To see the other types of publications on this topic, follow the link: Blossom blight.
Journal articles on the topic 'Blossom blight'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 journal articles for your research on the topic 'Blossom blight.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse journal articles on a wide variety of disciplines and organise your bibliography correctly.
1
Luo, Y., D. P. Morgan, and T. J. Michailides. "Risk Analysis of Brown Rot Blossom Blight of Prune Caused by Monilinia fructicola." Phytopathology® 91, no. 8 (2001): 759–68. http://dx.doi.org/10.1094/phyto.2001.91.8.759.
Full textAbstract:
Experiments under controlled environmental conditions were conducted during bloom of prune (Prunus domestica, L.) in 1999 and 2000 to assess the effects of inoculum concentration (IC), wetness duration (WD), temperature, and bloom stages on development of brown rot blossom blight of prunes. Branches from trees of a prune orchard were inoculated with Monilinia fructicola at different bloom stages and incubated at different temperatures with different periods of WD. The proportion of blighted blossoms (PBB) for each inoculated branch was determined. Bloom stage, IC, temperature, and WD significantly affected blossom blight of prunes. PBB at popcorn and full bloom stages was significantly greater than PBB at later bloom stages (P ≤0.05). The optimal temperatures for blossom blight development were 22 to 26°C, and Gaussian functions were used to describe the relationship between PBB and temperature. PBB linearly increased with increased IC. Linear regressions of PBB on WD were obtained for each combination of bloom stage, IC, and temperature. The parameters of these regressions were used in a computer program to produce the possible maximum PBB with 90% probability (PBB90) using stochastic simulations. Early bloom stages with a higher IC at temperatures from 20 to 25°C were associated with more severe blossom blight than late stages with a lower IC at nonoptimal temperatures. Blossom blight did not occur at <10 or >30°C and less than 4-h WD. However, longer than 4-h WD linearly increased incidence of blossom blight. A risk assessment table of blossom blight was produced for different environmental conditions to guide the control of prune brown rot.
2
Ferrada, Enrique E., Bernardo A. Latorre, Juan P. Zoffoli, and Antonio Castillo. "Identification and Characterization of Botrytis Blossom Blight of Japanese Plums Caused by Botrytis cinerea and B. prunorum sp. nov. in Chile." Phytopathology® 106, no. 2 (2016): 155–65. http://dx.doi.org/10.1094/phyto-06-15-0143-r.
Full textAbstract:
Blossom blight is a destructive disease of plums (Prunus salicina) when humid and temperate weather conditions occur in Chile. Disease incidence ranging from 4 to 53% has been observed. Symptoms include light brown petal necrosis, starting as light brown mottles or V-shaped necrosis at the margins of the petals, progressing to the stamen and pistils. In this study, the etiology of blossom blight of plums was determined. High- and low-sporulating isolates of Botrytis were obtained consistently from blighted blossoms and apparently healthy flowers of plums. Based on colony morphology, conidial production and molecular phylogenetic analysis, these high- and low-sporulating isolates were identified as B. cinerea and B. prunorum sp. nov., respectively. Phylogenetic analysis of the genes glyceraldehyde 3-phosphate dehydrogenase (G3PDH), heat-shock protein 60 (HSP60), and DNA-dependent RNA polymerase subunit II (RPB2) grouped B. prunorum isolates in a single cluster, distantly from B. cinerea and other Botrytis species. The phylogenetic analysis of necrosis and ethylene-inducing protein (NEP1 and NEP2) genes corroborated these results. Analysis of the internal transcribed spacer region and large-subunit (26S) ribosomal DNA and detection of Boty and Flipper transposable elements, were not useful to differentiate between these Botrytis species. Both species were pathogenic on plum flowers and the fruit of plums, apples, and kiwifruits. However, B. prunorum was less virulent than B. cinerea. These pathogens were re-isolated from inoculated and diseased tissues; thus, Koch’s postulates were fulfilled, confirming its role in blossom blight of plums. B. cinerea was predominant, suggesting that B. prunorum may play a secondary role in the epidemiology of blossom blight in plums in Chile. This study clearly demonstrated that the etiology of blossom blight of plums is caused by B. cinerea and B. prunorum, which constitute a species complex living in sympatry on plums and possibly on other stone fruit trees.
3
Holb, I. J., and G. Schnabel. "Effect of Fungicide Treatments and Sanitation Practices on Brown Rot Blossom Blight Incidence, Phytotoxicity, and Yield for Organic Sour Cherry Production." Plant Disease 89, no. 11 (2005): 1164–70. http://dx.doi.org/10.1094/pd-89-1164.
Full textAbstract:
Demand for organically grown fruit, including sour cherry, is rising in Europe and the United States, but the limited tools for disease management have not been thoroughly investigated. In this study, management of brown rot blossom blight, caused by Monilinia laxa, was examined for organic sour cherry production in Hungary. Combinations of sanitation practices and fungicide treatments, including copper hydroxide, lime sulfur, and micronized and nonmicronized wettable sulfur, were investigated in 2 years and two cultivars. The effect of fungicide treatments on yield and phytotoxicity on spur-leaf clusters was also determined. Among fungicide treatments suitable for organic production, copper hydroxide and lime sulfur alone or in combination with micronized wettable sulfur were most effective for blossom blight control when applied twice (at closed blossom and full bloom) or three times (at closed blossom, full bloom, and petal fall) during bloom. Both treatments were not as effective as the conventional standard and caused more damage on spur-leaf clusters during wet weather conditions, but significantly increased crop yield compared with the untreated control or wettable sulfur treatments. Micronized and nonmicronized sulfur applied up to three times during bloom were equally effective, did not impact yield, were not phytotoxic, and reduced blossom blight compared with the untreated control. Sanitation (the removal of blighted twigs and mummified fruit) reduced blossom blight in both cultivars compared with nonsanitized plots when disease pressure was high. The need for an integrated approach to effectively manage blossom blight in organic sour cherry production is discussed. This is the first in-depth characterization of cultural and chemical brown rot blossom blight control options for organic sour cherry production.
4
Koball, D. C., W. F. Wilcox, and R. C. Seem. "Influence of Incubation-Period Humidity on the Development of Brown Rot Blossom Blight of Sour Cherry." Phytopathology® 87, no. 1 (1997): 42–49. http://dx.doi.org/10.1094/phyto.1997.87.1.42.
Full textAbstract:
When detached sour cherry (Prunus cerasus) blossoms were inoculated with conidia of Monilinia fructicola and subjected to a standard 8-h wetting treatment at 20°C, blossom blight incidence was proportional to relative humidity (RH) when RH was held constant during the subsequent 6-day incubation period (frequency = 1.0 at the maximum RH of 92%; frequency = 0.38 at the minimum RH of 57%). Similarly, when a primary incubation period at 87% RH was followed by a secondary incubation period at 54% RH, blossom blight incidence was proportional to the number of hours at the higher level (frequencies of 0.94, 0.80, and 0.38 with primary incubation periods of 6 days, 36 h, and 12 h, respectively). When intact blossoms on potted trees were exposed to common inoculation and wetting treatments, disease incidence was consistently high on trees that subsequently were incubated in a controlled environment chamber (20°C, 90 to 95% RH) but was extremely variable when trees were incubated under variable ambient conditions. Ambient incubation temperature had little effect on disease incidence 9 days after inoculation, whereas ambient RH had a pronounced effect: the frequency of blighted blossoms was 0.53 to 0.61 when the number of hours at RH >90% was approximately two to six times that at RH <60%, whereas this frequency was only 0.02 to 0.07 when the number of hours at RH >90% was approximately one-third the number at RH <60%. After 48 h at a constant RH of 89 or 57%, the water potential of excised uninoculated blossoms was -1.15 and -1.93 MPa, respectively; however, growth of M. fructicola on osmotically adjusted potato dextrose agar was unaffected by changes in water potential within this range. Thus, although RH during incubation has an important influence on blossom blight development, the causal mechanism remains uncertain.
5
Mullen, J. M., A. K. Hagan, and D. K. Carey. "First Report of Phytophthora Blossom Blight of Chrysanthemum Caused by Phytophthora nicotianae." Plant Disease 85, no. 8 (2001): 923. http://dx.doi.org/10.1094/pdis.2001.85.8.923b.
Full textAbstract:
In October 2000, chrysanthemums (Dendranthema × grandiflorum) cv. Debonair exhibiting blossom blight were submitted to the Plant Diagnostic Lab at Auburn University by a commercial greenhouse where most of the potted plants of this cultivar were symptomatic. At a local retail outlet, approximately 95% of the plants of the same cultivar of chrysanthemum had a similar blossom blight. Blighted petals were examined microscopically, and nonpapillate, internally proliferating sporangia (40 to 45 μm in length), characteristic of some species of Phytophthora, were observed. A species of Phytophthora was isolated repeatedly on PARP selective medium (corn meal agar containing pimaricin, ampicillin, rifamycin, and pentachloronitrobenzene). Isolates recovered were grown on V8 juice agar, under fluorescent lights and in darkness, at room temperature. These isolates were identified as Phytophthora nicotianae (= Phytophthora parasitica), on the basis of morphological and cultural characteristics. Sporangia were papillate (including some with dual apices), noncaducous, 45 to 60 μm in length, and spherical, ovoid, or obpyriform. Mycelium growth occurred at 36°C. Isolates were considered heterothallic because they did not produce oospores when grown on V8 juice agar in the dark for 2 weeks. Sporangia that were nonpapillate and proliferating internally were not observed on any of these isolates. Because we apparently did not isolate the Phytophthora spp. seen microscopically on petals, we cannot comment on its exact identity or significance in causing this disease. We did conduct pathogenicity tests to determine whether isolates of P. nicotianae were capable of causing the observed symptoms. These tests were conducted twice on chrysanthemum cultivars Debonair, Yellow Triumph, Spotlight, Raquel, Jennifer, Grace, and Hot Salsa. In the first test, two plants of each cultivar were sprayed to runoff with a zoospore suspension (105 spores per ml) in sterile, filtered water. Two plants of each cultivar were sprayed with sterile, filtered water as noninoculated controls. Individual plants were placed in loosely closed plastic bags, misted daily, and held at 23 to 24°C with indirect lighting (approximately 12 h per day) for 1 week. In the second test, four plants of each cultivar except Debonair were inoculated as described previously, four plants of each cultivar were left untreated as noninoculated controls, and one Debonair plant was inoculated and one remained noninoculated. Plants were held for 3 days in an environmentally controlled growth room, with 23°C days (11 h)-20°C nights (13 h), under a plastic tent where high levels of humidity were maintained with a humidifier and daily misting. A grow light provided a low level of lighting (4 to 6 μE · m-2 · s-1). All inoculated plants developed severe blossom blight similar to that observed initially. In the first test, symptoms were evident at 2 days. In the growth room, blossom blight first was observed at 24 h postinoculation. In both tests, blossom blight severity increased quickly in the 1 to 2 days after the initial occurrence of symptoms. Only blossoms became diseased; symptoms did not extend to other plant organs. P. nicotianae was reisolated consistently from symptomatic blossoms on selective medium. This is, we believe, the first report of blossom blight on chrysanthemum caused by a species of Phytophthora. Previously, P. nicotianae has been reported to cause leaf blight on artificially inoculated Chrysanthemum × morifolium (Dendranthema × grandiflorum) cultivars Capri and Vermilion in Florida (1) and twig and leaf blight on Chrysanthemum coronarium in India (2). References: (1) C. R. Semer and B. C. Raju. Plant Dis. 69:1005–1006, 1985. (2) N. Sushma and N. D. Sharma. J. Mycol. Plant Pathol. 27:345, 1997.
6
Wallis, Anna E., and Kerik D. Cox. "Management of Fire Blight Using Pre-bloom Application of Prohexadione-Calcium." Plant Disease 104, no. 4 (2020): 1048–54. http://dx.doi.org/10.1094/pdis-09-19-1948-re.
Full textAbstract:
Fire blight, a bacterial disease of rosaceous plants caused by Erwinia amylovora, is one of the most important diseases affecting commercial apple production worldwide. Antibiotics, applied at bloom to protect against blossom infection, are the most effective means of management but raise concern due to the potential for antibiotic resistance in both the pathogen population and nontarget organisms. In addition, most fire blight outbreaks in New York State often emerge in late June to July as shoot blight, calling into question the role of blossom infections and the antibiotic applications made to manage them. Prohexadione-calcium (PhCa) is a gibberellic acid inhibitor used post-bloom to control shoot vigor and to manage shoot blight. However, the magnitude of shoot blight management is directly related to the suppression of shoot growth, which is undesirable, especially in young orchards during establishment years. PhCa is believed to control shoot blight by thickening cell walls in cortical parenchyma, preventing invasion of host tissues by E. amylovora. We hypothesize that PhCa applied pre-bloom could similarly prevent invasion of blossom pedicels following infection, leading to reduced disease incidence. We evaluated novel pre-bloom PhCa programs for their effects on disease management (blossom and shoot blight) as well as their impact on shoot growth for three years in a mature ‘Gala’ orchard in New York. In all three years of the study, all PhCa programs resulted in less than 27% incidence (71% control) of blossom blight and less than 13% incidence (77% control) of shoot blight with minimal effect on tree growth. Inclusion of a biopesticide during bloom further reduced the incidence of blossom blight in one year of three. Using light microscopy, we found that cell walls in the cortical parenchyma of fruitlet pedicels on trees receiving pre-bloom PhCa applications were significantly thicker than those of untreated trees 40 days after full bloom and inoculation. Overall, we found that pre-bloom applications of PhCa had utility in reducing blossom blight and shoot blight with minimal impacts on tree growth. These pre-bloom programs would fit with standard production practices and may contribute toward the development of fire blight management programs without the use of antibiotics.
7
Finn, Chad, Gina Koskela, and Joseph Snead. "524 PB 492 SEVERITY OF BOTRYTIS BLOSSOM BLIGHT DAMAGE ON BLUEBERRY CULTIVARS AND SELECTIONS." HortScience 29, no. 5 (1994): 506e—506. http://dx.doi.org/10.21273/hortsci.29.5.506e.
Full textAbstract:
Infestations of Botrytis blossom blight (Botrytis cinerea) can reduce yields in commercial blueberry fields in the Pacific Northwest. In 1993, environmental conditions during blueberry flowering were ideal for the development of Botrytis. Individual plants were evaluated in a replicated highbush blueberry culture/advanced selection trial (42 clones, 5 reps, 3 plants) in Aurora, Ore. Each plant was evaluated for damage due to Botrytis using a subjective scoring system (1= all flower clusters on plant appear blighted, 5= many blossoms blighted, 9= no blossoms blighted). Many clones showed very little injury. The following clones showed the greatest injury, in decreasing order of severity, NC 2678, `Bluechip', `Bounty', G-805, `Nelson', G-224, `Berkeley', `Sierra', and `Bluegold'. In addition, Botrytis damage was scored on the field collection of Vaccinium at the National Clonal Germplasm Repository. Data from this nonreplicated study will also be presented.
8
Gschwend, Florian, Andrea Braun-Kiewnick, Franco Widmer, and Cosima Pelludat. "Apple Blossoms from a Swiss Orchard with Low-Input Plant Protection Regime Reveal High Abundance of Potential Fire Blight Antagonists." Phytobiomes Journal 5, no. 2 (2021): 145–55. http://dx.doi.org/10.1094/pbiomes-04-20-0033-r.
Full textAbstract:
Erwinia amylovora causes fire blight, a serious disease of Rosaceae plants, including apple and pear. A predominant path of bacterial infection is entry through nectartodes after multiplication on the stigma. Depending on the inhibitory abilities of the native blossom microbiota, it may control the outbreak of fire blight and, therefore, may bar potential plant protection with reduced input of synthetic chemicals. Blossoms of five apple varieties in a low-input orchard, which had no fire blight history despite disease outbreaks in close proximity, were analyzed to assess bacterial and fungal communities. Metabarcoding indicated low microbial diversity and the presence of a few dominant operational taxonomic units (OTUs), including known fire blight antagonists such as Metschnikowia pulcherrima and Aureobasidium pullulans. The most dominant bacterial taxon (bOTU_01) was classified as Erwinia spp. To resolve sequences of species within bOTU_01, we used analyses of sequence variants and DNA signatures (i.e., nucleotide polymorphisms that are indicative for different species or species groups). These analyses revealed that >94.5% of the sequences of bOTU_01 derived from E. tasmaniensis, a potential E. amylovora antagonist. The latter was represented by up to 0.006% of the sequences. Cultivation-based analyses confirmed the prevalence of E. tasmaniensis. The high abundance of native potential E. amylovora antagonists likely indicates that this special set of native apple blossom microbiota counteracted the establishment of E. amylovora in this low-input orchard. This may allow for a new approach to assess possible components of synthetic apple blossom communities to mitigate fire blight infections.
9
Seijo, T. E., R. J. McGovern, and A. Marenco de Blandino. "Petal Blight of Sunflower Caused by Itersonilia perplexans." Plant Disease 84, no. 10 (2000): 1153. http://dx.doi.org/10.1094/pdis.2000.84.10.1153b.
Full textAbstract:
In February 1999, a cut-flower grower from Florida reported post-harvest losses of approximately 25% in Helianthus annuus (sunflower) cvs. Sunrich Orange and Sunbright. Symptoms began as small, pinpoint brown lesions on the petals, which enlarged and coalesced, leading to necrosis of the entire blossom. Symptomatic petals were surface disinfested for 30 sec with 0.5% NaOCl and suspended over plates containing acidified 25% potato-dextrose agar. Petals adhered to lids of the petri dishes by the surface tension of the water on the petals. Itersonilia perplexans Derx was consistently isolated. Inoculation of sunflower with I. perplexans was achieved using three detached, mature blossoms of the cv. Sundance Kid with their pedicels placed in sterile water. Each blossom was inoculated with 3.5 ml of a spore suspension (1 × 105 spores/ml) applied as a spray. Three noninoculated control blossoms were sprayed with sterile, distilled water. Blossoms were incubated in a controlled environment chamber at near 100% RH, a constant temperature of 18°C, and a 12-h photoperiod. Three days following inoculation all of the inoculated blossoms were symptomatic, with necrosis ranging from 50 to 100% on individual petals. I. perplexans was recovered from all of the inoculated blossoms. Noninoculated controls remained symptomless, and I. perplexans was not recovered. I. perplexans has been reported to cause lesions on the cotyledons, first true leaves, and the hypocotyl region of sunflower seedlings in Canada and Uruguay (1,2). However, this is the first report of post-harvest petal blight in sunflower caused by I. perplexans and the first report in the United States of infection of sunflower by I. perplexans. References: (1) W. E. Sackston. Can. Phytopath. Soc. 1952:22, 1953. (2) W. E. Sackston. Phytopathology. 48:108, 1958.
10
Dowling, Madeline E., William C. Bridges, Brodie M. Cox, Tommy Sroka, Jennifer R. Wilson, and Guido Schnabel. "Preservation of Monilinia fructicola Genotype Diversity Within Fungal Cankers." Plant Disease 103, no. 3 (2019): 526–30. http://dx.doi.org/10.1094/pdis-05-18-0800-re.
Full textAbstract:
Monilinia fructicola is a destructive pathogen causing brown rot on stone fruits worldwide. Though it is best known as a fruit rot pathogen, M. fructicola also causes blossom blight and, subsequently, twig cankers in the spring. Orchard management strategies often overlook cankers as an inoculum source, though they are an inoculum source of both blossom and fruit infections. In this study, we analyzed the role of cankers as storage structures for diverse genotypes of M. fructicola, examining whether multiple genotypes can be transmitted from blossom to canker. Fungal spores from blossoms, and 2 months later from their corresponding cankers, were collected from a conventional and an unsprayed orchard in 2015 and 2016. Simple sequence repeat markers were used to genotype 10 to 20 single spores from each of four blossom/canker pairs per orchard. Individual blossoms and cankers were detected containing up to four and five genotypes, respectively. The average number of genotypes in blossoms and corresponding cankers were not significantly different (P = 0.690) across both years and farms, showing that a bottleneck for genetic diversity was not generated during the transition from blossom to canker. The average number of genotypes unique to blossom or canker was not significantly different (P = 0.569) and no significant effect of farm (P = 0.961) or year (P = 0.520) was observed, although blossoms had a numerically greater number of unique genotypes in both cases. In conclusion, a single blossom may be infected by one or more genotypes of M. fructicola, and this diversity is being preserved in the corresponding canker. This information implicates M. fructicola cankers as diversity storehouses, and may also apply to other Monilinia spp. and fungal diseases that initiate in reproductive tissue.
11
PARK, S. J., and B. N. DHANVANTARI. "TRANSFER OF COMMON BLIGHT (Xanthomonas campestris pv phaseoli) RESISTANCE FROM Phaseolus coccineus Lam. TO P. vulgaris L. THROUGH INTERSPECIFIC HYBRIDIZATION." Canadian Journal of Plant Science 67, no. 3 (1987): 685–95. http://dx.doi.org/10.4141/cjps87-096.
Full textAbstract:
Four interspecific backcross populations derived from hybridizations between Phaseolus vulgaris × (P. vulgaris × P. coccineus) were produced to transfer common blight (Xanthomonas campestris pv phaseoli) resistance from a blight–resistant accession of P. coccineus to P. vulgaris white bean cultivars and to determine the association between blight resistance and some agronomic characteristics. Frequency distribution of leaf blight resistance ratings in the BCF2 and BCF3 generations and of percent pod blight infection in the BCF3 generation appeared to be continuous, ranging between the respective parental resistance reactions. This indicated that the transfer of common blight resistance from P. coccineus to P. vulgaris was feasible. Scores for leaf and pod blight were not associated indicating differential blight resistance reactions of the two plant organs. Leaf blight was negatively correlated with days to blossom but was not correlated with growth habit and pod set except for one cross in which leaf blight and pod set were associated. Percent pod blight was negatively correlated with days to blossom in two crosses. Pod blight was not associated with growth habit and pod set except for one cross in which it was associated with pod set. Days to blossom and pod set were associated. Implications of these findings in the breeding of blight resistant white bean cultivars are discussed.Key words: Interspecific crosses, Phaseolus coccineus, Phaseolus vulgaris, Xanthomonas campestris pv phaseoli, common blight, correlation
12
Namkung, Kyung-Bong, and Sung Chul Yun. "Improvement of Fire Blight Blossom Infection Control Using Maryblyt in Korean Apple Orchards." Plant Pathology Journal 39, no. 5 (2023): 504–12. http://dx.doi.org/10.5423/ppj.oa.08.2023.0110.
Full textAbstract:
After transitioning from periodic to model-based control policy for fire blight blossom infection, it is crucial to provide the timing of field application with easy and accurate information. To assess the risk of blossom infection, <i>Maryblyt</i> was employed in 31 sites across apple-producing regions nationwide, including areas prone to fire blight outbreaks, from 2021 to 2023. In 2021 and 2023, two and seven sites experienced Blossom Infection Risk-Infection warning occurrences among 31 sites, respectively. However, in 2022, most of the sites observed Blossom Infection Risk-Infection from April 25 to 28, highlighting the need for blossom infection control. For the comparison between the two model-based control approaches, we established treatment 1, which involved control measures according to the Blossom Infection Risk-Infection warning and treatment 2, aimed at maintaining the Epiphytic Infection Potential below 100. The analysis of control values between these treatments revealed that treatment 2 was more effective in reducing Blossom Infection Risk-Infection and the number of days with Epiphytic Infection Potential above 100, with respective averages of 95.6% and 93.0% over the three years. Since 2022, the implementation of the K-Maryblyt system and the deployment of Automated Weather Stations capable of measuring orchard weather conditions, with an average of 10 stations per major apple fire blight county nationwide, have taken place. These advancements will enable the provision of more accurate and timely information for farmers based on fire blight models in the future.
13
Pleskatsevich, R. I. "DYNAMICS OF MONILIOSIS DEVELOPMENT AND THE EFFICIENCY OF APPLICATION OF THE FUNGICIDE INDIGO, CS TO CHERRY PLANTS (CERASUS VULGARIS MILL.)." Plant protection, no. 46 (October 21, 2022): 121–28. http://dx.doi.org/10.47612/0135-3705-2022-46-121-128.
Full textAbstract:
The paper presents the data on a long term dynamics of the occurrence and development of moniliosis in cherry plants. It’s established that during the research the occurrence of blossom blight of cherry sprouts was 1,6–59,7 %, and fruit rot – 0,2–27,4 %. The development of cherry blossom blight doesn’t depend on the age of the crop. The biological efficiency of the copper fungicide Indigo, CS was studied. The biological efficiency of Indigo, CS applied in a dose of 3,0–5,0 l/ha to cherry amounted to in 2020: 77,8–88,1 % for limitation of blossom blight of sprouts, and 86,0–92,0 % for limitation of fruit rot; in 2021: 77,8–83,0 % and 88,3–92,0 % respectively.
14
Wittig, H. P. P., K. B. Johnson, and J. W. Pscheidt. "Effect of Epiphytic Fungi on Brown Rot Blossom Blight and Latent Infections in Sweet Cherry." Plant Disease 81, no. 4 (1997): 383–87. http://dx.doi.org/10.1094/pdis.1997.81.4.383.
Full textAbstract:
Antagonistic effects of Aureobasidium pullulans, Epicoccum purpurascens, and Gliocladium roseum on establishment of Monilinia fructicola infections on cv. Royal Anne cherry blossoms were assessed in a mist chamber and under field conditions. Conidia of each fungus were applied to blossoms that were subsequently inoculated with conidia of M. fructicola. Mist chamber experiments on forced blossoms demonstrated that incidence of recovery of M. fructicola from blossoms was significantly reduced (P ≤ 0.05) to similar levels when either E. purpurascens or the fungicide benomyl had been applied 24 h prior to inoculation with M. fructicola. In field trials in 1990, 1991, and 1993, application of E. purpurascens reduced blossom blight relative to nontreated blossoms by 47, 58, and 45%, respectively; whereas application of A. pullulans caused reductions of 54, 13, and 47%, respectively. Comparable reductions in blossom blight for the fungicide iprodione were 80, 95, and 98%, respectively. Latent M. fructicola infections were evaluated by dipping immature green cherries in a dilute solution of the herbicide paraquat. Applications of E. purpurascens and A. pullulans to blossoms reduced the number of latent M. fructicola infections in green cherries by 24 and 48%, respectively, in 1990; 57 and 62%, respectively, in 1991; and 19 and 16%, respectively, in 1993. This compares with reductions of 95, 91, and 17% in 1990, 1991, and 1993, respectively, with the fungicide iprodione. E. purpurascens and G. roseum also were recovered from surface-disinfested, paraquat-dipped cherry fruit. Percent recovery of these fungi was significantly (P ≤ 0.05) higher from treatments where they had been applied to blossoms compared with the nontreated control.
15
Stockwell, V. O., K. B. Johnson, D. Sugar, and J. E. Loper. "Control of Fire Blight by Pseudomonas fluorescens A506 and Pantoea vagans C9-1 Applied as Single Strains and Mixed Inocula." Phytopathology® 100, no. 12 (2010): 1330–39. http://dx.doi.org/10.1094/phyto-03-10-0097.
Full textAbstract:
The biological control agents Pseudomonas fluorescens A506 and Pantoea vagans C9-1 were evaluated individually and in combination for the suppression of fire blight of pear or apple in 10 field trials inoculated with the pathogen Erwinia amylovora. The formulation of pathogen inoculum applied to blossoms influenced establishment of the pathogen and the efficacy of biological control. Pantoea vagans C9-1 suppressed fire blight in all five trials in which the pathogen was applied as lyophilized cells but in none of the trials in which the pathogen was applied as freshly harvested cells. In contrast, Pseudomonas fluorescens A506 reduced disease significantly in only one trial. A mixture of the two strains also suppressed fire blight, but the magnitude of disease suppression over all field trials (averaging 32%) was less than that attained by C9-1 alone (42%). The two biological control agents did not antagonize one another on blossom surfaces, and application of the mixture of A506 and C9-1 to blossoms resulted in a greater proportion of flowers having detectable populations of at least one bacterial antagonist than the application of individual strains. Therefore, the mixture of A506 and C9-1 provided less disease control than expected based upon the epiphytic population sizes of the antagonists on blossom surfaces. We speculate that the biocontrol mixture was less effective than anticipated due to incompatibility between the mechanisms by which A506 and C9-1 suppress disease.
16
Ahn, Mun-Il, Hyeon-Ji Yang, and Sung-Chul Yun. "Development of K-Maryblyt for Fire Blight Control in Apple and Pear Trees in Korea." Plant Pathology Journal 40, no. 3 (2024): 290–98. http://dx.doi.org/10.5423/ppj.oa.02.2024.0038.
Full textAbstract:
K-Maryblyt has been developed for the effective control of secondary fire blight infections on blossoms and the elimination of primary inoculum sources from cankers and newly emerged shoots early in the season for both apple and pear trees. This model facilitates the precise determination of the blossom infection timing and identification of primary inoculum sources, akin to Maryblyt, predicting flower infections and the appearance of symptoms on various plant parts, including cankers, blossoms, and shoots. Nevertheless, K-Maryblyt has undergone significant improvements: Integration of Phenology Models for both apple and pear trees, Adoption of observed or predicted hourly temperatures for Epiphytic Infection Potential (EIP) calculation, incorporation of adjusted equations resulting in reduced mean error with 10.08 degree-hours (DH) for apple and 9.28 DH for pear, introduction of a relative humidity variable for pear EIP calculation, and adaptation of modified degree-day calculation methods for expected symptoms. Since the transition to a model-based control policy in 2022, the system has disseminated 158,440 messages related to blossom control and symptom prediction to farmers and professional managers in its inaugural year. Furthermore, the system has been refined to include control messages that account for the mechanism of action of pesticides distributed to farmers in specific counties, considering flower opening conditions and weather suitability for spraying. Operating as a pivotal module within the Fire Blight Forecasting Information System (FBcastS), K-Maryblyt plays a crucial role in providing essential fire blight information to farmers, professional managers, and policymakers.
17
Temple, T. N., E. C. Thompson, S. Uppala, D. Granatstein, and K. B. Johnson. "Floral Colonization Dynamics and Specificity of Aureobasidium pullulans Strains Used to Suppress Fire Blight of Pome Fruit." Plant Disease 104, no. 1 (2020): 121–28. http://dx.doi.org/10.1094/pdis-09-18-1512-re.
Full textAbstract:
Aureobasidium pullulans is used as a biocontrol agent for fire blight protection in organic apple and pear production. We assessed colonization of pome flowers by A. pullulans in orchards located near Corvallis, OR and Wenatchee, WA. Blossom Protect, a mix of A. pullulans strains CF10 and CF40, and its citrate-based companion, Buffer Protect, were sprayed at 70% bloom. Later in bloom, the population size of putative A. pullulans on flowers was estimated by dilution plating; plate scrapings of putative A. pullulans were then sampled and subjected to a PCR analysis. Sequenced PCR amplicons of the internal transcribed spacer region and the elongase gene confirmed the presence of A. pullulans, whereas a multiplex PCR with primers specific to CF10 and CF40 was used to determine the presence of the introduced strains. At Corvallis, a wet spring environment, A. pullulans, was recovered from most (>90%) Bartlett pear and Golden Delicious apple flowers sampled from experimental trees, regardless of whether the trees were treated with Blossom Protect. Nevertheless, population size estimates of A. pullulans on the flowers were correlated with the number of times Blossom Protect was sprayed on the trees. At Wenatchee, an arid spring environment, A. pullulans was detected on most flowers from trees treated with Blossom Protect, but only on a minority of flowers from nontreated controls. In both locations, the combined incidence of strains CF10 and CF40 on flowers averaged 89% on Blossom Protect–treated trees, but only 27% on adjacent, nontreated trees. During subsequent trials, the efficacy of Blossom Protect for fire blight control was compared with alternative yeast isolates, with each applied with Buffer Protect; local isolates of A. pullulans and Cryptococcus neoformans and a postharvest biocontrol strain of Cystofilobasidium infirmominiatum were used All yeast strains suppressed fire blight to a degree; however, in each of four trials, the level of suppression was highest with Blossom Protect, and it was significantly superior (P ≤ 0.05) to other yeast isolates in two of the trials. Because A. pullulans strains CF10 and CF40 were detected primarily on flowers on trees treated with Blossom Protect, and because they were detected much less frequently on nearby nontreated tress, we recommend treating every tree row with Blossom Protect at least once for organic fire blight suppression.
18
Drén, Gábor, Zoltán Szabó, János Nagy, et al. "The effect of location on the incidence of brown rot blossom and shoot blight infection on apricot." Acta Agraria Debreceniensis, no. 17 (September 14, 2005): 89–91. http://dx.doi.org/10.34101/actaagrar/17/3276.
Full textAbstract:
The aim of our study was to assess the incidence of brown rot blossom and shoot blight and caused by Monilinia laxa. Assessments of incidence were made on cv. Bergeron (susceptible to brown rot) in a flatland and a hilly growing area (at Cegléd and Gönc, respectively). In 2004, when spring and summer weather conditions were wet and cold, incidence reached 95 % for blossom blight and 33 % for shoot blight in the untreated plots. Blossom blight incidence was 1.5-2 times higher in the flatland area compared to the hilly growing area. During the blooming period of apricot, two (at flower bud stage and at full bloom) and three (at flower bud stage, at full bloom and at petal fall) fungicide applications were necessary for the successful control at Gönc and Cegléd, respectively. The difference between the two orchards was due to the fact that blooming started one week later in the hilly region (at Gönc) than in the flatland region (at Cegléd), therefore, the critical weather period coincided with blooming in the orchard in the hilly region only partially.
19
Gubler, W. Douglas, Connie J. Feliciano, Adria C. Bordas, Ed L. Civerolo, Jason A. Melvin, and Norman C. Welch. "X. fragariaeandC. cladosporioidescause strawberry blossom blight." California Agriculture 53, no. 4 (1999): 26–28. http://dx.doi.org/10.3733/ca.v053n04p26.
Full text
20
Lightner, Gary W., and Paul W. Steiner. "COMPUTERIZATION OF BLOSSOM BLIGHT PREDICTION MODEL." Acta Horticulturae, no. 273 (June 1990): 159–62. http://dx.doi.org/10.17660/actahortic.1990.273.20.
Full text
21
Reininger, Vanessa, Anita Schöneberg, and Eduard Holliger. "Fire blight plant protection efficacy trial with resistant apple cultivar ‘Ladina’." Journal of Plant Pathology 103, S1 (2021): 143–49. http://dx.doi.org/10.1007/s42161-021-00741-4.
Full textAbstract:
AbstractFire blight is a devastating disease of apple, pear and quince caused by the Gram-negative bacterium Erwinia amylovora. As antibiotics are not allowed against fire blight in Switzerland, optimization of alternative plant protection strategies is required. In this context, fire blight tolerant cultivars become of higher importance to control the disease. A plant protection product efficacy trial against fire blight with the susceptible cultivar ‘Gala Galaxy’ and the tolerant cultivar ‘Ladina’ bred at Agroscope was set up at the Agroscope Steinobstzentrum Breitenhof in 2018. Four different treatment strategies, including an untreated control, were tested on both cultivars after inoculation with Erwinia amylovora. ‘Ladina’ showed less fire blight blossom cluster infection in untreated and treated plants compared to ‘Gala Galaxy’. Blossom cluster infection rates following different plant protection treatments did not differ significantly from each other in ‘Gala Galaxy’ whereas they did in ‘Ladina’.
22
Ahn, Mun-Il, and Sung Chul Yun. "Application of the Maryblyt Model for the Infection of Fire Blight on Apple Trees at Chungju, Jecheon, and Eumsung during 2015-2020." Plant Pathology Journal 37, no. 6 (2021): 543–54. http://dx.doi.org/10.5423/ppj.oa.07.2021.0120.
Full textAbstract:
To preventively control fire blight in apple trees and determine policies regarding field monitoring, the Maryblyt ver. 7.1 model (MARYBLYT) was evaluated in the cities of Chungju, Jecheon, and Eumseong in Korea from 2015 to 2020. The number of blossom infection alerts was the highest in 2020 and the lowest in 2017 and 2018. And the common feature of MARYBLYT blossom infection risks during the flowering period was that the time of BIR-High or BIR-Infection alerts was the same regardless of location. The flowering periods of the trees required to operate the model varied according to the year and geographic location. The model predicts the risk of “Infection” during the flowering periods, and recommends the appropriate times to control blossom infection. In 2020, when flower blight was severe, the difference between the expected date of blossom blight symptoms presented by MARYBLYT and the date of actual symptom detection was only 1-3 days, implying that MARYBLYT is highly accurate. As the model was originally developed based on data obtained from the eastern region of the United States, which has a climate similar to that of Korea, this model can be used in Korea. To improve field utilization, however, the entire flowering period of multiple apple varieties needs to be considered when the model is applied. MARYBLYT is believed to be a useful tool for determining when to control and monitor apple cultivation areas that suffer from serious fire blight problems.
23
Arafat, Khaled H., Shaheen A. Hanan, and Abd-El-Aziz M. Rabab. "Antibacterial Activity of Antagonistic Bacteria and Plant Extract on Erwinia amylovora the Pathogen of Fire Blight Disease in Egypt." International Journal of Phytopathology 4, no. 2 (2015): 73–79. http://dx.doi.org/10.33687/phytopath.004.02.1187.
Full textAbstract:
The blossom blight phase of fire blight disease on pear trees, caused by the bacterium Erwinia amylovora (Burrill), was typically managed by applying the antibiotic, streptomycin sulfate and copper, to trees during blossom. Biological control agents of fire blight can be achieved by applying nonpathogenic bacteria, viz. Bacillus subtilis or Pantoea agglomerans and plant extract, viz. Harmel (Peganum harmala L.) during open flowers as spraying treatments. The objective of this study was to examine the alternative bactericides against bacterium E. amylovora in vitro and in vivo during two seasons (2013-2014) in Al-Gharbia governorate, Egypt. Our results revealed the ability of these antagonistic bacteria and plant extract can decreased fire blight severity on pear trees. Further studies at different locations in Egypt with large scale application would allow us to make stronger recommendations including their ability to prevent disease and used them as main component in integrated pest management program.
24
Dewdney, M. M., A. R. Biggs, and W. W. Turechek. "A Statistical Comparison of the Blossom Blight Forecasts of MARYBLYT and Cougarblight with Receiver Operating Characteristic Curve Analysis." Phytopathology® 97, no. 9 (2007): 1164–76. http://dx.doi.org/10.1094/phyto-97-9-1164.
Full textAbstract:
Blossom blight forecasting is an important aspect of fire blight, caused by Erwinia amylovora, management for both apple and pear. A comparison of the forecast accuracy of two common fire blight forecasters, MARYBLYT and Cougarblight, was performed with receiver operating characteristic (ROC) curve analysis and 243 data sets. The rain threshold of Cougarblight was analyzed as a separate model termed Cougarblight and rain. Data were used as a whole and then grouped into geographic regions and cultivar susceptibilities. Frequency distributions of cases and controls, orchards or regions (depending on the data set), with and without observed disease, respectively, in all data sets overlapped. MARYBLYT, Cougarblight, and Cougarblight and rain all predicted blossom blight infection better than chance (P = 0.05). It was found that the blossom blight forecasters performed equivalently in the geographic regions of the east and west coasts of North America and moderately susceptible cultivars based on the 95% confidence intervals and pairwise contrasts of the area under the ROC curve. Significant differences (P < 0.05) between the forecasts of Cougarblight and MARYBLYT were found with pairwise contrasts in the England and very susceptible cultivar data sets. Youden's index was used to determine the optimal cutpoint of both forecasters. The greatest sensitivity and specificity for MARYBLYT coincided with the use of the highest risk threshold for predictions of infection; with Cougarblight, there was no clear single risk threshold across all data sets.
25
Bell, Richard L., T. van der Zwet, and R. C. Blake. "060 `Blake's Pride' Fire Blight-resistant Pear Cultivar." HortScience 34, no. 3 (1999): 451D—451. http://dx.doi.org/10.21273/hortsci.34.3.451d.
Full textAbstract:
`Blake's Pride' has been released jointly by USDA and The Ohio State Univ. as a new fire blight-resistant cultivar. The original seedling tree was selected in 1977 at the Ohio Agricultural Research and Development Center in Wooster by R.C. Blake and T. van der Zwet from a cross of US 446 × US 505, performed in 1965 by H.J. Brooks, and was tested under the original seedling number, OHUS 66131-021. The fruit of `Blake's Pride' is pyriform to round-pyriform in shape, and is moderate in size, averaging ≈2.75″ to 3″ in diameter, and 3.25″ in height. The stem is short, medium in thickness, and upright. Skin undercolor is yellow, the finish is glossy, and 20% to 30% of the fruit surface is covered with a smooth, light tan russet. Harvest maturity occurs about 3 weeks after `Bartlett', and the fruit will store in air storage for at least 3 months without core breakdown or superficial scald. The flesh texture is moderately fine, juicy, and buttery. Grit cells are moderately small and occur primarily around the core and in a thin layer under the skin, similar to `Bartlett'. The flavor is subacid and aromatic. The tree is moderate in vigor on `Bartlett' seedling rootstock, and upright-spreading in habit. Yield has been moderate to moderately high. Fire blight infections are rare, and extend no further than 1-year-old growth. Artificial blossom inoculations indicate a moderate degree of resistance of blossoms to fire blight infection. Resistance of `Blake's Pride' to both shoot and blossom infection is much greater than that of `Bartlett'.
26
Sundin, George W., Nicole A. Werner, Keith S. Yoder, and Herb S. Aldwinckle. "Field Evaluation of Biological Control of Fire Blight in the Eastern United States." Plant Disease 93, no. 4 (2009): 386–94. http://dx.doi.org/10.1094/pdis-93-4-0386.
Full textAbstract:
The bacterial antagonists Pseudomonas fluorescens A506, Pantoea agglomerans C9-1, and Pantoea agglomerans E325 and preparations of Bacillus subtilis QST 713 containing bacterial endospores and lipopeptide metabolites were evaluated for efficacy in controlling fire blight in Michigan, New York, and Virginia. When examined individually, the biological control materials were not consistently effective in reducing blossom infection. The average reduction in blossom infection observed in experiments conducted between 2001 and 2007 was variable and ranged from 9.1 to 36.1%, while control with streptomycin was consistent and ranged from 59.0 to 67.3%. Incidence of blossom colonization by the bacterial antagonists was inconsistent, and <60% of stigmata had the antagonists present in 12 of 25 experiments. Consistent control of blossom infection was observed when the biological control materials were integrated into programs with streptomycin, resulting in a reduction of the number of streptomycin applications needed to yield similar levels of control. Our results indicate that the prospects for biological control of fire blight in the eastern United States are currently not high due to the variability in efficacy of existing biological control options.
27
Choi, Hyo-Won, Woohyung Lee, Mun-Il Ahn, et al. "Specific Weather Factors Affecting the Incidence of Fire Blight in Korea from 2020 to 2023." Research in Plant Disease 30, no. 3 (2024): 300–303. http://dx.doi.org/10.5423/rpd.2024.30.3.300.
Full textAbstract:
Since its initial outbreak in Korea in 2015, fire blight has consistently emerged annually. Fire blight outbreaks usually begin in May, peak in June, and decline in July in Korea. In this study, we analyzed cases that exhibit a distinct pattern of disease occurrence based on yearly weather conditions from 2020 to 2023. In 2020, fire bight disease occurrence began in late May. Although the disease incidence started late by the low temperatures in April, which caused flowering period delayed, the incidence increased significantly due to the high risk of blossom infection. In 2021, the first outbreak began in late April because the flower infection started in early April. In 2022, despite the high blossom infection risk during the flowering period in April and the high incidence of fire blight in May, the incidence decreased sharply from June due to the low rainfall in May. In 2023, due to torrential rains and hail in late June, the incidence of fire blight increased even in July. Considering the weather factors that affect the increase of fire blight disease, it is suggested that control measures to prevent the fire blight infection should be carried out before and after wind-driven rains.
28
Sidhu, O. P. "Blossom Blight of Guayule Caused byAlternaria infectoria." Plant Disease 75, no. 7 (1991): 748. http://dx.doi.org/10.1094/pd-75-0748.
Full text
29
Watson, W. A., E. I. Zehr, and L. W. Grimes. "Influence of Temperature and Wetting Period on Inoculum Production by Monilinia fructicola in Peach Twig Cankers." Plant Disease 86, no. 6 (2002): 666–68. http://dx.doi.org/10.1094/pdis.2002.86.6.666.
Full textAbstract:
Overwintering cankers in peach twigs caused by the brown rot fungus, Monilinia fructicola, were studied to identify the relationships of wetting period and temperature on sporulation. Sporulation was observed on blighted blossoms, peduncles, abscission scars, and cankers resulting from contact with infected fruits. The frequency of sporulation on overwintered infected tissues was greater at 15 and 23°C than at 4 or 11°C. Twelve hours of wetting was sufficient at all temperatures studied (5 to 23°C) for sporulation to occur, but the number of twig cankers supporting sporulation increased with time of wetting up to 72 h. Given the additional moisture requirements for spore germination, ingress, and infection, 17 to 30 h of wetting or high humidity during bloom may be needed for blossom blight to occur unless viable conidia are already present as a result of previous wetting periods.
30
Komar-Tyomnaya, L. D. "Adaptability of early flowering ornamental peach cultivars." Pomiculture and small fruits culture in Russia 74 (October 19, 2023): 32–41. http://dx.doi.org/10.31676/2073-4948-2023-74-32-42.
Full textAbstract:
To assess the adaptive potential of very early, early and early-medium flowering cultivars of ornamental peach, their frost resistance taking into account the rate of microsporogenesis, susceptibility to blossom blight, leaf curl and powdery mildew were assessed in connection with their use in breeding and landscaping. According to the results of freezing, it was revealed that the early-middle flowering cultivars subgroup showed greater frost resistance. When exposed to -16 °C in February, the number of live buds in different cultivars varied from 0 to 42 % in 2020 and from 13.64 to 95.65 % in 2021, because they were at later stages of development. The temperature of -10°C in March 2020 had a significant detrimental effect on the opened buds and blossoming buds of most genotypes. The maximum percentage of live buds (48.08-64.21 %) was noted in cultivars at the stage of the appearance of sepals. Frost -3°C at the end of March 2019 before flowering was weak: the number of live buds varied between 79.22-100 % in many cultivars. Three early-flowering cultivars with the highest frost resistance of generative buds (Lel, Frezi Grant and Ruthenia) were identified during February freezing and 3 cultivars (Lel, Miraisikl 2/4 and Ruthenia) during March freezing. Their use in regions with similar frosts in the late winter and early spring periods does not significantly reduce the ornamental value of plants. An assessment of susceptibility to the main fungal diseases showed that early-flowering cultivars are most sensitive to the causative agent of blossom blight. The cultivar Snezhnaya Koroleva showed the least susceptibility to the three studied pathogens, to two pathogens – Lel, Zhisele (to blossom blight and leaf curl) and Lyubava (to blossom blight and powdery mildew). This allows them to be more widely used in landscaping and, depending on breeding tasks, to be used in breeding as sources of tolerance.
31
Pusey, P. L., and T. J. Smith. "Relation of Apple Flower Age to Infection of Hypanthium by Erwinia amylovora." Plant Disease 92, no. 1 (2008): 137–42. http://dx.doi.org/10.1094/pdis-92-1-0137.
Full textAbstract:
Blossom age as related to hypanthial susceptibility to Erwinia amylovora is not well established, but is relevant to disease risk assessment. To test this, detached crab apple blossoms were maintained for various periods and at different temperatures before applying inoculum to hypanthia. Inoculum potential on hypanthia due to wetting was evaluated by subjecting detached stigma-inoculated blossoms (~106 CFU per flower) to varying amounts and durations of simulated rain (or dew) at 14°C. Blossoms of varying age on mature ‘Gala’ apple trees were inoculated on hypanthia with 102, 104, or 106 CFU per flower. In the laboratory, susceptibility decreased with flower age at rates that increased with temperature. Wetness periods up to 12 h resulted in populations on hypanthia of <103 CFU per flower; 24 h of wetness resulted in ~104 or ~105 CFU. A dose response was shown in the orchard, and regression curves indicated steepest decline of susceptibility during initial days after petal expansion. Disease models incorporating a blossom-age component may be effective because they indicate the potential for infection when temperatures favor rapid bacterial growth on stigmas within a window of high hypanthial susceptibility. Further investigation of these relationships could lead to advancements in determining fire blight risk.
32
Marinova-Todorova, Mariela, Jukka Ranta, and Salla Hannunen. "The suitability of Finnish climate for fire blight (Erwinia amylovora) epidemics on apple." Agricultural and Food Science 24, no. 1 (2015): 59–66. http://dx.doi.org/10.23986/afsci.48472.
Full textAbstract:
Fire blight, which is an important disease of apples and pears, has never been detected in continental Finland. In this study the suitability of the Finnish climate for apple blossom blight infections by Erwinia amylovora was evaluated with the epidemiological model MaryblytTM. This was done in fourteen locations, and for two apple cultivars differing in flowering times. Climatic conditions were predicted to be suitable for blossom infections in 18 - 51% of the years, and the annual period of suitable conditions was predicted to last up to two to five days, depending on the location and apple cultivar. The suitable period was predicted to be longer in some locations in central Finland than in those in the southernmost parts of the country. Based on these results the official surveys that are carried out to confirm the absence of fire blight in Finland cannot be targeted only to some parts of the country.
33
Schnyder, Anya, Leo Eberl, and Kirsty Agnoli. "Investigating the Biocontrol Potential of the Natural Microbiota of the Apple Blossom." Microorganisms 10, no. 12 (2022): 2480. http://dx.doi.org/10.3390/microorganisms10122480.
Full textAbstract:
Erwinia amylovora, the causative agent of fire blight, leads to important economic losses of apple and pear crops worldwide. This study aimed to investigate the potential of the resident microbiota of the apple blossom in combatting plant disease-causing organisms, with a focus on controlling fire blight. We obtained 538 isolates from sites around Canton Zurich, which we tested for activity against Pectobacterium carotovorum and E. amylovora. We also evaluated the isolates’ activity against oomycete and fungal pathogens. Nine isolates showed activity against P. carotovorum, and eight of these against E. amylovora. Furthermore, 117 showed antifungal, and 161 anti-oomycete, activity. We assigned genera and in some cases species to 238 of the isolates by sequencing their 16S RNA-encoding gene. Five strains showed activity against all pathogens and were tested in a detached apple model for anti-E. amylovora activity. Of these five strains, two were able to antagonize E. amylovora, namely Bacillus velezensis #124 and Pantoea agglomerans #378. We sequenced the P. agglomerans #378 genome and analyzed it for secondary metabolite clusters using antiSMASH, revealing the presence of a putative bacteriocin cluster. We also showed that B. velezensis #124 exhibits strong activity against three different fungi and two oomycetes in vitro, suggesting a broader capacity for biocontrol. Our results showcase the protective potential of the natural apple blossom microbiota. We isolated two candidate biocontrol strains from apple blossoms, suggesting that they might persist at the most common entry point for the causative agent of fire blight. Furthermore, they are probably already part of the human diet, suggesting they might be safe for consumption, and thus are promising candidates for biocontrol applications.
34
Gubler, W. D., A. J. Feliciano, A. C. Bordas, E. C. Civerolo, J. A. Melvin, and N. C. Welch. "First Report of Blossom Blight of Strawberry Caused by Xanthomonas fragariae and Cladosporium cladosporioides in California." Plant Disease 83, no. 4 (1999): 400. http://dx.doi.org/10.1094/pdis.1999.83.4.400a.
Full textAbstract:
In the spring of 1996, severe blossom blight occurred in some strawberry fruit production fields in the Watsonville area. The symptoms, in addition to blighting of entire flowers, were as follows: on the lower surface of the calyx, watersoaked lesions that appeared dark green under reflected light and translucent under transmitted light; necrotic calyces of seemingly healthy green and ripe fruits; watersoaking of the base of the calyx that extended into the pedicel; green-gray sporulation on dead anthers; and presence of flower clusters with small and irregularly shaped fruits. Yellow bacterial colonies were consistently isolated from water-soaked and necrotic lesions on calyces and pedicels. These colonies were entire, circular, raised, glistening, mucoid, and slow growing, characteristics typical of Xanthomonas fragariae on nutrient agar-glucose-yeast extract medium. The bacterial isolate was also identified by rep-polymerase chain reaction as X. fragariae. In addition to the yellow bacteria, a fungus was also frequently isolated from infected anthers, sepals, petals, and pistils, and was identified as Cladosporium cladosporioides. On potato dextrose agar, the fungus had velvetlike colonies colored olivaceous-green to olivaceous-brown, apically and laterally branched conidiophores, and lemon-shaped conidia that were usually smooth but sometimes textured. Blossoms of greenhouse-grown strawberry plants cv. Selva were inoculated with either or both organisms. Blossoms inoculated with X. fragariae developed symptoms distinct from those inoculated with C. cladosporioides. The most prominent visible symptoms caused by X. fragariae were watersoaked lesions on calyces that later became necrotic, watersoaking of the calyx that extended into the pedicel, and blighting of flowers and developing fruits as a result of girdling of the pedicel. Infection by C. cladosporioides was characterized by necrosis of flower parts or the entire flower, presence of green-gray sporulation on dead anthers, and production of small and malformed or misshapen fruits. Inoculation with both organisms produced all the symptoms described above in different flowers of a plant. Infection with both organisms aggravated disease severity, but each organism was capable of inducing blossom blight independently. Both organisms were reisolated from artificially inoculated strawberry flowers, fulfilling Koch's postulate for proof of pathogenicity. This is the first report of the two organisms causing blossom blight of strawberry in California. This is also the first report that C. cladosporioides is a pathogen of strawberry.
35
Stockwell, V. O., K. B. Johnson, and J. E. Loper. "Establishment of Bacterial Antagonists of Erwinia amylovora on Pear and Apple Blossoms as Influenced by Inoculum Preparation." Phytopathology® 88, no. 6 (1998): 506–13. http://dx.doi.org/10.1094/phyto.1998.88.6.506.
Full textAbstract:
The influence of inoculum preparation on the establishment of bacterial antagonists that suppress fire blight and Erwinia amylovora on blossoms was evaluated. Aqueous suspensions of Pseudomonas fluorescens A506, E. herbicola C9-1R, or E. amylovora 153N were prepared from cells harvested from the surface of an agar medium or from cells that were lyophilized after culture under similar conditions. Bacterial suspensions (1 × 108 CFU/ml) were sprayed on pear and apple trees at 50% bloom near midday. The incidence of recovery (proportion of blossoms containing detectable populations) and the population sizes of the bacteria on individual blossoms with detectable populations were followed over a period of several days. Fluorescent microspheres (1 μm in diameter) were added to sprays at a concentration of 1 × 107 microspheres per ml to mark blossoms that were open during application of bacteria. After dilution-plating, the stigmas and styles of each blossom were examined for the presence of microspheres with an epifluorescence microscope. In three of five trials, bacteria applied as suspensions of lyophilized cells were recovered from a greater proportion of blossoms than bacterial cells harvested directly from culture media. Every blossom harvested within 6 days after spraying had microspheres present on the surfaces of the styles and stigmas; thus, lack of establishment of detectable populations, rather than escape of blossoms from spray inoculation, accounted for the differences in proportion of blossoms colonized by the different preparations of bacteria. The use of lyophilized cells in field trials decreased variability in the establishment of bacteria on blossoms.
36
Paulin, J. P., R. Chartier, and J. M. Boré. "BLOSSOM SUSCEPTIBILITY TO FIRE BLIGHT OF CIDER APPLE." Acta Horticulturae, no. 338 (August 1993): 427–30. http://dx.doi.org/10.17660/actahortic.1993.338.71.
Full text
37
Follas, G., and H. M. Beetz. "Control of blossom blight in stonefruit with difenoconazole." Proceedings of the New Zealand Weed and Pest Control Conference 44 (January 8, 1991): 262–64. http://dx.doi.org/10.30843/nzpp.1991.44.10823.
Full text
38
EVERETT, K. R., and W. R. HENSHALL. "Epidemiology and population ecology of kiwifruit blossom blight." Plant Pathology 43, no. 5 (1994): 824–30. http://dx.doi.org/10.1111/j.1365-3059.1994.tb01627.x.
Full text
39
MIYOSHI, Takanori, Akio NIBE, and Yasunobu TACHIBANA. "Epidemiological Studies on Bacterial Blossom Blight of Kiwifruit. 4. Relationship between Disease Incidence of Bacterial Blossom Blight and Meteorological Factors." Japanese Journal of Phytopathology 62, no. 5 (1996): 533–36. http://dx.doi.org/10.3186/jjphytopath.62.533.
Full text
40
Norelli, J. L., H. T. Holleran, W. C. Johnson, T. L. Robinson, and H. S. Aldwinckle. "Resistance of Geneva and Other Apple Rootstocks to Erwinia amylovora." Plant Disease 87, no. 1 (2003): 26–32. http://dx.doi.org/10.1094/pdis.2003.87.1.26.
Full textAbstract:
When vigorously growing shoots of 49 different apple rootstocks grown in a greenhouse were inoculated with different strains of Erwinia amylovora, Budagovsky 9 (B.9), Ottawa 3, Malling 9, and Malling 26 were the most fire blight susceptible rootstocks and Geneva 11, Geneva 65, Geneva 16, Geneva 30, Pillnitzer Au51-11, Malling 7, and several breeding selections were the most resistant. Significant strain—rootstock interactions were observed in the amount of fire blight that resulted from inoculation. Field-grown fruiting ‘Royal Gala’ trees on Geneva 16 and Geneva 30 rootstocks were highly resistant to rootstock infection (no tree mortality) when trees sustained severe blossom infection with E. amylovora, compared with Malling 9 and Malling 26 rootstock clones, which were highly susceptible to infection (36 to 100% tree mortality). In contrast to potted own-rooted B.9 plants inoculated in a greenhouse, B.9 rootstocks of orchard trees appeared resistant to rootstock infection (0% tree mortality). Orchard trees on Geneva 11 were moderately resistant to rootstock infection (25% tree mortality). There was general agreement in the evaluation of resistance under orchard conditions when rootstock resistance was evaluated in relation to controlled blossom inoculation or to natural blossom infection.
41
Hussain, Tanveer, Faheem Ahmed Khan, and Rawish Ahmed Sikander. "Assessment of mycotic diseases attack on indigenous old mango plants grown in Vatala park, Tehsil Bernala District Bhimber, Azad Kashmir." Natural Resources Conservation and Research 6, no. 2 (2024): 2985. http://dx.doi.org/10.24294/nrcr.v6i2.2985.
Full textAbstract:
The current research work was explored fungal attacks on different parts of mango (Mangifera indica L.) trees naturally grown in Tehsil Bernala, District Bhimber Azad Kashmir. Different symptoms were observed, like stem end rot, anthracnose dieback, and blossom blight, during field survey. The identification of mycotic diseases was confirmed by further direct microscopic examination of affected parts of mango trees. Then fungal diseases of mango trees were isolated by microculture and purification methods on different media. Some other parameters, like disease incidence and disease severity rates, were measured against each identified disease through a pathogenicity test under in vitro conditions. It was indicated that maximum disease incidence (DI) was 33.73% measured against dieback disease. The lowest incidence (30.98%) was measured against blossom blight disease. It was also found that disease severity (DS) was rated from 0 to 4 on a visual rating scale.
42
Esterio, Marcela, Claudio Osorio-Navarro, Claudia Carreras, et al. "Botrytis prunorum Associated to Vitis vinifera Blossom Blight in Chile." Plant Disease 104, no. 9 (2020): 2324–29. http://dx.doi.org/10.1094/pdis-09-19-2055-sc.
Full textAbstract:
Table grapes are highly susceptible to Botrytis cinerea infections during the bloom period. After reaching the flower development stage, B. cinerea remains quiescent until berry ripening or gives rise to blossom blight under specific climate conditions. A research study was conducted on the Chilean Central Valley during the 2018–2019 growing season. Flowers of Vitis vinifera cv. Thompson Seedless were collected and B. cinerea was isolated together to a second and morphologically different species, characterized by white mycelium and low to no sporulation (11.4% of total isolates). Three randomly selected isolates within this population were genetically examined and identified as Botrytis prunorum based on a phylogenetic multilocus approach using partial regions of genes RPB2, HSP60, and G3PDH or NEP1 and NEP2. Pathogenicity tests showed that B. prunorum infects and causes wilting in healthy table grape flowers. B. prunorum isolates were able to infect Thompson Seedless berries, inducing lesions between 13.11 and 41.53% with respect to the lesion diameter generated by B. cinerea B05.10. The fungicide sensitivity was evaluated. The three genetically characterized isolates were sensitive to boscalid and to cyprodinil/fludioxonil mixture with a mean EC50 value of 5.5 µg/ml and 0.065 µg/ml, respectively. However, loss of sensitivity to fenhexamid was determined, with a mean EC50 value of 5.13 µg/ml. Our understanding about blossom blight in V. vinifera has been limited to B. cinerea. Here we associated B. prunorum as a second causal agent of this disease in Chile. This data represents a first approach to the epidemiological characteristics of B. prunorum associated with blossom blight in table grapes.
43
Smith, Barbara J. "Botrytis Blossom Blight of Southern Blueberries: Cultivar Susceptibility and Effect of Chemical Treatments." Plant Disease 82, no. 8 (1998): 924–27. http://dx.doi.org/10.1094/pdis.1998.82.8.924.
Full textAbstract:
The susceptibility of blueberry flowers at each developmental stage was evaluated by inoculating potted blueberry bushes of the rabbiteye cultivars Climax, Premier, and Tifblue, and the southern highbush cultivars Gulfcoast and Cooper, during bloom with a conidial suspension of Botrytis cinerea and incubating in a dew chamber for 2 days at 20°C and 100% relative humidity. Flower stage was rated at the beginning of each study and at 2 and 4 weeks after inoculation. The efficacy of five fungicides (benomyl, captan, cyprodinil, cyprodinil + CGA173506, and propiconazole) and a surfactant for control of Botrytis blossom blight was evaluated by inoculating Climax and Gulfcoast plants 2 days before or 2 days after treatment with each fungicide. The effect of chemicals used during bloom on the severity of Botrytis blossom blight was evaluated by treating Tifblue and Cooper plants with gibberellic acid, surfactant, and fungicide combinations 1 day prior to inoculation. Botrytis disease symptoms were scored 2 and 4 weeks after inoculation on a visual scale of 0 to 7. Flower susceptibility increased as flower stage at inoculation increased. Tifblue flowers at or near full bloom (stages 5 and 6) at the time of inoculation were very susceptible to Botrytis blossom blight. Flowers treated with benomyl, cyprodinil, and cyprodinil + CGA173506 2 days after inoculation had lower Botrytis severity scores than inoculated flowers not treated with fungicides. Flowers treated with gibberellic acid 1 day prior to inoculation had lower Botrytis scores 2 and 4 weeks later than untreated flowers, while flowers treated with a nonionic surfactant received the same Botrytis severity scores as untreated flowers.
44
Stockwell, V. O., K. B. Johnson, D. Sugar, and J. E. Loper. "Antibiosis Contributes to Biological Control of Fire Blight by Pantoea agglomerans Strain Eh252 in Orchards." Phytopathology® 92, no. 11 (2002): 1202–9. http://dx.doi.org/10.1094/phyto.2002.92.11.1202.
Full textAbstract:
Fire blight, caused by Erwinia amylovora, is the most serious bacterial disease of pear and apple trees. Biological control with strains of Pantoea agglomerans (syn. Erwinia herbicola) may provide an effective disease management strategy for fire blight. Most strains of P. agglomerans evaluated for suppression of fire blight produce compounds that inhibit the growth of E. amylovora in culture. The role of these inhibitory compounds in fire blight suppression in orchard environments has not been studied. In seven field trials in Oregon, we compared the population dynamics and disease suppression with P. agglomerans Eh252, a strain that produces a single antibiotic, with its near-isogenic antibiotic-deficient derivative, strain 10:12. Water or suspensions of Eh252 or 10:12 (1 × 108 CFU/ml) were applied at 30 and 70% bloom to pear or apple trees. Aqueous suspensions of freeze-dried cells of E. amylovora (3 × 105 CFU/ml) were applied at full bloom. Additional trees were treated with streptomycin or oxytetracycline at 30 and 70% bloom and in some experiments, 1 day after application of the pathogen. Population sizes of Eh252 or 10:12 on pear blossoms were estimated by spreading dilutions of blossom washes on culture media. Average population sizes of Eh252 and 10:12 on blossoms ranged from 105 to 107 CFU, and in five of six trials, the relative area under the population curve of Eh252 was not significantly different than that of its derivative 10:12. Both Eh252 and 10:12 reduced the growth of the pathogen on blossoms compared with inoculated water-treated controls. Eh252 significantly decreased the incidence of fire blight in six of seven field trials compared with the incidence on water-treated trees, and 10:12 similarly reduced the incidence of fire blight in four of seven trials. In three of seven field trials, trees treated with Eh252 had a significantly lower incidence of fire blight compared with trees treated 3 with 10:12. Overall,3 Eh252 reduced the incidence of fire blight by 55 ± 8%, 10:12 by 30 ± 6%, streptomycin by 75 ± 4%, and oxytetracycline by 16 ± 14%. The effectiveness of strain 10:12 compared with water treatment indicates that other mechanisms (e.g., competitive exclusion or habitat modification) also contribute to disease suppression by P. agglomerans. The increased suppression of fire blight by the parental strain Eh252 compared with the antibiotic-deficient mutant 10:12 indicates that antibiosis is an important mechanism of biological control of fire blight.
45
Ngugi, Henry K., and James R. Schupp. "Evaluation of the Risk of Spreading Fire Blight in Apple Orchards with a Mechanical String Blossom Thinner." HortScience 44, no. 3 (2009): 862–65. http://dx.doi.org/10.21273/hortsci.44.3.862.
Full textAbstract:
The risk of spreading fire blight in apples after mechanical thinning with a rotating string blossom thinner was evaluated in field and potted-tree experiments. In the field experiment, using the mechanical thinner on noninoculated trees immediately after operating the equipment on inoculated trees significantly (P < 0.01) increased fire blight incidence resulting in 90 ± 20.01 (mean ± SE) infected shoots compared with 23.5 ± 8.97 diseased shoots in similar trees that were not thinned mechanically. A similar result was obtained in greenhouse experiments whereby healthy apple plants positioned adjacent to diseased plants before the group was subjected to the mechanical thinner developed more than twice the number of infected shoots as that on similar plants that were not thinned. These results indicate that under conditions conducive to infection, the mechanical blossom thinner significantly increases the risk of spreading Erwinia amylovora. The use of the thinner should therefore be limited to orchards with no history of disease in the last 3 years and on days when predicted weather is not suitable for tree infection by E. amylovora; otherwise, a severe fire blight epidemic could develop in the orchard.
46
Lee, Young-Sun, Hyo-Shim Han, Gyoung-Hee Kim, Young-Jin Koh, Jae-Seoun Hur, and Jae-Sung Jung. "Causal Agents of Blossom Blight of Kiwifruit in Korea." Plant Pathology Journal 25, no. 3 (2009): 220–24. http://dx.doi.org/10.5423/ppj.2009.25.3.220.
Full text
47
Gawith, R. S., and K. G. Tate. "Fungicide evaluation for control of blossom blight of nectarines." Proceedings of the New Zealand Weed and Pest Control Conference 42 (January 8, 1989): 170–73. http://dx.doi.org/10.30843/nzpp.1989.42.10983.
Full text
48
Pennycook, S. R., and C. M. Triggs. "BACTERIAL BLOSSOM BLIGHT OF KIWIFRUIT-A 5-YEAR SURVEY." Acta Horticulturae, no. 297 (April 1992): 559–66. http://dx.doi.org/10.17660/actahortic.1992.297.73.
Full text
49
MUKOBATA, Hiroyuki, Takahito SUZUI, Kiyonobu NAHATA, and Takashi YAMAMOTO. "Tulip blossom blight caused by Phytophthora cactorum in Japan." Japanese Journal of Phytopathology 53, no. 3 (1987): 291–300. http://dx.doi.org/10.3186/jjphytopath.53.291.
Full text
50
MIYOSHI, Takanori, and Yasunobu TACHIBANA. "Epidemiological Studies on Bacterial Blossom Blight of Kiwifruit. 2. Relationship between Occurrence of Bacterial Blossom Blight and the Rate of Bud Development." Japanese Journal of Phytopathology 62, no. 5 (1996): 523–27. http://dx.doi.org/10.3186/jjphytopath.62.523.
Full text