Artículos de revistas: "Coffee anthracnose"

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Molebila, Didiana Yanuarita, Ade Rosmana y Untung Surapaty Tresnaputra. "Trichoderma asal akar kopi dari Alor: Karakterisasi morfologi dan keefektifannya menghambat Colletotrichum Penyebab Penyakit Antraknosa secara in Vitro". Jurnal Fitopatologi Indonesia 16, n.º 2 (2 de diciembre de 2020): 61–68. http://dx.doi.org/10.14692/jfi.16.2.61-68.

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Trichoderma of coffee roots from Alor: Morphological characteristic and in vitro efficacy to inhibit Colletotrichum, causing Anthracnose Trichoderma is a fungus capable of intimate associations with plant root systems including on coffee plants. This aim of study is to determine the characteristics of Trichoderma morphospecies from coffee roots of Alor origin, East Nusa Tenggara (NTT) and its ability to inhibit the growth of Colletotrichum causing anthracnose disease in-vitro. Root samples of healthy coffee plants were taken from the location of coffee plantations in Alor District, NTT. Isolation of Trichoderma fungi from coffee roots was done by incubating the sterilized coffee roots in a layer of moist filter paper in a Petri dish for seven days. Identification of Trichoderma by observing the characteristics of the colony on the medium of potato dextrose agar (PDA) and microscopic media using microcultures (slide culture). Inhibition of Trichoderma fungi against Colletotrichum was tested by multiple culture methods on PDA media. The results of root incubation in humid conditions showed that there was four morphospecies of Trichoderma fungi, each of which had different characteristic specifications. In vitro antagonism in test on PDA medium, the first three morphospecies against Colletotrichum showed that each Trichoderma could inhibit 70.2%, 65.8%, and 63.3%, respectively, five days after inoculation. This data shows that Trichoderma isolated from coffee roots from Alor has the potential to suppress the growth of anthracnose pathogens.

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Freitas, R. L., E. Maciel-Zambolim, L. Zambolim, D. T. Lelis, E. T. Caixeta, U. P. Lopes y O. L. Pereira. "Colletotrichum boninense Causing Anthracnose on Coffee Trees in Brazil". Plant Disease 97, n.º 9 (septiembre de 2013): 1255. http://dx.doi.org/10.1094/pdis-03-13-0229-pdn.

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In Brazil, dieback and necrosis of leaves and berries of coffee trees (Coffea arabica and C. canephora) are common symptoms of anthracnose disease caused by Colletotrichum gloeosporioides (Penz.) Sacc. In April 2010, these symptoms were observed in 100% of the plants from different coffee plantations in the Brazilian states of Espírito Santo and Bahia. Ten isolates were obtained from symptomatic leaves and berries from these areas. Of the 10 isolates, one had distinct conidial morphology with hyaline and ellipsoid conidia measuring 10 to 16 × 5.0 to 7.5 μm and melanized irregular or spatulated-shaped appressoria measuring 7.5 to 11.0 × 5.5 to 8.5 μm, formed either solitary or concatenated, which concurred with the conidia description of Colletotrichum boninense. In order to confirm the identity of this isolate, the internal transcribed spacer (ITS) rRNA region and the glyceraldehyde 3-phosphate dehydrogenase (GAPDH) gene were sequenced (GenBank Accession Nos. JF683320 and JF331654, respectively) and compared to sequences from a database of C. boninense, confirming that the isolate was definitely C. boninense sensu lato, since it was exactly identical to other sequences in a large clade of isolates. To verify the pathogenicity of C. boninense in coffee and to compare the symptoms with those caused by C. gloeosporioides, leaves and berries were inoculated with the isolate of C. boninense and one representative isolate of C. gloeosporioides, both expressing the GFP (green fluorescent protein) gene. The isolates were grown for 7 days on potato dextrose agar and a conidial suspension (106 conidia × ml–1) was used to inoculate the organs, wounded and non-wounded, at different stages of development. In non-wounded organs, the conidial suspension was inoculated on the surface, and in leaves and berries used as control, the suspensions were substituted for sterile water. Leaves and berries were wounded with a sterilized needle and inoculated with 20 and 10 μl of the conidial suspension, respectively. Inoculated materials were incubated at 25°C and 100% relative humidity. The experiment was performed twice and evaluated daily for a week. No symptoms were observed on the control and non-wounded organs, while wounded organs exhibited typical anthracnose symptoms for both species. In berries, C. gloeosporioides consistently caused more severe symptoms at a faster rate than C. boninense. Both fungi caused necrosis in young but not old leaves. Typical acervuli were observed on the lesions and the fungus was successfully recovered from the inoculated tissues, which was confirmed by fluorescence microscopy, fulfilling Koch's Postulates. C. boninense has been identified as a pathogen causing anthracnose in a range of hosts worldwide. However, in Brazil, it has only been reported in pepper (Capsicum annuum) (3), passion fruit (Passiflora) (4), Hippeastrum (1) and in the medicinal plant Maytenus ilicifolia (2). To our knowledge, this is the first report of C. boninense associated with anthracnose of coffee trees in Brazil. Since the symptoms are similar to those caused by C. gloeosporioides, it can be stated that both species are associated with this disease in commercial coffee plantations in Brazil. Therefore, control strategies should consider the occurrence of C. boninense. References: (1) D. F. Farr et al. Mycol. Res. 110:1395, 2006. (2) S. A. Pileggi et al. Can. J. Microbiol. 55:1076, 2009. (3) H. J. Tozze et al. Plant Dis. 93:106, 2009. (4) H. J. Tozze et al. Australas. Plant Dis. Notes 5:70, 2010.

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Meng, Yanan, Mark L. Gleason, Rong Zhang y Guangyu Sun. "Genome Sequence Resource of the Wide-Host-Range Anthracnose Pathogen Colletotrichum siamense". Molecular Plant-Microbe Interactions® 32, n.º 8 (agosto de 2019): 931–34. http://dx.doi.org/10.1094/mpmi-01-19-0010-a.

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Colletotrichum siamense causes fruit or foliar disease called anthracnose on a variety of plant hosts such as vegetables, fruits, ornamental plants, and others, including chili pepper, apple, American cranberry, mango, orange, papaya, guava, rubber plant, jasmine, coffee berry, and tea plants. Here, we report the first Illumina-sequenced draft genome assembly of C. siamense strain ICMP 18578 and its annotation. This genome sequence provides a unique resource that will be useful for future research on the evolution of Colletotrichum spp. and improvement of anthracnose management strategies.

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Ogoshi, Cláudio, Felipe Augusto Moretti Ferreira Pinto, Helon Santos Neto, Bruno Marques da Silva, Mário Sobral de Abreu y Mario Lúcio Vilela de Resende. "Viability and susceptibility of propagation material from coffee plants to Colletotrichum sp." Semina: Ciências Agrárias 36, n.º 6 (9 de diciembre de 2015): 3539. http://dx.doi.org/10.5433/1679-0359.2015v36n6p3539.

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This study aimed to verify the viability of propagation material from coffee plants descended from germplasm susceptible to blister spot disease as well as its susceptibility to Colletotrichum sp. relative to commercial coffee cultivars. In the first experiment, fruits were harvested from plants with and without symptoms of blister spot and sowed in trays containing a commercial sterilized substrate. The percentages of germinated seeds, viable plantlets and seedlings were evaluated. In diseased tissues, pathogens were isolated and identified though a pathogenicity test. In the second experiment, ten commercial cultivars and one cultivar originating from plants with blister spot were inoculated with the pathogens to assess the severity of anthracnose. Significant differences were not observed with respect to seed germination. However, the viability of plantlets and seedlings was reduced in the cultivar originating from plants with blister spot (Genotype Originated from Diseased Plants-GODP). These plants showed characteristic symptoms of blister spot, including necrosis in the leaves and hypocotyls, wilting and death. In the necrotic lesions, we observed characteristic sporulation of Colletotrichum sp. The cultivar most susceptible to anthracnose in cotyledonary leaves was Catuaí Vermelho (GODP), which presented the highest area under the disease progress curve (AUDPC). In conclusion, the viability of propagation material from coffee plants that had descended from plants with symptoms of blister spot (GODP) was reduced compared with plants from other genotypes, although seed germination was not affected. Moreover, GODP species are more susceptible to Anthracnose on the cotyledonary leaves relative to the other analyzed commercial cultivars. This work is the first to report on different symptoms exhibited by seedlings originating from the seeds of plants with symptoms of blister spot.

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Piato, Kevin, Cristian Subía, Jimmy Pico, Darío Calderón, Lindsey Norgrove y François Lefort. "Organic Farming Practices and Shade Trees Reduce Pest Infestations in Robusta Coffee Systems in Amazonia". Life 11, n.º 5 (30 de abril de 2021): 413. http://dx.doi.org/10.3390/life11050413.

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Coffee agroforestry systems could reconcile agricultural and environmental objectives. While pests and diseases can reduce yield, their interactions with shade and nutrition have been rarely researched, and are particularly lacking in perennial systems. We hypothesized that intermediate shade levels could reduce coffee pests while excess shade could favor fungal diseases. We hypothesized that organic rather than mineral fertilization would better synchronize with nutrient uptake and higher nutrient inputs would be associated with reduced pest and disease damage due to higher plant vigor, yet effects would be less obvious in shaded plots as coffee growth would be light-limited. Using three-year-old trees of Coffea canephora var. Robusta (robusta coffee) in the Ecuadorian Amazon, we compared a full-sun system with four shading methods creating different shade levels: (1) Myroxylon balsamum; (2) Inga edulis; (3) Erythrina spp.; or, (4) Erythrina spp. plus Myroxylon balsamum. Conventional farming at either (1) moderate or (2) intensified input and organic farming at (3) low or (4) intensified input were compared in a split-plot design with shade as the main plot factor and farming practice as the sub-plot factor. The infestation of the following pests and disease incidences were evaluated monthly during the dry season: brown twig beetle (Xylosandrus morigerus), coffee leaf miner (Leucoptera coffeella), coffee berry borer (Hypothenemus hampei), anthracnose disease (Colletotrichum spp.), thread blight (Pellicularia koleroga), and cercospora leaf spot (Cercospora coffeicola). Coffee berry borer and brown twig beetle infestation were both reduced by 7% in intensified organic treatments compared to intensified conventional treatments. Colonization of coffee berry borer holes in coffee berries by the entomopathogenic fungus Beauveria bassiana was also assessed. Brown twig beetle infestation was significantly higher under full sun than under Inga edulis, yet no other shade effects were detected. We demonstrate for the first time how intensified input use might promote pest populations and thus ultimately lead to robusta coffee yield losses.

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Thuy Hoai, Pham Thi. "IMPROVEMENT OF SOIL QUALITY, PREVENTION OF PLANT DISEASES AND YIELD INCREASE OF BLACK PEPPER AND COFFEE USING POLYFA-TN3". Vietnam Journal of Science and Technology 55, n.º 4C (24 de marzo de 2018): 44. http://dx.doi.org/10.15625/2525-2518/55/4c/12128.

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In the current study, we used bio-organic product POLYFA-TN3 including beneficial indigenous microorganisms isolated in Tay Nguyen to improve soil quality, prevent plant diseases, and increase the yield of black pepper and coffee in Dak Lak province. Experimental results showed the efficiency of using POLYFA-TN3 on improvement of soil quality. Almost parameters of soil were increased after using POLYFA-TN3, of which soluble N, K, and P were significantly increased. Using POLYFA-TN3 also reduced plant diseases of black pepper and coffee such as yellow leaf, slow wilt decline, anthracnose, Phytophthora root rot, coffee rust. Using 2.0 kg POLYFA-TN3/tree post showed that plant diseases dropped to 0.5 - 7.53 % for black pepper, and 0 % for coffee. In addition, the yield of black pepper and coffee was significantly increased, with 35.2 % and 31.1 %, respectively. Our study indicated that the bio-organic product POLYFA-TN3 as a potential product for improvement of soil quality, crop yield, and prevention of plant diseases.

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Serrato-Diaz, Luz M., Yobana A. Mariño y Paul Bayman. "Pathogens Causing Anthracnose and Fruit Rots of Coffee Associated with the Coffee Berry Borer and the Entomopathogenic Fungus Beauveria bassiana in Puerto Rico". Phytopathology® 110, n.º 9 (septiembre de 2020): 1541–52. http://dx.doi.org/10.1094/phyto-02-20-0057-r.

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Fruit rots reduce coffee production worldwide. Eight Colletotrichum species have been reported to cause coffee fruit rots; the most important is C. kahawae, the cause of coffee berry disease (CBD) in Africa. It is unknown whether these fruit rot pathogens can be dispersed by the coffee berry borer (CBB, Hypothenemus hampei) or whether Beauveria bassiana (a natural enemy of CBB) might reduce coffee fruit rots. We identified pathogens causing coffee fruits rots in Puerto Rico and evaluated whether B. bassiana reduced fruit rot and whether CBB could disperse pathogens. A total of 2,333 coffee fruit with CBB damage were collected; of these, 1,197 had visible growth of B. bassiana. C. fructicola, C. siamense, C. theobromicola, and C. tropicale were isolated and identified from the fruit using morphological traits and phylogeny of three nuclear genes. All four species caused internal and external rot after inoculation of healthy green coffee fruit. Coffee fruit treated with B. bassiana had significantly less fruit rot than untreated fruit, suggesting B. bassiana can protect against fruit rot. To test whether B. bassiana had a protective effect, B. bassiana and Colletotrichum were coinoculated on coffee fruit. Fruit inoculated with both B. bassiana and Colletotrichum had significantly less rot than fruit inoculated with Colletotrichum alone. To test if CBBs dispersed the pathogens, CBBs were exposed to Colletotrichum conidia and placed on green fruit, which resulted in fruit rot. This study identifies new pathogens causing coffee fruit rot, shows that C. kahawae is not the only Colletotrichum that attacks green fruits, suggests a role for B. bassiana in disease management and demonstrates CBB can disperse the pathogens.

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Nguyen, Phuong Thi Hang, Olga Vinnere Pettersson, Peter Olsson y Erland Liljeroth. "Identification of Colletotrichum species associated with anthracnose disease of coffee in Vietnam". European Journal of Plant Pathology 127, n.º 1 (22 de diciembre de 2009): 73–87. http://dx.doi.org/10.1007/s10658-009-9573-5.

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Meng, Yanan, Yihua Ren, Wenjing Wang, Mark L. Gleason, Rong Zhang y Guangyu Sun. "A Genome Sequence Resource for the Geographically Widespread Anthracnose Pathogen Colletotrichum asianum". Plant Disease 104, n.º 8 (agosto de 2020): 2044–47. http://dx.doi.org/10.1094/pdis-01-20-0034-a.

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Colletotrichum asianum is a worldwide plant pathogen causing serious fruit or leaf anthracnose diseases on a variety of plant hosts such as mango, coffee berry, chili, and other potential hosts, and it is distributed widely in Asia, America, Africa, and Oceania. This is the first genome resource available for C. asianum. The draft genome assembly will allow further analysis of species diversity and evolutionary mechanisms, and may serve as a foundation for genetic analysis that leads to greater understanding of interactions between plants and fungal pathogens.

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Rodríguez, Gabriel Alfonso Alvarez, Mario Sobral de Abreu, Felipe Augusto Moretti Fereira Pinto, Ana Cristina Andrade Monteiro, Ándres Mauricio Pinzón Núñez, Mario Lucio Vilela de Resende, Jorge Teodoro de Souza y Flavio Henrique Vasconcelos de Medeiros. "Phialomyces macrosporus decreases anthracnose severity on coffee seedlings by competition for nutrients and induced resistance". Biological Control 103 (diciembre de 2016): 119–28. http://dx.doi.org/10.1016/j.biocontrol.2016.08.009.

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Armesto, Cecilia, Fernanda Gonçalves Martins Maia, Fernando Pereira Monteiro y Mário Sobral de Abreu. "exoenzymes as a pathogenicity factor for Colletotrichum gloeosporioides associated with coffee plants". Summa Phytopathologica 45, n.º 4 (octubre de 2019): 368–73. http://dx.doi.org/10.1590/0100-5405/191071.

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ABSTRACT Phytopathogenic fungi during the penetration and colonization process are capable of secreting several enzymes, which enable infection of the host live tissue, acting on the degradation of wax, cuticle and cell walls. The ability of a pathogenic agent to produce enzymes or not can determine the severity degree of a disease. In this study, 33 isolates of Colletotrichum gloeosporioides related to anthracnose and blister spot on coffee trees were evaluated for their ability to produce hydrolytic enzymes (amylase, lipase, protease, laccase, pectinase and cellulase) and specific cell wall degrading enzymes “CWDEs” (polygalacturonase, polymethylgalacturonase and pectin-lyase), as well as their relationship with the pathogenicity/aggressiveness of isolates. For all isolates of C. gloeosporioides, extracellular enzymes could be detected, except cellulases. Isolates I-9 and I-24 produced the highest levels of extracellular enzymes, as well as CWDEs. They also had the highest disease intensity indexes, suggesting a relationship between enzymes and aggressiveness of the isolates.

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Mosquera-Sánchez, L. P., P. A. Arciniegas-Grijalba, M. C. Patiño-Portela, B. E. Guerra–Sierra, J. E. Muñoz-Florez y J. E. Rodríguez-Páez. "Antifungal effect of zinc oxide nanoparticles (ZnO-NPs) on Colletotrichum sp., causal agent of anthracnose in coffee crops". Biocatalysis and Agricultural Biotechnology 25 (mayo de 2020): 101579. http://dx.doi.org/10.1016/j.bcab.2020.101579.

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Somdej, Kanokmedhakul, Vilavong Somlit, Kanokmedhakul Kaunchai y Kasem Soytong. "Nano-particle derived from chaetomium cuprem cc3003 against Anthracnose of coffee var. Arabica". International Journal of Plant Biology 9, n.º 1 (21 de diciembre de 2018). http://dx.doi.org/10.4081/pb.2018.7736.

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Colletotrichum gloeosporioides is proved to be a pathogenic isolate causing anthracnose disease on coffee var. Arabica in Lao PDR. Chaetomium cupreum CC3003 inhibits sporulation of C. gloeosporiodes by 42.60 % in 30 days. The tested nano CCH, nano CCE and nano CCM derived from C. cupreum CC3003 significantly inhibits C. gloeosporioides that cause coffee anthracnose at low concentrations of about 3-15 ppm. The tested nano-particles applied to inoculated coffee seedlings significantly reduce coffee anthracnose. Research and development on nano-particles extracted from fungi are necessary to discover new strategies to control plant disease.

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Shi, Xinchi, Suyan Wang, Xuchu Duan, Xing Gao, Xinyu Zhu y Pedro Laborda. "First Report of Colletotrichum brevisporum Causing Soybean Anthracnose in China". Plant Disease, 6 de octubre de 2020. http://dx.doi.org/10.1094/pdis-09-20-1910-pdn.

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In March 2020, widespread anthracnose was observed on soybean (Glycine max) in southeastern Jiangsu (Nantong municipality; 120.53° E, 31.58° N) in China. Plants exhibited irregular brown necrotic lesions in stem and leaves, and pronounced wilting. The symptoms were detected in one soybean field, 0.42 ha, surrounded by healthy wheat fields. Approximately 65% of the soybean plants showed the disease symptoms, and crop yield was reduced by 28-35% with respect the yield achieved in previous years, when no symptoms were observed. The symptoms were consistent with those previously reported for anthracnose on soybean caused by Colletotrichum chlorophyti, C. cliviae and C. gloeosporioides (Barbieri et al. 2017; Mahmodi et al. 2013; Yang et al. 2012). Diseased, 3-week old plants were collected. Small pieces, approximately 1 cm2 in size, of symptomatic tissue were surface sterilized in 1.5% NaOCl for 1 min, and washed twice with sterile ddH2O. The pathogen was isolated and cultured on potato dextrose agar (Song et al. 2020), containing chloramphenicol (50 µg/mL), under darkness at 28 °C for 3 days. Sequence of internal transcribed spacer (ITS), actin (ACT), β-tubulin (TUB2) and glyceraldehyde 3-phosphate dehydrogenase (GAP/span>DH) genes was performed as reported by Yang et al. (2015). Sequences were submitted to GenBank under accession numbers MT361074 (ITS) and MT415548-MT415550 (ACT, TUB2 and GAPDH). Blast search revealed that the amplified sequences had 100% (ITS; C. brevisporum TCHD, MH883805), 97.66% (ACT; C. brevisporum S38, KY986905), 99.06% (TUB2; C. brevisporum PF-2, KY705061) and 100% (GAPDH; C. brevisporum LJTJ27, KP823797) matches to multiple C. brevisporum strains, whereas all reported C. chlorophyti, C. cliviae and C. gloeosporioides strains showed no similarity to at least 2 of the studied genes. Molecular phylogenetic tree constructed using MEGA7 confirmed the identity of the pathogen. ACT and ITS sequences were blasted separately in Muscle (https://www.ebi.ac.uk/Tools/msa/muscle/) and then combined together to make the phylogenetic tree. The evolutionary history was inferred by using the Maximum Likelihood method based on the Tamura 3-parameter model, and the tree with the highest log likelihood (-1749.2186) is shown in Figure 1. The Colletotrichum strains previously found causing anthracnoseon soybean, and other relevant strains used in taxonomic analyses were included in the phylogenetic tree. Microscope observations showed the presence of 15-µm-long cylindrical conidia and septate mycelium, and agree with those reported for the morphology of C. brevisporum by Damm et al. (2019). To confirm pathogenicity, the mycelia from a 2 day-old culture on PDA was collected and suspended in sterile ddH2O (≈ 106 cells/mL) to prepare the inoculum. The pathogen was sprayed-inoculated on stem and leaves of healthy soybean plants. In control plants, sterile ddH2O was used. Inoculated plants were maintained in growth chamber at 28 °C and 50% relative humidity. Typical anthracnose symptoms were obsered 20 days after inoculation (Figure 2). C. brevisporum was reported to produce anthracnose on pumpkin, papaya, mulberry, coffee, passion fruit and pepper in China (Liu et al. 2017; Liu et al. 2019; Xue et al. 2019). Here, we report for the first time C. brevisporum causing anthracnose on soybean, an economically-relevant crop in China.

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Vilavong, Somlit y Kasem Soytong. "Application of A New Bio-Formulation of Chaetomium cupreum For Biocontrol of Colletotrichum gloeosporioides Causing Coffee Anthracnose on Arabica Variety in Laos". AGRIVITA Journal of Agricultural Science 39, n.º 3 (1 de octubre de 2017). http://dx.doi.org/10.17503/agrivita.v39i3.1070.

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Ismail, Siti Izera, Nur Liyana Mohmad Zaiwawi, Sumaiyah Abdullah, Syari Jamian y Norsazilawati Saad. "First Report of Colletotrichum siamense causing Anthracnose on White Frangipani (Plumeria alba L.) in Malaysia". Plant Disease, 15 de abril de 2021. http://dx.doi.org/10.1094/pdis-12-20-2614-pdn.

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Plumeria alba L. is a flowering plant in the family Apocynaceae and widely cultivated in Malaysia as a cosmopolitan ornamental plant. In January 2020, anthracnose lesions were observed on leaves of Plumeria alba planted in Agricultural Farm, Universiti Putra Malaysia, in Selangor state, Malaysia. The disease mainly affected the leaves with symptoms occurring with approximately a 60% disease incidence. Ten symptomatic leaves were sampled from 3 different trees in the farm. Symptoms initiated as small circular necrotic spots that rapidly enlarged into black lesions with pale brown borders. Diseased tissues (5×5 mm) were surface-sterilized with 70% ethanol for 1 min, rinsed three times with sterile distilled water, dried on sterile filter papers, plated on PDA and, incubated at 25 °C with a 12-h photoperiod. A total of seven single-spore isolates with similar colony morphologies were obtained from tissue samples. After 7 days, the colonies raised the entire margin and showed white-to-gray aerial mycelium, orange conidial masses in the center and appeared dark brown at the center of the reverse view. The conidia were 1-celled, hyaline, smooth-walled, cylindrical with narrowing at the center, averaged (13-15 μm × 3 - 4 μm) (n=40) in size. Morphological characteristics of the isolates were similar to those detailed in taxonomic description of Colletotrichum sp. (Prihastuti et al. 2009). For molecular identification, genomic DNA of two representative isolates, PL3 and PL4 was extracted from fresh mycelium using DNeasy Plant Mini Kit (Qiagen, USA). The internal transcribed spacer (ITS) region, actin (ACT) and calmodulin (CAL) genes were amplified using ITS5/ITS4 (White et al. 1990), ACT-512F/783R (Carbone and Kohn 1999) and CL1C/CL2C primer sets (Weir et al. 2012). A BLAST nucleotide search of GenBank using ITS sequences showed 100% identity to Colletotrichum siamense ex-type culture ICMP 18578 (GenBank accession no. JX010171). ACT and CAL sequences showed 100% identity with C. siamense ex-type isolate BPD-I2 (GenBank accession no. FJ907423 and FJ917505). The sequences were deposited in GenBank (ITS: accession nos. MW335128, MT912574), ACT: accession nos. MW341257, MW341256, CAL: accession nos. MW341255 and MT919260). Based on these morphological and molecular characteristics, the fungus was identified as C. siamense. Pathogenicity of PL3 and PL4 isolates was verified using four healthy detached leaves of Plumeria alba. The leaves were surface-sterilized using 70% ethanol and rinsed twice with sterile water before inoculation. The leaves (three inoculation sites/leaf) were wounded by puncturing with a sterile needle through the leaf cuticle and inoculated in the wound site with 10-μl of conidial suspension (1×106 conidia/ml) from 7-days-old culture on PDA. Four leaves were used as a control and were inoculated only with 10-μl of sterile distilled water. Inoculated leaves were kept in humid chambers for 2 weeks at 25 °C with 98% relative humidity on a 12-h fluorescent light/dark period. The experiment was repeated three times. Anthracnose symptoms were observed on all inoculated leaves after 3 days, whereas controls showed no symptoms. Fungal isolates from the diseased leaves showed the same morphological characteristics as isolates PL3 and PL4, confirming Koch’s postulates. C. siamense has been reported causing anthracnose on rose (Rosa chinensis) in China (Feng et al. 2019), Coffea arabica in Thailand (Prihastuti et al. 2009) and mango leaf anthracnose in Vietnam (Li et al. 2020). To our knowledge, this is the first report of Colletrotrichum siamense causing leaf anthracnose on Plumeria alba in Malaysia. Accurate identification of this pathogen provides a foundation in controlling anthracnose disease on Plumeria alba.

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Artículos de revistas sobre el tema "Coffee anthracnose"

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