of A-Component Variants that Affect Symptom Expression." Phytopathology® 90, no. 5 (May 2000): 546–52. http://dx.doi.org/10.1094/phyto.2000.90.5.546.
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Phylogenetic and distance analyses place Chino del tomate virus (CdTV) in the New World clade of begomoviruses and indicate that CdTV and Tomato leaf crumple virus (TLCrV) are closely related strains of the same virus. One cloned CdTV A component (pCdTV-H6), when inoculated to tomato with the B component (pCdTV-B52), produced mild symptoms and low DNA titers. Another cloned CdTV A component (pCdTV-H8), when coinoculated to tomato with the B component, produced moderate leaf curling and veinal chlorosis similar to that of TLCrV. Coinoculation of both CdTV A components and the B component to tomato produced wild-type chino del tomate (CdT) disease symptoms consisting of severe leaf curling, veinal and interveinal chlorosis, and stunting. The two CdTV A components were nearly identical, except at nucleotide positions 1,722 and 2,324. The polymorphism at nucleotide 1,722 resulted in a change at Rep amino acid 261. The second polymorphism at nucleotide 2,324 resulted in changes at Rep amino acid 60 and AC4 amino acid 10. Two chimeric A components constructed by reciprocal exchange of a fragment bearing the polymorphic site at nucleotide 1,722 were evaluated for symptom phenotype. One chimeric A component (pCdTV-H86) produced wild-type CdT symptoms when coinoculated to tomato with the B component. The reciprocal chimeric A component (pCdTV-H68), when coin-oculated to tomato with the B component, also produced severe leaf curling, veinal chlorosis, and stunting. However, pCdTV-H68 induced less obvious interveinal chlorosis than wild-type or pCdTV-H86. Examination of A component genotypes recovered from tomato coinoculated with pCdTV-H6 and pCdTV-H8 indicated that recombination occurred to produce a genotype identical to pCdTV-H86. These results indicate that subtle genotypic variation has significant effects on symptom expression and may explain phenotypic differences observed among isolates and cloned DNAs of CdTV and TLCrV.
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Huang, Liping, Xiaobin Shi, Jizhe Shi, Zhuo Zhang, Yong Fang, Zhanhong Zhang, Qiuyi Pan, et al. "Tomato Chlorosis Virus Infection Facilitates Bemisia tabaci MED Reproduction by Elevating Vitellogenin Expression." Insects 12, no. 2 (January 25, 2021): 101. http://dx.doi.org/10.3390/insects12020101.
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Transmission of plant pathogenic viruses mostly relies on insect vectors. Plant virus could enhance its transmission by modulating the vector. Previously, we showed that feeding on virus infected plants can promote the reproduction of the sweet potato whitefly, Bemisia tabaci MED (Q biotype). In this study, using a whitefly-Tomato chlorosis virus (ToCV)-tomato system, we investigated how ToCV modulates B. tabaci MED reproduction to facilitate its spread. Here, we hypothesized that ToCV-infected tomato plants would increase B. tabaci MED fecundity via elevated vitellogenin (Vg) gene expression. As a result, fecundity and the relative expression of B. tabaci MED Vg was measured on ToCV-infected and uninfected tomato plants on days 4, 8, 12, 16, 20 and 24. The role of Vg on B. tabaci MED reproduction was examined in the presence and absence of ToCV using dietary RNAi. ToCV infection significantly increased B. tabaci MED fecundity on days 12, 16 and 20, and elevated Vg expression on days 8, 12 and 16. Both ovarian development and fecundity of B. tabaci MED were suppressed when Vg was silenced with or without ToCV infection. These combined results suggest that ToCV infection increases B. tabaci MED fecundity via elevated Vg expression.
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Mińkowski, Karol, Monika Bartosiak, and Dariusz Ciemiński. "Wpływ barwników chlorofilowych na przebieg utleniania fotosensybilizowanego oleju rzepakowego." Zywnosc Nauka Technologia Jakosc/Food Science Technology Quality 126, no. 1 (2021): 116–32. http://dx.doi.org/10.15193/zntj/2021/126/372.
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Obecność barwników chlorofilowych w olejach ma negatywny wpływ na ich smak, zapach, barwę, przejrzystość, stabilność termiczną i okres trwałości. Związki te są silnymi fotosensybilizatorami procesów utleniania nienasyconych wiązań lipidów, co niekorzystnie wpływa na stabilność oksydacyjną oleju w trakcie przechowywania. Celem pracy była ocena aktywności fotooksydacyjnej barwników chlorofilowych w oleju rzepakowym pod wpływem promieniowania UV-A. Materiałem do badań był rafinowany olej rzepakowy oraz jego triacyloglicerole (TAG). Jako fotosensybilizatory stosowano chlorofil a oraz feofitynę a. Kontrolę procesu fotooksydacji prowadzono poprzez oznaczanie zawartości tlenu singletowego, związków lotnych oraz barwników chlorofilowych. Wykazano, że barwniki chlorofilowe są fotosensybilizatorami fotoutleniania oleju rzepakowego oraz TAG podczas ich ekspozycji na promieniowanie UV-A. Chlorofil a i feofityna a biorą udział w procesie generowania tlenu singletowego. Efektywność fotosensybilizująca chlorofilu a jest wyższa niż feofityny a. Barwniki chlorofilowe mają zróżnicowany wpływ na zawartość i profil substancji lotnych powstających podczas fotoutleniania oleju oraz TAG. Rodzaj fotosensybilizatora ma istotny wpływ na zawartość substancji lotnych ogółem oraz heksanalu w TAG. Maksymalna zawartości substancji lotnych występuje przy dawce fotosensybilizatora na poziomie 0,5 mg/kg. Barwniki chlorofilowe ulegają degradacji w wyniku utleniania tlenem singletowym podczas fotooksydacji oleju rzepakowego i TAG. Feofityna a trudniej ulega degradacji niż chlorofil a. Substancje towarzyszące odgrywają ważną rolę ochronną przed fotoutlenianiem oleju rzepakowego. Ich usunięcie przyczynia się do większego pobrania tlenu singletowego, przyrostu zawartości substancji lotnych ogółem, zmian ich profilu oraz zwiększonej degradacji barwników chlorofilowych. Barwniki chlorofilowe wywierają niekorzystny wpływ na stabilność oksydacyjną oleju rzepakowego podczas jego ekspozycji na promieniowanie UV-A i powinny być z niego usunięte.
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Úrbez-Torres, J. R., W. D. Gubler, H. Peláez, Y. Santiago, C. Martín, and C. Moreno. "Occurrence of Botryosphaeria obtusa, B. dothidea, and B. parva Associated with Grapevine Trunk Diseases in Castilla y León Region, Spain." Plant Disease 90, no. 6 (June 2006): 835. http://dx.doi.org/10.1094/pd-90-0835a.
Full textAbstract:
Between 2000 and 2004, 176 vineyards were surveyed for disease symptoms throughout the main grapevine-production areas of Bierzo, Cigales, Ribera del Duero, Rueda, and Toro in the Castilla y León region of Spain. Symptoms resembling Eutypa dieback, such as stunted chlorotic shoots, deformed leaves with necrotic areas, and typical wedge-shaped cankers in the wood, were observed in 80% of surveyed vineyards. The second most common disease observed was esca. The mild form of esca, interveinal chlorosis or reddened patterns on the leaves, was observed in 35% of surveyed vineyards. Severe esca symptoms that include sudden defoliation of some or all parts of the vine followed by shriveling of fruit clusters were observed in vineyards during very hot and dry summer periods. Wood from vines with esca was yellowish, soft, and often partially or completely surrounded by necrotic wood. Black vascular streaking in the wood was also observed in some vines with esca. Samples of wood from vines with symptoms of Eutypa dieback or esca were collected from different cultivars (Tempranillo, Cabernet Sauvignon, Mencía, Garnacha, Viura, and Verdejo). Small pieces of symptomatic wood were placed on 4% potato dextrose agar amended with tetracycline hydrochloride (0.01%) (PDA-tet) and incubated at room temperature. Pure cultures were obtained by excising hyphal tips and transferring to PDA-tet. Species of Botryosphaeria were most frequently isolated from wedge-shaped cankers as well as from wood with necrosis or black vascular streaking. Botryosphaeria spp. also were isolated from the soft yellowish wood, however, Fomitiporia punctata, Stereum hirsutum, and Phaeoacremonium spp. were the most common fungi associated with this symptom. On the basis of morphological characteristics in culture (1), three species were isolated (B. obtusa, B. dothidea, and B. parva). Colonies of B. obtusa were green to dark green with moderate aerial mycelium. Pycnidia developed after 6 days and conidia (n = 50) measured 19 to 27 × 9 to 17 μm and were hyaline and light brown, becoming dark brown when mature, mostly aseptate, and rounded in shape. Colonies of B. dothidea were white, becoming dark green with age and with copious aerial mycelium. Pycnidia started to develop after 10 days, and conidia measured 17 to 31 × 4 to 8 μm, were hyaline, aseptate, and fusiform in shape. Colonies of B. parva were similar in appearance to those of B. dothidea but pycnidia developed after 5 weeks. Conidia measured 11 to 21 × 4 to 9 μm, were hyaline when immature, becoming light brown with two septa with age, and ellipsoidal in shape. Identity of the three Botryosphaeria species was confirmed by comparing morphology with growth of the following identified California isolates: B. obtusa (UCD352Mo and UCD666Na), B. dothidea (UCD1066So), and B. parva (UCD642So) and by comparing sequences of the internal transcribed spacer region (ITSI-5.8S-ITS2) rDNA, and a partial sequence of the β-tubulin gene (BT2) of our isolates with those of previously identified and sequenced isolates deposited in GenBank. Sequences of B. obtusa (UCD343Spa, UCD461Spa, UCD468Spa, and UCD621Spa), B. dothidea (UCD303Spa), and B. parva (UCD577Spa and UCD578Spa) were deposited in GenBank. To our knowledge, this is the first report of B. obtusa, B. dothidea, and B. parva on grapevines in the Castilla y León region in Spain. Reference: (1) A. J. L. Phillips. Phytopathol. Mediterr. 41:3, 2002.
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Wintermantel, William M., and Gail C. Wisler. "Vector Specificity, Host Range, and Genetic Diversity of Tomato chlorosis virus." Plant Disease 90, no. 6 (June 2006): 814–19. http://dx.doi.org/10.1094/pd-90-0814.
Full textAbstract:
Tomato chlorosis virus (ToCV), family Closteroviridae, genus Crinivirus, causes interveinal chlorosis, leaf brittleness, and limited necrotic flecking or leaf bronzing on tomato leaves. ToCV can cause a decline in plant vigor and reduce fruit yield. It is emerging as a serious production problem for field and greenhouse tomato growers, and has been increasing in prevalence in many parts of the world. The virus is unique among known whitefly-transmitted viruses, due to its ability to be transmitted by four whitefly vectors from two genera. Studies demonstrated that transmission efficiency and virus persistence in the vector varies significantly among the different whitefly vectors. Trialeurodes abutilonea and Bemisia tabaci biotype B are highly efficient vectors of ToCV. B. tabaci biotype A and T. vaporariorum are less efficient vectors, but are fully capable of transmission. ToCV persists for up to 5 days in T. abutilonea, 2 days in B. tabaci biotype B, and only 1 day in B. tabaci biotype A and T. vaporariorum. ToCV has a moderately wide host range, infecting 24 host plant species in seven families. A portion of the coat protein coding region of five geographically diverse ToCV isolates was compared and found to be highly conserved. This information, coupled with existing information on conservation within the heat shock protein 70 homologue coding region, suggests that many ToCV isolates throughout the world are related very closely, and may have been distributed on plant material.
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Kirti, P. B., S. B. Narasimhulu, T. Mohapatra, S. Prakash, and V. L. Chopra. "Correction of chlorophyll deficiency in alloplasmic male sterile Brassica juncea through recombination between chloroplast genomes." Genetical Research 62, no. 1 (August 1993): 11–14. http://dx.doi.org/10.1017/s0016672300031505.
Full textAbstract:
SummaryBrassica juncea cv. Pusa Bold carrying B. oxyrrhina cytoplasm (oxy cytoplasm) was male sterile and chlorotic under field conditions at low temperature (Prakash & Chopra, 1990). Leaf protoplasts of the chlorotic male sterile alloplasmic line (2n = 36) were fused with hypocotyl protoplasts of green male fertile, B. juncea cv. RLM-198 (2n = 36) using polyethylene glycol. Of the 1043 plants regenerated from 10 fusion experiments, 123 had ‘gigas’ features and were identified as presumptive fusion products. Among field-grown population, one plant was dark green even at low temperatures and male sterile. It possessed 72 chromosomes which formed 36 bivalents at late diakinesis of meiosis-I. This plant was back-crossed to B. juncea cv. Pusa Bold (the maintainer line) for three successive generations. One male sterile, normal green BC3 progeny plant with 2n = 36 was analyzed for organelle constitution. Probing its total DNA with the mitochondrial gene for cytochrome oxidase subunit I revealed that it possessed mitochondria of B. oxyrrhina. Southern hybridization pattern with the gene for ribulose bisphosphate carboxylase oxygenase-large subunit (rbcL) revealed that the chloroplast genome of the chlorophyll deficiencycorrected plant had characteristics of both B. juncea and B. oxyrrhina. The deficiency correction has been attributed to recombination between chloroplast genomes of the two species.
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Petrazzini, Lauro L., Guilherme A. Souza, Cléber L. Rodas, Eduardo B. Emrich, Janice G. Carvalho, and Rovilson J. Souza. "Nutritional deficiency in crisphead lettuce grown in hydroponics." Horticultura Brasileira 32, no. 3 (September 2014): 310–13. http://dx.doi.org/10.1590/s0102-05362014000300012.
Full textAbstract:
The identification of nutrient deficiency symptoms in lettuce helps both producers and technical staff to keep the plant nutritional balance in their producing areas. The objective of this study was to evaluate production and describe and record the visual symptoms caused by the isolated or combined shortage of K, Ca, B and Zn in crisphead lettuce grown in hydroponics. The experimental design was completely randomized blocks with four replications and eight treatments, representing the single (K, Ca, B, Zn) and combined (Ca and B, K and Zn, B and Zn) omission of nutrients, with a control treatment containing a complete nutrient solution. We used the crisphead lettuce cultivar Rider Plus. Under Ca shortage, plant growth was reduced and chlorosis appeared in the borders of young leaves. K shortage was the most detrimental to production of shoot fresh and dry matter and root dry matter. Where B was absent, plant growth was limited, the apical dominance was lost and leaves became wrinkled. Plants without Zn showed mild chlorosis in the blade of young leaves, elongation and bending of petioles and reduction in root density. The combined omission of Ca and B slowed down plant growth and induced necrosis at the borders of young leaves, while the combined omission of K and Zn initially induced K deficiency symptoms with reduced growth. When B and Zn were simultaneously subtracted, plants first showed B deficiency symptoms: reduction in plant size as compared to the control treatment and death of the apical bud.
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Cuadrado, I. M., D. Janssen, L. Velasco, L. Ruiz, and E. Segundo. "First Report of Cucumber vein yellowing virus in Spain." Plant Disease 85, no. 3 (March 2001): 336. http://dx.doi.org/10.1094/pdis.2001.85.3.336a.
Full textAbstract:
In the autumn of 2000, an outbreak of a disease caused considerable losses in greenhouse cucumber crops in Almeria (Spain). Infected plants showed vein clearing followed by chlorosis in leaves and yellow/green chlorotic spots on fruits. These symptoms as well as the presence of Bemisia tabaci in the crops suggested the possible involvement of Cucumber vein yellowing virus (CVYV), a proposed member of the Potiviridae family, which was first described in 1960 in Cucumis spp. from Israel (1). B. tabaci populations and leaves from cucumber plants were collected from the greenhouses and analyzed by RT-PCR using specific primers (CV(+): 5′-AGCTAGCGCGTATGGGGTGAC-3′; CV(-): 5′-GCGCCGCAAGTGCAA-ATAAAT-3′) that we designed based on the partial sequence published for CVYV (2). Total nucleic acid extracts from both B. tabaci individuals and the collected plants yielded amplification products of the expected size (449 bp), which were cloned and sequenced (Genebank accession number AJ301640). The sequence was 95.6% identical to that previously reported for CVYV. Nonviruliferous B. tabaci whiteflies were given a 24-h acquisition period on symptomatic leaves and then placed in groups of 15 insects on each of 10 healthy cucumber plants at the 4 leaf-stage for a 24-h inoculation period. Inoculated and control plants were analyzed 1 week later and the infection with CVYV was confirmed (10/10) by RT-PCR. Doublestranded RNA extractions from field-collected samples and from plants inoculated under controlled conditions suggested that no dsRNA formation was associated with the infection. This is the first report of CVYV in Spain. References: (1) S. Cohen and F. E. Nitzany. Phytopathol. Medit. 1:44, 1960. (2) H. Lecoq et al. J. Gen. Virol. 81:2289, 2000.
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Sim, J., R. A. Valverde, and C. A. Clark. "Whitefly Transmission of Sweetpotato chlorotic stunt virus." Plant Disease 84, no. 11 (November 2000): 1250. http://dx.doi.org/10.1094/pdis.2000.84.11.1250c.
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The genus Crinivirus of the plant virus family Closteroviridae include members that are bipartite and whitefly-transmitted (2). The Crinivirus, Sweetpotato chlorotic stunt virus (SPCSV), was described from sweetpotato (Ipomoea batatas) in Nigeria (1). Vector transmission studies of SPCSV were conducted using two whitefly species, the sweetpotato whitefly (Bemisia tabaci biotype B) and the bandedwinged whitefly (Trialeurodes abutilonea). Whitefly colonies were reared in the laboratory on cotton plants in plexiglass cages. To evaluate transmission efficiency, single whiteflies were used in all experiments. Whiteflies were given 2-day acquisition access periods on I. batatas cv. White Bunch co-infected with SPCSV and Sweetpotato feathery mottle virus (SPFMV). Single whiteflies were then placed on individual healthy I. nil cv. Scarlet O'Hara seedlings for 2-day inoculation access periods. Plants then were sprayed with imidacloprid insecticide and placed in the greenhouse. Four independent tests were performed with each whitefly species. Seven to 10 days after exposing test plants to B. tabaci, 6 of 35, 4 of 28, 5 of 30, and 3 of 25 I. nil plants showed symptoms that consisted of leaf distortion and yellowing. In similar experiments conducted with T. abutilonea, 1 of 33, 0 of 32, 1 of 30, and 2 of 28 I. nil plants showed symptoms. Two weeks after inoculations, reverse transcription- polymerase chain reaction assays were performed with all 22 symptomatic and five randomly selected symptomless plants using primers that amplify the SPCSV heat shock protein 70 (HSP70) homolog gene fragment (446 bp). All 22 symptomatic plants were positive while the five symptomless plants tested were negative. Lower transmission rates were obtained with T. abutilonea (3.2%) when compared with B. tabaci (15.2%). These two whiteflies are present in sweetpotato fields in Louisiana and may play an important role in the spread of SPCSV. This represents the first report of transmission of SPCSV by the bandedwinged whitefly References: (1) S. Winter et al. Phytopathology 82:869–875, 1992. (2) G. C. Wisler et al. Plant Dis. 82:270–280, 1998.
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Krizek, Donald T., Roman M. Mirecki, and Steven J. Britz. "Influence of Ambient UV-A and UV-B on Growth, Chlorosis, and Flavonoid Content of Cucumber." HortScience 30, no. 4 (July 1995): 898C—898. http://dx.doi.org/10.21273/hortsci.30.4.898c.
Full textAbstract:
The influence of ambient UV radiation on growth, chlorosis, and flavonoid content was examined in four cultivars of cucumber (`Ashley', `Poinsett', `Marketmore', and `Salad Bush'). Plants were grown from seed in UV exclusion chambers consisting of UV transmitting plexiglass (10% T, 285 nm), lined with 3- or 5-mil Llumar (10% T, 399 or 404 nm) to exclude UV-A and UV-B, 5-mil polyester (10%T, 319 nm) to exclude UVB, or cellulose acetate (10% T, 291 nm) to transmit UV-A and UV-B. Plants were grown in 15 cm plastic pots containing vermiculite and were fertilized daily with nutrient solution. Despite their differential sensitivity to supplemental UV-B radiation, all four cultivars responded similarly to the exclusion treatments. After 19 to 21 days, plants grown under ambient UV-A and UV-B generally had less stem, leaf, and root biomass and less total height and total leaf area than those grown under conditions in which UV-A and UV-B or only UV-B was excluded. Flavonoid content, leaf number, and floral development were unaffected by UV. These findings demonstrate the extreme sensitivity of cucumber to current levels of solar UV radiation.
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Peryea, Frank J. "1023 MANAGING BORON NUTRITION IN DECIDUOUS TREE FRUIT ORCHARDS." HortScience 29, no. 5 (May 1994): 575a—575. http://dx.doi.org/10.21273/hortsci.29.5.575a.
Full textAbstract:
Boron (B) is an essential micronutrient that is often in inadequate supply in many deciduous tree fruit orchards and must therefore be added as fertilizer. It can also occur at phytotoxic levels because of over-fertilization, use of high-B irrigation water, or naturally in arid soils that are natively high in B. Tree B status is usually characterized by leaf analysis although other diagnostic criteria are being evaluated. Several tests are used to characterize soil B status. Symptoms of B deficiency include blossom blast, poor fruit set and development, shortened internodes, terminal bud death, and shoot dieback. To ameliorate deficiency, B fertilizer may be broadcast or sprayed over the soil surface or sprayed on tree canopies. In some regions, maintenance applications of B fertilizer are made to prevent development of B deficiency. Sodium borates or orthoboric acid are usually used. Fertilizer rates and timing vary with location and farming practices. Symptoms of B excess include reduced or no yield, impaired fruit quality, leaf marginal chlorosis and necrosis, defoliation, and shoot dieback. Boron toxicity is alleviated by leaching B-enriched soil to move B below the root zone.
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Lavon, Ruth, Raphael Salomon, and Eliezer E. Goldschmidt. "Effect of Potassium, Magnesium, and Calcium Deficiencies on Nitrogen Constituents and Chloroplast Components in Citrus Leaves." Journal of the American Society for Horticultural Science 124, no. 2 (March 1999): 158–62. http://dx.doi.org/10.21273/jashs.124.2.158.
Full textAbstract:
The chlorotic appearance of mineral-deficient citrus leaves presumably reflects degradative changes in chloroplast components, most of which have nitrogen as a principal constituent. To examine this assumption the size of some major nitrogen pools, the SDS-PAGE pattern of soluble and chloroplast membranal proteins, and the activities of nitrate reductase and ribulose bisphosphate carboxylase (RuBPcase) were determined in leaves of rough-lemon (Citrus volkameriana Ten. & Pasq) plants grown hydroponically for 3 to 10 months under K, Mg, and Ca deficiencies. Plants grown under minerally deficient conditions produced less biomass. Leaves developing under K, Mg, and Ca-deficient conditions had significantly reduced concentrations of the respective elements. Chlorophyll levels of the chlorotic Mg and Ca-deficient leaves were lower than those of control leaves but chlorophyll a/b ratios were not markedly different. Calcium deficiency caused significant decreases in total nitrogen, nitrates, and the free amino acid pool. Proline which is the major component of the free amino acid pool decreased by 82.5%. Calcium-deficient leaves had significantly lower nitrate reductase and RuBPcase activities. The level of RuBPcase holoenzyme and its subunits were also reduced. Protein levels of K, Mg, and Ca-deficient leaves were not significantly altered. The SDS-PAGE patterns of soluble and chloroplast membranal proteins did not reveal major qualitative changes. In conclusion, the data do not demonstrate a general close link between chlorosis of minerally deficient citrus leaves and nitrogen metabolism. Calcium deficiency seems to specifically interfere with early stages of nitrogen assimilation and free amino acid accumulation but the metabolic integrity of the leaf is apparently maintained even under severe nutritional stress conditions.
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Dong, Fang, Yuanzhi Shi, Meiya Liu, Kai Fan, Qunfeng Zhang, and Jianyun Ruan. "iTRAQ-Based Quantitative Proteomics Analysis Reveals the Mechanism Underlying the Weakening of Carbon Metabolism in Chlorotic Tea Leaves." International Journal of Molecular Sciences 19, no. 12 (December 7, 2018): 3943. http://dx.doi.org/10.3390/ijms19123943.
Full textAbstract:
To uncover mechanism of highly weakened carbon metabolism in chlorotic tea (Camellia sinensis) plants, iTRAQ (isobaric tags for relative and absolute quantification)-based proteomic analyses were employed to study the differences in protein expression profiles in chlorophyll-deficient and normal green leaves in the tea plant cultivar “Huangjinya”. A total of 2110 proteins were identified in “Huangjinya”, and 173 proteins showed differential accumulations between the chlorotic and normal green leaves. Of these, 19 proteins were correlated with RNA expression levels, based on integrated analyses of the transcriptome and proteome. Moreover, the results of our analysis of differentially expressed proteins suggested that primary carbon metabolism (i.e., carbohydrate synthesis and transport) was inhibited in chlorotic tea leaves. The differentially expressed genes and proteins combined with photosynthetic phenotypic data indicated that 4-coumarate-CoA ligase (4CL) showed a major effect on repressing flavonoid metabolism, and abnormal developmental chloroplast inhibited the accumulation of chlorophyll and flavonoids because few carbon skeletons were provided as a result of a weakened primary carbon metabolism. Additionally, a positive feedback mechanism was verified at the protein level (Mg chelatase and chlorophyll b reductase) in the chlorophyll biosynthetic pathway, which might effectively promote the accumulation of chlorophyll b in response to the demand for this pigment in the cells of chlorotic tea leaves in weakened carbon metabolism.
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Al-Saleh, M. A., M. H. Ahmad, I. M. Al-Shahwan, J. K. Brown, and A. M. Idris. "First Report of Watermelon chlorotic stunt virus Infecting Watermelon in Saudi Arabia." Plant Disease 98, no. 10 (October 2014): 1451. http://dx.doi.org/10.1094/pdis-06-14-0583-pdn.
Full textAbstract:
In the Saudi Arabian deserts, watermelon [Citrullus lanatus (Thunb.)] is cultivated in the lowlands and wadis (washes) where water accumulates following rainfall, and where heat, salt, and drought stress are common constraints on production. During the spring of 2014, watermelon leaves exhibited yellowing and severe chlorotic mottling symptoms. The foliar symptoms were reminiscent of Watermelon chlorotic stunt virus (WmCSV), a bipartite begomovirus previously reported in several neighboring countries (1,3). Ten samples were collected from three farms in the Leith region, where 100% of the watermelon plants were symptomatic. Total nucleic acids were extracted from the symptomatic watermelon plants and were subjected to PCR using WmCSV DNA-A specific primers designed based on a complete genome sequence (GenBank Accession No. AJ012081), WmCSVF-3′-CGTGCTGTTGCCCCCACTGT-5′ and WmCSVR-3′-CCTGCATATCTCGTGCCAGAATC-5′ to obtain an expected size fragment of 1,111 bp located between the nucleotide (nt) coordinates 400-1510. The amplicons (one per sample) were cloned, and the DNA sequence was determined for each and used to search the NCBI database. The top hits for sequences obtained from all 10 samples were to WmSCV sequences, with shared nt identity values of 97 to 98%. To clone the full-length begomoviral DNA-A and DNA-B components, nucleic acids were subjected to rolling circle amplification (RCA) (2). The RCA products were cloned into the pGEM7 plasmid vector using the unique restriction sites, identified as HindIII for DNA-A, and as EcoRI for DNA-B, respectively. Ten DNA-A clones and two DNA-B component clones were sequenced. The DNA-A components ranged in size from 2,751 (KM066100) to 2,752 bp (KJ939448), whereas the DNA-B components were 2,757 bp in size (KJ939447). Analysis of the viral sequences from the DNA-A clones indicated they had the characteristics of a typical genome of a begomovirus DNA-A component that consist of a hairpin stem-loop structure in the intergenic region, two tandem copies of the iteron (TGGAGAC) located between the nt coordinates 2675 and 2680, 2682 and 2688 predicted to be involved in Rep binding, and six predicted genes encoding proteins with high sequence identity to those encoded by other WmCSV isolates. The 10 DNA-A component sequences were aligned with sequences for previously described WmCSV isolates available in GenBank using Muscle, followed by pairwise comparisons using SDT software (4). The analysis revealed that the cloned DNA-A components shared 99 to 100% nt sequence identity with each other, and 97 to 98% nt identity with WmCSV isolates reported from Yemen (AJ012081), Jordan (EU561237), Iran (AJ245652), and Sudan (AJ245650). Further, the WmCSV DNA-B from Saudi Arabia shared the highest nt identity with sequences from Yemen (AJ012082) at 96%, Iran (AJ245653) at 95%, and only 94% with DNA-B from both Sudan (AJ245651) and Jordan (EU561236). To our knowledge, this is the first report of WmCSV in Saudi Arabia. WmCSV poses a serious threat to the production of this highly valued crop in Saudi Arabia and considerably reduces crop yield (1). References: (1) I. D. Bedford et al. Eur. J. Plant Pathol. 100:243, 1994. (2) A. Idris et al. Plant Dis. 97:910, 2007. (3) A. Kheyr-Pour et al. Phytopathology 90:629, 2000. (4) B. Muhire et al. Arch. Virol. 158:1411, 2013.
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Paramitha, Ni Kadek Diah Ayu, Putu Timur Ina, and I. Desak Putu Kartika Pratiwi. "KARAKTERISTIK BISKUIT DENGAN PEMANFAATAN UMBI DAN PASTA DAUN SINGKONG (Manihot esculenta Cranz)." Jurnal Ilmu dan Teknologi Pangan (ITEPA) 7, no. 3 (October 1, 2018): 140. http://dx.doi.org/10.24843/itepa.2018.v07.i03.p08.
Full textAbstract:
The purposes of this research were to know the effect comparation of cassava flour and cassava leaves paste on the characteristics of biscuit and to know the right comparation from cassava flour and cassava leaves paste to produce biscuit the best characteristics. The experimental design was used randomized block design with the treatment comparation of cassava flour and cassava leaves paste that 95% : 5%, 92% : 8%, 89% : 11%, 86% : 14%, 83% : 17%; and 80% : 20%. The treatment was repeated as many as 3 times so that 18 experimental units were obtained. The data was analyzed with ANOVA and if the influential on variable observed continued with the Duncan test. The results showed that the comparation of cassava flour and cassava leaves paste significantly affected to water content, ash content, crude fiber content, chlorofil total, beta karoten total, and hedonic test (colour, aroma, texture, taste, and overall acceptance) and scoring test (texture). Comparation from cassava flour and cassava leaves paste (92% : 8%) is the best characteristics with water content is 2,77%, ash content was 2,58%, crude fiber content is 15,39%, chlorofil total is 22,93%, beta karoten total is 434,96% , color liked, flavor of cassava leaves liked, texture very crispy and liked, taste liked, and overall acceptance liked.
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Barbosa, J. C., A. P. M. Teixeira, A. G. Moreira, L. E. A. Camargo, A. Bergamin Filho, E. W. Kitajima, and J. A. M. Rezende. "First Report of Tomato chlorosis virus Infecting Tomato Crops in Brazil." Plant Disease 92, no. 12 (December 2008): 1709. http://dx.doi.org/10.1094/pdis-92-12-1709c.
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During 2006 and 2007 in the region of Sumaré, state of São Paulo, Brazil, surveys were done on tomato (Solanum lycopersicum L.) virus diseases in three open field-grown crops. The data revealed low incidence (0.25 to 3.42%) of randomly distributed plants exhibiting interveinal chlorosis and some necrosis on the basal leaves. Symptoms were only observed on old fruit-bearing plants. Preliminary analysis of thin sections of symptomatic leaves from one plant by transmission electron microscopy revealed the presence of aggregates of thin, flexible, and elongated particles in some phloem vessels, suggesting infection with a member of the genus Crinivirus, family Closteroviridae. Total RNA was extracted separately from leaves of 10 symptomatic plants and used for one-step reverse transcription (RT)-PCR using the HS-11/HS-12 primer pair, which amplifies a fragment of 587 bp from the highly conserved region of the heat shock protein (HSP-70) homolog gene reported for Tomato infectious chlorosis virus (TICV) and Tomato chlorosis virus (ToCV) (1). The RT-PCR product was subsequently tested by nested-PCR for single detection of TICV and ToCV using primer pairs TIC-3/TIC-4 and ToC-5/ToC-6, respectively (1). Only one fragment of approximately 463 bp was amplified from 7 of the 10 plants with the primer pair specific for ToCV. No amplification was obtained with the primers specific for TICV. Two amplicons of 463 bp were purified and directly sequenced in both directions. Sequence comparisons of the 463-bp consensus sequence (GenBank Accession No. EU868927) revealed 99% identity with the reported sequence of ToCV from the United States (GenBank Accession No. AY903448) (3). Virus-free adults of Bemisia tabaci biotype B confined on symptomatic tomato leaves for a 24-h acquisition access period were able to transmit the virus to healthy tomato plants, which reproduced the original symptoms on the bottom leaves 65 days after inoculation under greenhouse conditions. Infection from transmission was confirmed by RT-PCR using the HS-11/HS-12 primer pair. In addition to B. tabaci biotype B, the greenhouse whitefly, Trialeurodes vaporariorum, has also been reported as a vector of ToCV, although it is less efficient than the B. tabaci biotype B in transmission of this virus (4). T. vaporariorum, which was previously considered limited to greenhouses, was recently reported in tomato and green bean (Phaseolus vulgaris L.) crops under field conditions in São Paulo State (2). Therefore, it might also contribute to the spread of ToCV in tomato crops in São Paulo. To our knowledge, this is the first report of ToCV in Brazil and South America. References: (1) C. I. Dovas et al. Plant Dis.86:1345, 2002. (2) A. L. Lourenção et al. Neotrop. Entomol. 37:89, 2008. (3) W. M. Wintermantel et al. Arch. Virol. 15:2287, 2005. (4) W. M. Wintermantel and G. C. Wisler. Plant Dis. 90:814, 2006.
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Shahid, Muhammad Shafiq. "Watermelon Chlorotic Stunt Virus is Associated with Cucumber Yellow Mosaic Symptoms in Oman." International Journal of Agriculture and Biology 25, no. 04 (April 1, 2021): 859–62. http://dx.doi.org/10.17957/ijab/15.1739.
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Cucumber (Cucumis sativus; family Cucurbitaceae) plants exhibiting begomovirus-like symptoms such as yellowing, mosaics and stunting were studied using cloning, sequencing, Species Demarcation Tool followed by phylogenetic clustering. The complete genome of DNA-A showed maximum sequence identity of 98.7% with the corresponding DNA-A of an isolate from “Iran” strain of Watermelon chlorotic stunt virus (WmCSV). The DNA-B displayed 97.5% nt identity with the component of DNA-B of WmCSV from Iran, too. Our results confirmed that yellowing and mosaic symptoms of cucumber are associated with a bipartite begomovirus (WmCSV). This study is the first characterization of WmCSV in association with described symptoms in cucumber from Oman. © 2021 Friends Science Publishers
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Keinath, Anthony P., Kai-Shu Ling, Scott Adkins, Daniel K. Hasegawa, Alvin M. Simmons, Steve Hoak, H. Charles Mellinger, and Chandrasekar S. Kousik. "First Report of Cucurbit Leaf Crumple Virus Infecting Three Cucurbit Crops in South Carolina." Plant Health Progress 19, no. 4 (January 1, 2018): 322–23. http://dx.doi.org/10.1094/php-07-18-0039-br.
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Virus-like symptoms of curled and crumpled leaves, bright yellow chlorosis, and marginal leaf necrosis typical of begomovirus infection were observed on watermelon, summer squash, and muskmelon in three counties in South Carolina in August 2017. Genus-specific primers for begomovirus-A and begomovirus-B components produced amplicons of the expected sizes. Sanger sequencing of amplicons from both A and B components and BLASTn analysis revealed a high nucleotide sequence identity in seven watermelon samples from Beaufort and Charleston counties and five muskmelon samples from Charleston County with cucurbit leaf crumple virus.
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Shakeel, Muhammad Taimoor. "Transmission of Cucurbit Chlorotic Yellows Virus (CCYV) by Whitefly Biotype B in Riyadh, Saudi Arabia." International Journal of Agriculture and Biology 20, no. 02 (February 1, 2018): 241–48. http://dx.doi.org/10.17957/ijab/15.0483.
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O'Connell, Kevin P., and Jo Handelsman. "Foliar Chlorosis in Symbiotic Host and Nonhost Plants Induced by Rhizobium tropici Type B Strains." Applied and Environmental Microbiology 59, no. 7 (1993): 2184–89. http://dx.doi.org/10.1128/aem.59.7.2184-2189.1993.
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Pak, Chun-Ho, and Chiwon W. Lee. "MICRONUTRIENT TOXICITY IN PETUNIA HYBRIDA." HortScience 27, no. 6 (June 1992): 687e—687. http://dx.doi.org/10.21273/hortsci.27.6.687e.
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Foliar micronutrient toxicity symptoms of Petunia hybrida `Ultra Crimson Star' were induced by elevated levels (from 0.25 to 6 mM) of boron (B), copper (Cu), iron (Fe), manganese (Mn), molybdenum (Mo) and zinc (Zn) in the nutrient solution. Foliar toxicity symptoms of most micronutrients (except Fe) were characterized by leaf yellowing, interveinal chlorosis, and marginal necrosis. Mo toxicity was most severe. Leaf abnormality was not induced by Fe in the concentration range tested. Visible foliar toxicity symptoms developed when nutrient solution contained 5.4, 32, 28, 24, and 16 mg· liter-1, respectively, of B, Cu, Mn, Mo and Zn. Biomass yield was reduced when the fertilizer solution contained (in mg· liter-1): 22 B, 64 Cu, 335 Fe, 28 Mn, 24 Mo, and 33 Zn.
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Yoon, Beyounghan, and Harvey J. Lang. "Effect of Irradiance Level and Paclobutrazol on Reducation of Leaf Damage in Begonia × cheimantha." HortScience 33, no. 3 (June 1998): 446d—446. http://dx.doi.org/10.21273/hortsci.33.3.446d.
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Begonia × cheimantha (Christmas or Lorraine begonia) is a popular holiday crop in Europe, with certain cultivars having outstanding postharvest characteristics. Its commercial production in the southern United States has been limited by the occurrence of mottled leaf chlorosis and necrosis, apparently due to environmental stress. In this study, B. × cheimantha `Emma' was grown in the fall in a glass greenhouse at College Station, Texas, under either 0%, 60%, or 87% polyethylene shade cloth. Leaf chlorosis and necrosis was very severe on plants grown in full sun (≈650 mol·m–2·s–1), with slight chlorosis on plants under 60% shade. Plants under full sun, however, were more compact, flowered earlier, and had shorter peduncles with more flowers than those grown under shade. Reducing the vegetative long-day treatment period from 7 to 4 weeks had no effect on leaf damage development. Plants treated with paclobutrazol were shorter and had less leaf damage than untreated plants. Leaves of treated plants had a relatively higher concentration of soluble protein, chlorophyll, and enhanced activities of ascorbate peroxidase (AsA), dehydroascorbate (DHA) reductase, and monodehydro-ascorbate (MDHA) reductase than untreated plants. For Texas growing conditions, these preliminary studies indicate that B. × cheimantha should be grown under reduced light intensities, with excessive height and leaf damage being controlled with growth retardants such as paclobutrazol.
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Coutts, Brenda A., John A. Walsh, and Roger A. C. Jones. "Evaluation of resistance to Turnip mosaic virus in Australian Brassica napus genotypes." Australian Journal of Agricultural Research 58, no. 1 (2007): 67. http://dx.doi.org/10.1071/ar06096.
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Forty-three Australian cultivars or breeding lines of Brassica napus (canola, oilseed rape) and 2 cultivars of Brassica juncea (mustard) were inoculated with infective sap containing isolate WA-Ap of Turnip mosaic virus (TuMV), which belongs to TuMV pathotype 8. The types of reactions obtained were: necrotic spots in inoculated leaves without systemic infection (RN), chlorotic blotches in inoculated leaves without systemic infection (R), and chlorotic blotches in inoculated leaves accompanied by systemic infection that consisted of either necrotic spots (+N) or chlorotic blotches (+). The RN and +N reactions are consistent with those expected in the presence of 4 strain-specific TuMV resistance genes TuRB01 (+N response), TuRB03 (+N response) and TuRB04 with TuRB05 (RN), with + indicating a susceptible response. However, which resistance gene corresponds to the R response is unclear. The RN (TuRB04 with TuRB05) type of response was the commonest. Only one genotype lacked any TuMV resistance, and segregation for more than one different type of resistance response occurred within 22 genotypes and some segregated for resistance and susceptibility. Some genotypes segregated for all 3 types of resistance response found. The reaction of 2 plants of cv. Rivette was atypical as they developed both necrotic spots in inoculated leaves and systemic chlorotic spots. Since breeding for TuMV resistance is not undertaken in Australia, these results indicate frequent but inadvertent crossing with parental lines carrying TuMV resistance. Widespread occurrence of TuMV resistance genes and the possibility that many Australian TuMV isolates may not be well adapted to B. napus may explain the low incidence of this virus found in Australian B. napus crops.
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Freitas, D. M. S., I. Nardin, N. Shimoyama, J. A. C. Souza-Dias, and J. A. M. Rezende. "First Report of Tomato chlorosis virus in Potato in Brazil." Plant Disease 96, no. 4 (April 2012): 593. http://dx.doi.org/10.1094/pdis-12-11-1068-pdn.
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Potato plants (Solanum tuberosum cv. Ágata) exhibiting symptoms of leaf roll and interveinal chlorosis, especially on older leaves, were found in a commercial crop in the County of Cristalina, State of Goiás, Brazil in June 2011. The crop was severely infested by whitefly Bemisia tabaci biotype B. Four potato tubers from symptomatic plants were indexed for the presence of the following viruses: Tomato chlorosis virus (ToCV), Potato leaf roll virus (PLRV), Tomato severe rugose virus (ToSRV), and Potato virus Y (PVY). Total RNA was extracted separately from each tuber and used for reverse transcription (RT)-PCR using the HS-11/HS-12 primer pair, which amplifies a fragment of 587 bp from the highly conserved region of the heat shock protein (HSP-70) homolog gene reported for ToCV. The RT-PCR product was subsequently tested by nested-PCR for detection of ToCV with specific primers ToC-5/ToC-6 (2). Amplicons of 463 bp, amplified from total RNA separately extracted from three tubers, were purified and directly sequenced. Comparisons among the three consensus sequences of 448 bp (GenBank Accession Nos. JQ288896, JQ288897, and JQ288898) revealed respectively, 98, 100, and 100% identity with the reported sequence of a tomato isolate of ToCV from Brazil (GenBank Accession No. EU868927) (1). For ToSRV detection, total DNA was extracted from two tubers and a fragment of approximately 820 bp was amplified by PCR with specific primers (3). PLRV and PVY were indexed in two and three tubers, respectively, by double-antibody sandwich-ELISA (SASA, Edinburg, Scotland). Virus-free B. tabaci biotype B were separately transferred to potato and tomato leaves infected with ToCV for an acquisition access period of 24 h. Groups of 30 viruliferous whitefly were transferred to four, young, sprout-grown potato plants cv. Ágata (two plants per virus isolate) for 24-h inoculation access period. After 37 days of inoculation, one plant inoculated with the potato and tomato isolates of ToCV, respectively exhibited symptoms of leaf roll and interveinal chlorosis on order leaves, which were similar to that induced by PLRV. Experimental infection of potato plants with ToCV, which induced leaf roll symptoms resembling PLRV infection, was reported in the United States by Wisler et al. (4). The potato isolate of ToCV was also transmitted by B. tabaci to one of two inoculated tomato plants. The presence of ToCV in all inoculated plants was detected by nested-RT-PCR as described above. To our knowledge, this is the first report on detection of ToCV in field potato plants in the world. Considering that ToCV occurs in innumerous countries around the world, it is transmitted by a cosmopolitan insect, and it induces symptoms similar to PLRV, this finding triggers an alert to field dependent seed-potato multiplication, virus inspector, and certification system. References: (1) J. C. Barbosa et al. Plant Dis. 92:1709, 2008. (2) C. I. Dovas et al. Plant Dis. 86:1345, 2002. (3) F. R. Fernandes et al. Trop. Plant Pathol. 35:43, 2010. (4) G. C. Wisler et al. Plant Dis. 82:270, 1998.
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Pratt, R. G. "Occurrence and Virulence of Bipolaris hawaiiensis on Bermudagrass (Cynodon dactylon) on Poultry Waste Application Sites in Mississippi." Plant Disease 85, no. 11 (November 2001): 1206. http://dx.doi.org/10.1094/pdis.2001.85.11.1206b.
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Bipolaris hawaiiensis has been reported on bermudagrass (Cynodon dactylon) and other Cynodon spp. from subtropical areas around the world (2). This pathogen has not previously been reported on bermudagrass in North America (1) nor has its virulence been compared with that of other Bipolaris spp. on this host. In July and October 1999, frequencies of dematiaceous hyphomycetous pathogens in live but symptomatic leaves of bermudagrass were determined on two poultry waste application sites in Smith and Covington counties, MS, where foliar disease symptoms were widespread. Common bermudagrass was being grazed in Covington County, and cv. Alicia was being grown for hay in Smith County. At each date and site, 100 stems with leaves exhibiting symptoms of chlorosis and necrosis were collected, and a single leaf with well-developed symptoms from each stem was assayed for pathogens by surface-disinfesting, plating on water agar, and observing fungal sporulation. Multiple species of pathogens were detected on most leaves. Identities and mean frequencies of observed pathogen species across both sites and sampling dates were Exserohilum rostratum (62%), Bipolaris cynodontis (98%), Curvularia lunata (28%), C. geniculata (20%), B. spicifera (3%), and B. hawaiiensis (3%). B. hawaiiensis was detected at both sites and on both sampling dates. It was distinguished from B. cynodontis by smaller conidia (14 to 28 μm long) and from B. spicifera by more than three pseudosepta per conidium. Virulence of B. hawaiiensis on bermudagrass, compared with B. cynodontis and B. spicifera, was assessed in two identical inoculation experiments using three pathogen-inoculated treatments plus an uninoculated control. In each experiment, foliage of 12-week-old plants in five replicate pots per treatment was sprayed with 4 × 104 conidia per ml of water of each pathogen. The pots were incubated under 12-h plant-growth lights at 25°C for 3 days in a water-saturated atmosphere to initiate infection and then grown for seven additional days in ambient air under plant-growth lights at 25°C. All three pathogens induced symptoms of chlorosis and necrotic lesions. Symptoms induced by B. hawaiiensis were similar in severity to those produced by B. spicifera and less severe than those produced by B. cynodontis. To our knowledge, this is the first report of B. hawaiiensis on bermudagrass in North America. The site in Smith County also apparently represents its northernmost known point of occurrence on this continent (2). References: (1) D. F. Farr et al. Fungi on Plants and Plant Products in the United States. The American Phytopathological Society, St. Paul, MN, 1989. (2) A. Sivanesan. Graminicolous Species of Bipolaris, Curvularia, Drechslera, Exserohilum and their Teleomorphs. Mycol. Pap. No. 158, CAB International Mycological Institute, Wallingford, U.K., 1987.
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Krug, Brian A., Brian E. Whipker, Jonathan Frantz, and Ingram McCall. "Characterization of Calcium and Boron Deficiency and the Effects of Temporal Disruption of Calcium and Boron Supply on Pansy, Petunia, and Gerbera Plugs." HortScience 44, no. 6 (October 2009): 1566–72. http://dx.doi.org/10.21273/hortsci.44.6.1566.
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Pansy (Viola ×wittrockiana Gams.), petunia (Petunia ×hybrida hort. Vilm.), and gerbera daisy (Gerbera jamesonii Bol. ex Adlam.) plants were grown hydroponically to characterize the deficiency symptoms caused by the absence of calcium (Ca) or boron (B). Primary symptoms occurred on the youngest tissue for both elements, but distinct differences between Ca and B deficiencies were observed. Plants responding to Ca deficiency exhibited discoloration and upward rolling of leaves and ultimately necrosis. Plants responding to B deficiency exhibited minor chlorosis, upward curling, and thickening of leaves, distorted meristems, and strap-like leaves. A second experiment investigated how a temporary disruption of Ca or B affects the plant throughout the crop cycle. Either Ca or B was removed from the nutrient solution for a 7-day period from Day 15 to Day 21, Day 22 to Day 28, or Day 29 to Day 35 after sowing. After the 7-day disruption, the respective element was reintroduced to the plants. Regardless of when the plants were deprived of Ca or B, the symptoms of the respective deficiency were present at the end of the experiment. These studies have shown that a temporary disruption of either Ca or B can cause lasting symptoms throughout the plug production cycle. Also, the symptoms that have been observed in plug production were most similar to those symptoms caused by B deficiency, not Ca deficiency.
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Smith, Thomas J., Elaine Chase, Timothy Schmidt, and Keith L. Perry. "The Structure of Cucumber Mosaic Virus and Comparison to Cowpea Chlorotic Mottle Virus." Journal of Virology 74, no. 16 (August 15, 2000): 7578–86. http://dx.doi.org/10.1128/jvi.74.16.7578-7586.2000.
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ABSTRACT The structure of cucumber mosaic virus (CMV; strain Fny) has been determined to a 3.2-Å resolution using X-ray crystallography. Despite the fact that CMV has only 19% capsid protein sequence identity (34% similarity) to cowpea chlorotic mottle virus (CCMV), the core structures of these two members of the Bromoviridaefamily are highly homologous. As suggested by a previous low-resolution structural study, the 305-Å diameter (maximum) of CMV is ∼12 Å larger than that of CCMV. In CCMV, the structures of the A, B, and C subunits are nearly identical except in their N termini. In contrast, the structures of two loops in subunit A of CMV differ from those in B and C. These loops are 6 and 7 residues longer than the analogous regions in CCMV. Unlike that of CCMV, the capsid of CMV does not undergo swelling at pH 7.0 and is stable at pH 9.0. This may be partly due to the fact that the N termini of the B and C subunits form a unique bundle of six amphipathic helices oriented down into the virion core at the threefold axes. In addition, while CCMV has a cluster of aspartic acid residues at the quasi-threefold axis that are proposed to bind metal in a pH-dependent manner, this cluster is replaced by complementing acids and bases in CMV. Finally, this structure clearly demonstrates that the residues important for aphid transmission lie at the outermost portion of the βH-βI loop and yields details of the portions of the virus that are hypothesized to mediate binding to aphid mouthparts.
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Yermiyahu, Uri, Alon Ben-Gal, and Pinchas Sarig. "Boron Toxicity in Grapevine." HortScience 41, no. 7 (December 2006): 1698–703. http://dx.doi.org/10.21273/hortsci.41.7.1698.
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Table grape production has recently become popular in arid and semiarid regions where conditions of salinity and excess boron (B) can be prevalent. This study addresses B toxicity in grapevine to define toxicity symptoms and evaluate growth, production, and B accumulation. The effect of excess B on grapevines (Vitis vinifera L. cv. Sugraone) was evaluated in a 4-year study in Israel's Jordan Valley. Vines were grown in 60-L perlite-filled containers and irrigated with complete nutrient solutions with four B concentrations: 0.03, 0.12, 0.21, and 0.31 mm. Vines were monitored for growth, yield, and B accumulation. Boron accumulation in leaves correlated with B toxicity symptoms that materialized as chlorosis and necrosis of leaves beginning at their margins, reduced leaf size, and reduced internodal distance between adjacent leaves. Boron accumulated in grapevine leaves linearly as a function of increased B in irrigation solution with time and with age of leaves. The highest B levels were found at the end of each season and in the oldest leaves. No long-term (multiyear) effect of exposure to B was observed because similar accumulation patterns and levels were found in each year of the experiment. Hence, consistently sampled diagnostic leaves and time of sampling for B analysis is seen to be critical to provide valid comparisons between vines or over time. Boron supply influenced vine growth. At low levels of B (0.03 mm), canopy development was restricted but trunk size was not. At high levels of B (0.21 and 0.31 mm), substantial visual symptoms of B toxicity were observed, and the rate of trunk growth was reduced, but pruning biomass was not influenced. Despite severe visual toxicity damage and reduced overall growth rates, commercial fruit yield of the vines remained unaffected by high environmental B levels.
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Ribeiro, Simone G., Darren P. Martin, Cristiano Lacorte, Isabella C. Simões, Deborah R. S. Orlandini, and Alice K. Inoue-Nagata. "Molecular and Biological Characterization of Tomato chlorotic mottle virus Suggests that Recombination Underlies the Evolution and Diversity of Brazilian Tomato Begomoviruses." Phytopathology® 97, no. 6 (June 2007): 702–11. http://dx.doi.org/10.1094/phyto-97-6-0702.
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Tomato chlorotic mottle virus (ToCMoV) is an emerging begomovirus species widely distributed throughout tomato-growing regions of Brazil. ToCMoV appears to have expanded its geographic range recently, invading tomato-growing areas that were free of begomovirus infection before 2004. We have determined the first complete genome sequence of an infectious ToCMoV genome (isolate BA-Se1), which is the first begomovirus species isolated in the northeast of Brazil. When introduced by particle bombardment into tomato, the cloned ToCMoV-[BA-Se1] DNA-A and DNA-B components caused typical chlorotic mottle symptoms. The cloned virus was whitefly-transmissible and, although it was infectious in hosts such as Nicotiana benthamiana, pepper, tobacco, and Nicandra physaloides, it was unable to infect Arabidopsis thaliana, bean, N. glutinosa, and Datura metel. Sequence and biological analyses indicate that ToCMoV-[BA-Se1] is a typical New World begomovirus sp. requiring both DNA-A and DNA-B components to establish systemic infections. Although evidence of multiple recombination events was detected within the ToCMoV-[BA-Se1] DNA-A, they apparently occurred relatively long ago, implying that recombination probably has not contributed to the recent emergence of this species.
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MAJCHRZAK, LESZEK, and GRZEGORZ SKRZYPCZAK. "Wpływ systemu uprawy roli oraz międzyplonu ścierniskowego na właściwości fizyczne gleby i plonowanie pszenicy jarej." Agronomy Science 65, no. 2 (June 21, 2010): 1–9. http://dx.doi.org/10.24326/as.2010.2.1.
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Badania przeprowadzono w latach 2007–2008 w Zakładzie Doświadczalno- -Dydaktycznym Brody należącym do Uniwersytetu Przyrodniczego w Poznaniu. Ich celem było poznanie wpływu tradycyjnej uprawy roli i siewu bezpośredniego zarówno pod gorczycę białą uprawianą jako międzyplon ścierniskowy (A), jak i pod zasiewy pszenicy jarej (B) na plonowanie i elementy struktury plonu pszenicy jarej, zmiany fizycznych właściwości gleby oraz określenie wartości SPAD (względnej zawartości chlorofilu). Przeprowadzone badania wykazały, że tradycyjna uprawa roli, czyli podorywka pod gorczycę i orka siewna pod pszenicę jarą istotnie zwiększyły liczbę źdźbeł kłosonośnych na jednostce powierzchni w porównaniu z obiektami, na których oba gatunki roślin uprawiano w systemie siewu bezpośredniego, co z kolei sprzyjało istotnemu zwiększeniu zwięzłości gleby na poziomie 0-10 cm i 20–30 cm. Większą zawartością chlorofilu w liściach wyrażoną w jednostkach SPAD charakteryzowała się pszenica uprawiana systemem płużnym. Zarówno plon, jak i masa hektolitra ziarna pszenicy były większe przy jej uprawie w technologii płużnej. Istotność różnic pomiędzy systemami uprawy nie została jednak potwierdzona statystycznie.
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You, J. M., Q. H. Wang, X. M. Lin, J. Guo, L. Q. Ai, M. D. Zhang, S. Mu, et al. "First Report of Gray Mold of Rhizoma paridis Caused by Botrytis cinerea in China." Plant Disease 98, no. 10 (October 2014): 1434. http://dx.doi.org/10.1094/pdis-03-14-0336-pdn.
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Rhizoma paridis is a perennial, traditional Chinese medicinal herb. In May 2013, a disease was observed in an approximately 10 ha cultivated field in Enshi, Hubei Province, China. Approximately 80% of plants in the field were affected. Symptoms were visible on the basal leaves of affected plants. Chlorosis followed by necrosis started at the leaf tips and margins and gradually spread inward until the entire leaf was necrotic. Thick, gray mycelium and conidia were visible on both sides surface of leaves under wet, humid conditions. The leading edge of the chlorotic leaves was excised from 20 plant samples surface disinfested with 1% NaOCl solution for 1 min, rinsed in sterile water, air dried, and placed on potato dextrose agar (PDA). Plates were incubated at 22°C in the dark. Mycelia were initially hyaline and white, and became dark gray after 72 h. Mycelia were septate with dark branched conidiophores. Conidia were smooth, hyaline, ovoid, aseptate, and ranged from 8 to 14.5 × 7 to 8.5 μm. Numerous hard, small, irregular, and black sclerotia that were 1 to 3 × 2 to 5 mm were visible on PDA plates after 12 days. The fungus was identified as Botrytis cinerea on the basis of these characters (1). The internal transcribed spacer (ITS) region of rDNA was amplified using the ITS1 and ITS4 primer and sequenced (GenBank Accession No. KF265499). BLAST analysis of the PCR product showed 99% identity to Botryotinia fuckeliana (perfect stage of B. cinerea) (EF207415.1, EF207414.1). The pathogen was further identified to the species level as B. cinerea using gene sequences from glyceraldehyde-3-phosphate dehydrogenase (G3PDH), heat-shock protein 60 (HSP60), and DNA-dependent RNA polymerase subunit II (RPB2) (2) (KJ638600, KJ638602, and KJ638601). Pathogenicity was tested by spraying the foliage of 40 two-year-old plants with a suspension of 106 conidia per ml of sterile distilled water. Each plant received 30 ml of the inoculum. Ten healthy potted plants were inoculated with sterilized water as control. All plants were covered with plastic bags for 5 days after inoculation to maintain high relative humidity and were placed in a growth chamber at 22°C. The first foliar lesions developed on leaves 7 days after inoculation and were similar to those observed in the field. No symptoms developed on the control plants. B. cinerea was consistently re-isolated from all artificially inoculated plants. The pathogenicity test was completed twice. To our knowledge, this is the first report of gray mold of R. paridis caused by B. cinerea in China. The root of R. paridis is the most commonly used Chinese herbal medicine to treat viper bites. In recent years, cultivation of this herb has increased in China because of its high value. Consequently, the economic importance of this disease is likely to increase with the greater prevalence of this host species. References: (1) H. L. Barnett and B. B. Hunter. Illustrated Genera of Imperfect Fungi. Burgess Publishing Company, Minneapolis, MN, 1972. (2) M. Staats et al. Mol. Biol. Evol. 22:333, 2005.
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Sotiropoulos, T. E., I. N. Therios, and K. N. Dimassi. "Seasonal accumulation and distribution of nutrient elements in fruit of kiwifruit vines affected by boron toxicity." Australian Journal of Experimental Agriculture 46, no. 12 (2006): 1639. http://dx.doi.org/10.1071/ea05081.
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The objectives of the present research were to study the effect of boron (B) toxicity on the seasonal accumulation of nutrient elements in fruit of kiwifruit vines and also to study the distribution of nutrient elements within a mature fruit. The kiwifruit vines were 12 years old and grown on soil developed on alluvial deposits. One part of the experimental orchard was irrigated from a well with good quality water (0.3 mg B/L) and served as a control, whereas the other part was irrigated with high B water (3.2 mg B/L) pumped by another well. Symptoms of B toxicity in leaves were clearly visible in the form of chlorosis. At the end of June 1998, necrotic spots were apparent in the leaf blade. The seasonal patterns for the various macro- and micronutrient elements could be broadly grouped into 2 types: (i) the P, Ca and Fe contents in fruit of both orchards declined gradually until they reached values which remained relatively constant until harvest; (ii) the N, K, Mg, Mn and Zn contents in fruit tended to decline steadily throughout the sampling period. Irrigation of kiwifruit vines with high B water did not significantly affect fruit N, P, K, Mg, Mn and Fe contents, whereas it decreased Ca contents and increased Zn and B contents. The decrease in B content from the basal part of the fruit towards the apical could be ascribed to the low mobility of B within the plant. The distribution pattern of B in fruit is not uniform; this indicates that during interpretation, fruit analysis data should be treated with caution, as the analysis of an entire fruit represents an average of widely different B contents. The higher B content in the basal part of flesh suggests that this tissue is the most sensitive indicator of B toxicity in fruit.
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Lee, Taeklim, Kyung-Do Kim, Ji-Min Kim, Ilseob Shin, Jinho Heo, Jiyeong Jung, Juseok Lee, Jung-Kyung Moon, and Sungteag Kang. "Genome-Wide Association Study for Ultraviolet-B Resistance in Soybean (Glycine max L.)." Plants 10, no. 7 (June 29, 2021): 1335. http://dx.doi.org/10.3390/plants10071335.
Full textAbstract:
The depletion of the stratospheric ozone layer is a major environmental issue and has increased the dosage of ultraviolet-B (UV-B) radiation reaching the Earth’s surface. Organisms are negatively affected by enhanced UV-B radiation, and especially in crop plants this may lead to severe yield losses. Soybean (Glycine max L.), a major legume crop, is sensitive to UV-B radiation, and therefore, it is required to breed the UV-B-resistant soybean cultivar. In this study, 688 soybean germplasms were phenotyped for two categories, Damage of Leaf Chlorosis (DLC) and Damage of Leaf Shape (DLS), after supplementary UV-B irradiation for 14 days. About 5% of the germplasms showed strong UV-B resistance, and GCS731 was the most resistant genotype. Their phenotypic distributions showed similar patterns to the normal, suggesting UV-B resistance as a quantitative trait governed by polygenes. A total of 688 soybean germplasms were genotyped using the Axiom® Soya 180K SNP array, and a genome-wide association study (GWAS) was conducted to identify SNPs significantly associated with the two traits, DLC and DLS. Five peaks on chromosomes 2, 6, 10, and 11 were significantly associated with either DLC or DLS, and the five adjacent genes were selected as candidate genes responsible for UV-B resistance. Among those candidate genes, Glyma.02g017500 and Glyma.06g103200 encode cryptochrome (CRY) and cryptochrome 1 (CRY1), respectively, and are known to play a role in DNA repair during photoreactivation. Real-time quantitative RT-PCR (qRT-PCR) results revealed that CRY1 was expressed significantly higher in the UV-B-resistant soybean compared to the susceptible soybean after 6 h of UV-B irradiation. This study is the first GWAS report on UV-B resistance in soybean, and the results will provide valuable information for breeding UV-B-resistant soybeans in preparation for climate change.
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Picchioni, G. A., S. Miyamoto, and J. B. Storey. "Boron Uptake and Effects on Growth and Carbohydrate Partitioning of Pistachio Seedlings." Journal of the American Society for Horticultural Science 116, no. 4 (July 1991): 706–11. http://dx.doi.org/10.21273/jashs.116.4.706.
Full textAbstract:
Seedlings of three pistachio rootstock (Pistacia atlantica Desf., P. terebinthus L., and P. integerrima Stewart × atlantica) and of the pistachio scion cultivar Kerman (P. vera. L.) were grown in calcareous sandy loam irrigated with B solutions (0 to 15 mg·liter-1) in a greenhouse. After 10.5 months of B treatment, rootstock seedling growth (root + stem weight and leaf dry weight, area, and number per plant) had decreased linearly with B application, which provided up to 48.9 mg B/liter in the soil saturation extract. Growth of P. terebinthus was greater than P. atlantica throughout the concentration range, but species sensitivity to B did not differ. Nine months of B at concentrations up to 10.7 mg·liter-1 in the saturation extract did not alter the growth of P. vera seedlings. Leaf B concentrations of all species increased linearly with saturation extract B concentration after each of two growing periods and were higher in leaves of P. terebinthus than P. atlantica. From 62% to 75% of B was present in leaf tissue of the rootstock seedlings, with lower quantities in roots and stems. Boron toxicity appeared initially as interveinal chlorosis and apical necrosis of 1-month-old, fully expanded leaflets of the rootstock species. By 4 months, symptoms in some treatments advanced to severe necrosis of leaflets. Boron addition increased the concentrations of total leaf sugars (glucose, fructose, and sucrose) and root starch, decreased root glucose concentrations, and had no effect on other root carbohydrates of P. vera seedlings. Leaf carbohydrate supply limitations and altered root carbohydrate status may be consequences of high B in P. vera seedling leaves.
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Gibson, James L., Brian E. Whipker, Dharmalingam S. Pitchay, Paul V. Nelson, and C. Ray Campbell. "645 Foliar Symptomology and Tissue Concentrations of Nutrient Deficient Ornamental Cabbage Plants." HortScience 35, no. 3 (June 2000): 508E—509. http://dx.doi.org/10.21273/hortsci.35.3.508e.
Full textAbstract:
Elemental deficiencies of N, P, K, Ca, Mg, S, Fe, Mn, Cu, Zn, and B were induced in `Osaka White' ornamental cabbage (Brassica oleracea var. acephala L.) plants. Seedlings were planted in 4.7-L plastic containers and fertilized with a complete modified Hoagland's solution or this solution minus the element that was to be investigated. Plants were harvested for tissue analysis as well as dry weight when initial foliar symptoms were expressed and later under advanced deficiency symptoms. Root architecture was also recorded for the plants treated with the solutions. The containers were replicated three times for each of the two harvests and were randomized in a complete-block design. Deficiency symptoms for all treatments were observed within five weeks. The most dramatic expression of foliar symptoms occurred with N (a purplish tinge on underside of lower foliage leading to necrotic margins on the mature leaves), P (elongated internodes and a purplish tinge on underside of mature leaves), K (compact internodes with chlorotic lower foliage leading to necrotic patches on the leaf margins and blade), Fe (bright yellow upper foliage leading to a bleach white appearance), Ca (complete meristem necrosis with lower foliage becoming chlorotic then necrotic), and B (deformed young leaves and fully expanded leaves becoming thick, leathery, and brittle). The dry weight of plants treated with solutions not containing N, P, Ca, Fe, or B was significantly lower when compared to the control. Foliar tissue concentration data will assist plant tissue analysis laboratories in establishing foliar symptom standards for grower samples.