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1
Croker, KP, und MA Johns. „Reproductive performance of ewes fed sweet narrow-leafed lupin seed infected with Phomopsis leptostromiformis“. Australian Journal of Experimental Agriculture 25, Nr. 3 (1985): 536. http://dx.doi.org/10.1071/ea9850536.
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An experiment was designed to examine the reproductive performance of Merino ewes fed sweet narrow-leafed lupin seed infected with Phomopsis leptostromiformis and containing small quantities of the toxin phomopsin. Two groups of mature ewes were supplemented with lupin seed with either a low (2%) or a high (21%) level of Phomopsis infection at a rate equivalent to 500 g/sheep.day for a period from 14 days before the start of joining until day 17 of joining. A third group received no supplement. The percentages of lambing ewes with multiple births were marginally increased (P<0.10) in the supplemented ewes (14.3, 27.5 and 26.2% for the unsupplemented and the 2 and 21% Phomopsis infected seed groups, respectively) while the percentages of lambs born were 99.0, 93.6 and 112.8% for the unsupplemented and the 2 and 21 % Phomopsis-infected seed groups, respectively. Supplementation of ewes with lupin seed containing a relatively high level of Phomopsis (21%), but a low quantity of phomopsin, did not depress reproductive performance.
2
Książkiewicz, M., K. Wójcik, W. Irzykowski, W. Bielski, S. Rychel, J. Kaczmarek, P. Plewiński, E. Rudy und M. Jędryczka. „Validation of Diaporthe toxica resistance markers in European Lupinus angustifolius germplasm and identification of novel resistance donors for marker-assisted selection“. Journal of Applied Genetics 61, Nr. 1 (22.10.2019): 1–12. http://dx.doi.org/10.1007/s13353-019-00521-y.
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Abstract The fungus, Diaporthe toxica, anamorph Phomopsis sp., previously classified as P. leptostromiformis, is a plant endophyte and occasional pathogen, causing Phomopsis stem blight. This disease is damaging not only to lupins but also to the animals grazing on infected plants, due to the toxic secondary metabolites called phomopsins. The aim of this work was to validate markers for resistance to Phomopsis stem blight in narrow-leafed lupins and identify novel germplasm with increased levels of resistance to the disease. Plant inoculations were performed using ten isolates of D. toxica, originating from Australia and Poland. The European core collection of L. angustifolius was evaluated both in a controlled environment and with field experiments to classify the accessions based on their resistance to the disease. Simultaneously, the accessions were assayed with disease resistance markers to identify donors of hypothetical resistance alleles. We have found that the European lupin germplasm collection preserves wild and domesticated donors of at least two resistance genes to Phomopsis stem blight, including Phr1 and PhtjR. Molecular markers PhtjM7, InDel2, and InDel10, tagging PhtjR gene, were applicable for marker-assisted selection targeting the European gene pool with an expected accuracy of 95%. None of diagnostic markers for the Phr1 locus was found useful for European breeding programs; two existing markers Ph258M1 and Ph258M2 were unreliable, due to a high percentage of false-positive results (up to 58%) and a high recombination rate between markers (~ 30%).
3
Wood, PM, DS Petterson, GR Hancock und GA Brown. „Distribution of seed infected with Phomopsis leptostromiformis and of phomopsin A within a lupin crop“. Australian Journal of Experimental Agriculture 27, Nr. 1 (1987): 77. http://dx.doi.org/10.1071/ea9870077.
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A detailed study was made of the Phomopsis leptostromiformis infection and phomopsin A content of seed within a lupin crop having a high level of visible pod infection. Over 96% of the visibly infected seeds contained viable P. leptostromlformis. Visually clean, or whole white seed, from the primary pods had a higher level of fungal infection (56%) than comparable seed from the other pods (11%). The discoloured seed content of the primary pods was higher than for the other pods in each instance. The phomopsin A content of the seed was higher than previously reported. Although the cracked and discoloured seed fractions contained from 200 to 2300 �g of phomopsin A/kg, the highest amount of this toxin detected in whole white seed was 6 �g/kg.
4
Tuset, J. J., und M. A. T. Portilla. „Taxonomic status of Fusicoccum amygdali and Phomopsis amygdalina“. Canadian Journal of Botany 67, Nr. 5 (01.05.1989): 1275–80. http://dx.doi.org/10.1139/b89-168.
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A comparative study was done in Spain of canker and withering of branches in almond and peach trees. Similar diseases of these fruit trees, described by several authors and attributed to Fusicoccum amygdali and Phomopsis amygdalina, suggests that these fungi are identical. Spanish isolates produced phialidic conidiogenous cells and occasionally β-conidia typical of the genus Phomopsis. A study of the type specimen of F. amygdali reveals that it also belongs in Phomopsis. Phomopsis amygdali (Del.) Tuset & Portilla comb.nov. is proposed to accommodate the fungus; Phomopsis amygdalina Canonaco is reduced to synonymy with it.
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Petterson, DS, JE Peterson, LW Smith, PM Wood und CCJ Culvenor. „Bioassay of the contamination of lupin seed by the mycotoxin phomopsin“. Australian Journal of Experimental Agriculture 25, Nr. 2 (1985): 434. http://dx.doi.org/10.1071/ea9850434.
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Samples of seed from commercial crops of Lupinus spp. in three States were tested for the presence of phomopsin, the causative agent of lupinosis. Each of 43 samples was tested in one of two laboratories using a nursling rat bioassay, and 12 of these were tested in both. Factors that could affect reproducibility of the assay were examined. There was good agreement in assessments of toxicity between laboratories. The efficiency of extraction was found to vary from about 15% at low concentrations of phomopsin to no more than 60%. Phomopsin was detected in 17 of the 43 samples, at levels ranging from < 6 �g/kg to 360 �g/kg. Phomopsis leptostromiformis infection was detected in 25 of 31 samples of seed from Western Australia, the highest infection level being 18%. The highest levels of phomopsin were found in samples with more than 8% infection.
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Vukojević, J., M. Mihaljčević und D. Franić-Mihajlović. „VARIABILITY OF Phomopsis POPULATIONS IN SUNFLOWER (Helianthus annuus L.) / VARIABILIDAD DE LAS POBLACIONES DE Phomopsis EN EL GIRASOL (Helianthus annuus L.) / VARIABILITÉ DES POPULATIONS DE Phomopsis CHEZ LE TOURNESOL (Helianthus annuus L.)“. HELIA 24, Nr. 34 (Juli 2001): 69–76. http://dx.doi.org/10.1515/helia.2001.24.34.69.
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SUMMARY Various reports state that the sunflower disease, primarily caused by Diaporthe/Phomopsis helianthi Munt.-Cvet. et al., has a wide geographic distribution in Europe, USA, Argentina and Australia. Various Phomopsis isolates obtained during this investigation of the sunflower disease differed in conidial type (α, β, α and β). Phomopsis helianthi was the only isolate producing exclusively β-conidia and perithecia on debris (Diaporthe helianthi). The other Phomopsis isolates were saprobes on sunflower plants.
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Radiastuti, Nani, Firdaus Ramadhan und Yusraini Dian Inayati Siregar3. „Antioksidan Ekstrak Kapang Endofit Phomopsis spp. dari Tanaman Kina (Cinchona calisaya)“. Jurnal Biotek Medisiana Indonesia 10, Nr. 2 (18.01.2022): 109–15. http://dx.doi.org/10.22435/jbmi.v10i2.5822.
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ABSTRACT
Phomopsis spp. is one of the endophytic fungi that was isolated from cinchona plant (Cinchona calisaya). Endophytic fungi ability to produce bioactive compounds similar to the host, as a solution to get bioactive compounds without doing a lot of exploitation in the quinine plant. This study aimed to determine the highest antioxidant activity (IC50) and known compounds acting as antioxidants in endophytic fungi extract Phomopsis spp. The extraction process was done by the maceration method by organic solvent ethyl acetate. The measured parameters IC50 and analysis of bioactive compound in extracts of endophytic fungi Phomopsis spp. The IC50 test used 1.1-diphenyl-2-picrilhidrazil (DPPH) method with UV-Vis spectrophotometry (λ 517 nm) and identification bioactive compound with Gas Chromatography-Mass Spectroscopy (GC-MS). Based on the results of the DPPH test extract of Phomopsis spp. M70 had the highest antioxidant activity with IC50 1283.95 ppm. Results of GC-MS showed hexadecanoic acid, octadecanoic acid 2-(2-hydroxyethyl) ethyl ester, benzene ethanol, 4-hydroxy-, 9-octadecanoic acid, hexadecanoic acid 2-hydroxy-1-(hydroxymethyl) ethyl ester and octadecanoic acid, 2-hydroxy-1-(hydroxymethyl) ethyl ester compounds which served as antioxidants in the extract of Phomopsis spp. M70. Extract of Phomopsis spp. M70 had the highest IC50 value but its antioxidant ability was classified as inactive.
Keywords: antioxidant, cinchona plants, endophytic fungi, Phomopsis spp.
ABSTRAK
Phomopsis spp. merupakan salah satu jamur endofit yang diisolasi dari tanaman kina (Cinchona calisaya). Kemampuan kapang endofit menghasilkan senyawa bioaktif yang mirip dengan inang, sebagai solusi mendapatkan senyawa bioaktif tanpa banyak melakukan eksploitasi pada tanaman kina. Penelitian ini bertujuan untuk mengetahui aktivitas antioksidan (IC50) tertinggi dan mengetahui senyawa yang berperan sebagai antioksidan dalam ekstrak jamur endofit Phomopsis spp. Proses ekstraksi dilakukan dengan metode maserasi dengan pelarut etil asetat. Parameter yang diukur IC50 dan analisis senyawa bioaktif dalam ekstrak jamur endofit Phomopsis spp. Uji IC50 menggunakan metode 1.1-difenil-2-picrilhidrazil (DPPH) dengan spektrofotometer UV-Vis (λ 517 nm) dan identifikasi senyawa bioaktif dengan Gas Chromatography-Mass Spectroscopy (GC-MS). Berdasarkan hasil uji DPPH ekstrak Phomopsis sp. M70 memiliki aktivitas antioksidan tertinggi dengan IC50 1283,95 ppm. Hasil GC-MS menunjukkan asam heksadekanoat, asam oktadekanoat 2- (2-hidroksietoksi) etil ester, benzenaetanol, 4-hidroksi-, asam 9-oktadekanoat, asam heksadekanoat 2-hidroksi-1- (hidroksi metil) etil ester dan asam oktadekanoat, 2 Senyawa -hidroksi-1- (hidroksimetil) etil ester yang berperan sebagai antioksidan pada ekstrak Phomopsis spp. M70. Ekstrak Phomopsis spp. M70 memiliki IC50 tertinggi namun kemampuan antioksidannya tergolong tidak aktif
Kata kunci: antioksidan, kapang endofit, Phomopsis spp., tanaman kina
8
Murali, T. S., T. S. Suryanarayanan und R. Geeta. „Endophytic Phomopsis species: host range and implications for diversity estimates“. Canadian Journal of Microbiology 52, Nr. 7 (01.07.2006): 673–80. http://dx.doi.org/10.1139/w06-020.
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Foliar endophyte assemblages of teak trees growing in dry deciduous and moist deciduous forests of Nilgiri Biosphere Reserve were compared. A species of Phomopsis dominated the endophyte assemblages of teak, irrespective of the location of the host trees. Internal transcribed spacer sequence analysis of 11 different Phomopsis isolates (ten from teak and one from Cassia fistula) showed that they fall into two groups, which are separated by a relatively long branch that is strongly supported. The results showed that this fungus is not host restricted and that it continues to survive as a saprotroph in teak leaf, possibly by exploiting senescent leaves as well as the litter. Although the endophyte assemblage of a teak tree growing about 500 km from the forests was also dominated by a Phomopsis sp., it separated into a different group based on internal transcribed spacer sequence analysis. Our results with an endophytic Phomopsis sp. reinforce the earlier conclusions reached by others for pathogenic Phomopsis sp., i.e., that this fungus is not host specific, and the species concept of Phomopsis needs to be redefined.Key words: fungal endophytes, Tectona grandis, fungal diversity, Phomopsis, host restriction.
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Li, Shuxian, Glen L. Hartman und Deborah L. Boykin. „Aggressiveness of Phomopsis longicolla and Other Phomopsis spp. on Soybean“. Plant Disease 94, Nr. 8 (August 2010): 1035–40. http://dx.doi.org/10.1094/pdis-94-8-1035.
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Phomopsis seed decay of soybean is a major cause of poor-quality soybean seed. The disease is caused primarily by the fungal pathogen Phomopsis longicolla. Aggressiveness of isolates of P. longicolla from soybean and other Phomopsis spp. from other hosts were compared by inoculating 2-week-old soybean plants of cv. Williams 82. There were significant (P ≤ 0.0001) differences among isolates based on stem length and stem lesion length. The P. longicolla soybean isolate PL16, from Mississippi, caused the shortest stem length while the non-soybean isolate P9, from Illinois, caused the greatest stem lesion length. The type isolate of P. longicolla, PL31 (Fau 600), was one of the 3 most aggressive isolates among all 48 isolates tested. The velvetleaf isolate P9 was the most aggressive among 13 isolates from non-soybean hosts. This study provided the first evaluation of aggressiveness of P. longicolla isolates from different geographic origins and the first demonstration that Phomopsis spp. isolated from cantaloupe, eggplant, and watermelon infected soybean. Knowledge about the variability of the pathogen is important for selecting isolates for breeding soybean lines with broad-based resistance to Phomopsis seed decay.
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Wrather, J. A., D. A. Sleper, W. E. Stevens, J. G. Shannon und R. F. Wilson. „Planting Date and Cultivar Effects on Soybean Yield, Seed Quality, and Phomopsis sp. Seed Infection“. Plant Disease 87, Nr. 5 (Mai 2003): 529–32. http://dx.doi.org/10.1094/pdis.2003.87.5.529.
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Incidence of Phomopsis seed decay is frequently high and quality low in seed from early-maturing maturity group III and IV soybean cultivars planted in early to mid-April in the southern United States. Cultivars resistant to this disease have not been available until the recent release of germ plasm lines SS 93-6012 and SS 93-6181. Our objective was to determine the effects of planting dates with these lines and one Phomopsis seed decay-susceptible soybean cultivar, Asgrow 3834, on seed infection by Phomopsis spp. and on yield and the correlation between percentage of Asgrow 3834 infected with Phomopsis spp. and seed quality. Generally, yields averaged over years were significantly greater for mid-April than mid-June plantings, and yields of cultivars were similar within a planting date. Soybean lines SS 93-6012 and SS 93-6181 were highly resistant to Phomopsis seed decay compared with the susceptible cultivar, Asgrow 3834. There was a significant, negative correlation between germination of seed from mid-April plantings of Asgrow 3834 and percentage of these seed infected with Phomopsis spp. Moreover, there were significant correlations between fatty acid composition of Asgrow 3834 seed and the percentage of these seed infected with Phomopsis spp. This altered composition of fatty acids may be responsible for reduced quality of oil derived from seed infected with this fungus. Phomopsis seed decay-resistant soybean lines SS 93-6012 and SS 93-6181 should be useful in breeding programs focused on developing high-yielding cultivars resistant to this disease.
11
Morcombe, PW, JG Allen, GR Hancock, RH Jacob und DL Hopkins. „Monitoring the toxicity of lupin (Lupinus angustifolius) stubbles has limited value in the prevention of lupinosis“. Australian Journal of Experimental Agriculture 32, Nr. 6 (1992): 707. http://dx.doi.org/10.1071/ea9920707.
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Lupin (Lupinus angustifolius) stubbles at 3 'sentinel' sites in the Midlands Region of Western Australia were monitored throughout the summer of 1985-86 to assess the level of infection of the stems by the fungus Phomopsis leptostromiformis, and to measure the concentration of its toxic product, phomopsin A. These parameters were found to have little value as predictors of fungal infection and of the toxicity of lupin stubbles on farms in surrounding districts. It was found also that visual rating of the level of P. leptostromiforrnis infection of lupin stems was unrelated to the concentration of phomopsin A in those stems or to the liver damage in sheep grazing stubble from which the stems were sampled. It is suggested that these ratings should not be used to advise farmers on the 'lupinosis risk' of a lupin stubble. Monitoring the phomopsin A concentration in lupin stems collected throughout a summer confirmed that rain, associated with cloudy days, was the primary environmental stimulus to a significant increase in the phomopsin A concentration.
12
Wood, PM, und DS Petterson. „Phomopsis leptostromiformis infection and phomopsin A content of lupin seed in Western Australia“. Australian Journal of Experimental Agriculture 26, Nr. 5 (1986): 583. http://dx.doi.org/10.1071/ea9860583.
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A survey of Phomopsis leptostromiformis infection of lupin seed in Western Australia was carried out in 1982 and 1983. Of the samples surveyed 39% were uninfected and 16.6% had >4% infection. These values differ significantly from a previous survey between 1976 and 1981 (49 and 8.4% respectively). There was a highly significant correlation (P <0.002) between the amount of discoloured seed and P. leptostromiformis infection. Results of toxicity tests for the mycotoxin phomopsin A, assessing hepatic injury in nursling rats, strongly implicate discoloured seeds as being the most toxic. Discoloured seed had more toxin in the seed hulls than in the kernal.
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Jayaramaiah, KM, S. Mahadevakumar, AP Charith Raj und GR Janardhana. „PCR based detection of Phomopsis vexans (Sacc. & Syd.) - The causative agent of leaf blight and fruit rot disease of Brinjal (Solanum melongena L.)“. International Journal of Life Sciences 7, Nr. 1 (05.06.2013): 17–20. http://dx.doi.org/10.3126/ijls.v7i1.8173.
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Leaf blight and fruit rot disease of brinjal (Solanum melongena) caused by the fungal pathogen Phomopsis vexans is the most prevailing diseases responsible for the significant yield loss in many Brinjal growing regions of India. The survey conducted during 2008-2010, seven (07) isolates of Phomopsis vexans causing leaf blight and fruit rot disease in different areas of Karnataka were isolated, identified and confirmed by Koch’s postulates. Identification of Phomopsis vexans by conventional culture method was time consuming and laborious. Hence, PCR based detection assay was used to detect the pathogen from DNA samples obtained from fungal isolates. Universal primer pairs designed from internal transcribed spacer regions ITS1 (5'-CGGATCTCTTGGTTCTGGCA-3') and ITS4 (5'-GACGCTCGAACAGGCATGCC-3') of the ribosomal DNA (rDNA) of the genus Phomopsis were used for PCR. The study revealed the amplification of expected 553bp PCR products in all the DNA samples isolated from different isolates of Phomopsis vexans confirming their association in leaf blight and fruit rot disease of Brinjal.DOI: http://dx.doi.org/10.3126/ijls.v7i1.8173 International Journal of Life Sciences 7(1): 2013; 17-20
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Wrather, J. A., J. G. Shannon, W. E. Stevens, D. A. Sleper und A. P. Arelli. „Soybean Cultivar and Foliar Fungicide Effects on Phomopsis sp. Seed Infection“. Plant Disease 88, Nr. 7 (Juli 2004): 721–23. http://dx.doi.org/10.1094/pdis.2004.88.7.721.
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Phomopsis seed decay (PSD) caused by Phomopsis spp. can be severe when soybean seed producers in the southern United States use the early soybean production system (ESPS) to avoid late-July through early-September drought damage to soybean. The usefulness of this production system would be greater if developing seed could be protected from PSD by foliar application of fungicides or by planting Phomopsis spp.-resistant soybean lines. The objective of this research was to determine the affects of the fungicides benomyl and azoxystrobin applied to soybean, at various times, on percent Phomopsis spp. infection of seed in Asgrow 3834, a PSD-susceptible cultivar, and SS93-6012, a PSD-resistant soybean line, planted in mid-April. The percent Phomopsis spp. infection of Asgrow 3834 seed averaged over years was significantly less for the benomyl (0.28 kg a.i. ha-1) applied at R3 + R5 treatment (48.6% seed infection) than the control (52.8% seed infection) and significantly greater for the azoxystrobin (0.17 kg a.i. ha-1) applied at R3 + R5 treatment (61.6% seed infection) than the control (52.8% seed infection). This method of managing PSD will not be acceptable to soybean growers. The percent of Phomopsis spp. infection of Asgrow 3834 seed averaged over years (52.8% seed infection) was significantly greater than for line SS93-6012 (2.8% seed infection). There were no differences in percent Phomopsis spp. infection of SS93-6012 seed between the control (2.8% seed infection) and benomyl treatment (4.0% seed infection). The most effective method for PSD management was to plant a resistant soybean line. Line SS93-6012 will be useful in breeding programs focused on developing high yielding PSD-resistant cultivars.
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Baker, Daniel M., Harry C. Minor, M. F. Brown und E. A. Brown. „Infection of immature soybean pods and seeds by Phomopsis longicolla“. Canadian Journal of Microbiology 33, Nr. 9 (01.09.1987): 797–801. http://dx.doi.org/10.1139/m87-135.
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Phomopsis longicolla Hobbs, a causal agent of Phomopsis seed decay, colonizes the seed coats and embryos of mature soybean (Glycine max (L.) Merr.) seeds. The mode of infection of immature soybean pods and seeds by P. longicolla was examined using scanning electron microscopy. Phomopsis longicolla penetrated directly through pod walls by appressoria. Penetration through stomata in the pod surface was not observed. Immature seeds were also penetrated directly. Heavily infected immature seeds showed extensive colonization of the seed coats and embryos.
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Chaukhe, AN, MJ Patil, AG Tekale und AP Deshmukh. „Effect of chemical control of phomopsis blight of brinjalcaused by Phomopsis vexans“. International Journal of Chemical Studies 8, Nr. 4 (01.07.2020): 2051–53. http://dx.doi.org/10.22271/chemi.2020.v8.i4v.9929.
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Úrbez-Torres, J. R., F. Peduto, R. J. Smith und W. D. Gubler. „Phomopsis Dieback: A Grapevine Trunk Disease Caused by Phomopsis viticola in California“. Plant Disease 97, Nr. 12 (Dezember 2013): 1571–79. http://dx.doi.org/10.1094/pdis-11-12-1072-re.
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Field surveys recently conducted in California and in other grape-growing regions in the United States showed Phomopsis viticola to be one of the most prevalent fungi isolated from grapevine perennial cankers in declining vines. The current study has not only confirmed the presence of P. viticola from grapevine cankers in California but also has for the first time revealed the occurrence of Diaporthe ambigua, D. eres, and D. neotheicola in symptomatic grapevine wood in California by means of morphological studies and multi-gene sequence analysis. Pathogenicity trials conducted on mature cordons of Vitis vinifera ‘Syrah’ and ‘Red Globe’, as well as on lignified Syrah dormant canes, showed P. viticola isolates from California to be capable of causing perennial cankers. Lengths of vascular discoloration caused by P. viticola were similar to those caused by Eutypa lata and several Botryosphaeriaceae spp., which are well-known grapevine trunk disease pathogens. Additionally, a lack of spring growth was commonly observed in dormant canes inoculated with P. viticola spore suspensions in two pathogenicity trials. As part of this study, V. vinifera ‘Cabernet Sauvignon’ and ‘Zinfandel’ wood was shown to be more susceptible to infection by P. viticola than ‘Barbera’, ‘Chardonnay’, ‘Merlot’, and ‘Thompson Seedless’ wood. After more than 40 years overlooking P. viticola as a grapevine wood pathogen, this study provides strong evidence of the role of P. viticola as a canker-causing organism, and suggests its addition to the fungi involved in the grapevine trunk disease complex. Results from this study suggest D. ambigua and D. neotheicola to be saprophytes or weak pathogens on grapevine wood.
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Bradley, C. A., G. L. Hartman, L. M. Wax und W. L. Pedersen. „Quality of Harvested Seed Associated with Soybean Cultivars and Herbicides Under Weed-Free Conditions“. Plant Disease 86, Nr. 9 (September 2002): 1036–42. http://dx.doi.org/10.1094/pdis.2002.86.9.1036.
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Different herbicides were applied to soybean plants in field plots planted to different soybean cultivars located at four locations in Illinois between 1997 and 2000. Treatments varied from hand weeded to preemergence herbicides to postemergence herbicides. Soybean seeds were harvested and evaluated for different seed quality parameters. The percentage of seeds infected with Phomopsis spp. ranged from 1 to 40%, and the percentage of seeds infected with Cercospora kikuchii was low, ranging from 0 to 4%. Herbicides had little or no effect on seed quality parameters such as percent germination and incidence of seed pathogens or on protein and oil concentrations. Soybean seed quality was affected by Phomopsis spp. in that there were significant (P ≤ 0.05) inverse correlations between Phomopsis spp. incidence and percentage seed germination. It appears that Phomopsis spp. may be a more prevalent seed pathogen than C. kikuchii for soybean fields in central to northern Illinois.
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Rehner, Stephen A., und Francis A. Uecker. „Nuclear ribosomal internal transcribed spacer phylogeny and host diversity in the coelomycete Phomopsis“. Canadian Journal of Botany 72, Nr. 11 (01.11.1994): 1666–74. http://dx.doi.org/10.1139/b94-204.
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Species concepts in Phomopsis are based primarily on host association because morphological and cultural characters are generally insufficient for species diagnosis. Increasingly, there are reports that some species of Phomopsis are not host restricted but are capable of infecting several or more taxonomically unrelated host genera. Phylogenetic analysis of nuclear ribosomal DNA internal transcribed spacer sequences (ITS1 and ITS2) for 43 North American and Caribbean strains of Phomopsis isolated from diverse plant hosts and geographic origins resolved three clades, provisionally termed groups A, B, and C. Group A consists of isolates from shrubs and trees originating primarily from eastern North America. Group B includes isolates from woody and herbaceous plants that originate from tropical to subtropical regions and produce paraphyses among their conidiogenous cells. Group C occurs primarily on herbaceous plant hosts, including agricultural field crops, and is widely distributed throughout temperate to subtropical North America. Isolates from Europe and Asia may be significantly different in ITS sequences compared with North American isolates. The diversity of host taxa associated with terminal clades in the ITS phylogeny suggests that either Phomopsis species infect more than one host or host switching occurs frequently during speciation. Key words: Ascomycotina, coelomycetes, Diaporthe, ITS, molecular phylogeny, Phomopsis.
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Battilani, P., A. Gualla, C. Dall'Asta, C. Pellacani, G. Galaverna, P. Giorni, A. Caglieri et al. „Phomopsins: an overview of phytopathological and chemical aspects, toxicity, analysis and occurrence“. World Mycotoxin Journal 4, Nr. 4 (01.01.2011): 345–59. http://dx.doi.org/10.3920/wmj2011.1302.
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Phomopsis leptostromiformis, and its teleomorph Diaporthe toxica, is a lupin pathogen that causes stem blight in young lupins and, as a saprophyte, has been detected on dead lupine material. Under favourable conditions, the fungus produces phomopsins (PHOs), a family of macrocyclic hexapeptide mycotoxins capable of binding tubulin through the tripeptide side chain. The toxic effects appear largely confined to the liver. In particular, the ingestion of PHO contaminated lupin stubble has been linked to lupinosis, a debilitating disease of sheep (the most sensitive animal) characterised by disorientation, blindness, lethargy, and eventually death. The chemical structures of PHO A, B and D have been identified. Analytical methods to determine PHOs are mainly enzyme-linked immunosorbent assays or chromatographic separations, in combination with ultraviolet and mass spectrometric detection. The data about the PHOs occurrence are limited to Australia, restricted to lupin seed. Only one survey has been carried out on lupin seeds and flours from the Swiss market. Not many strategies have been developed to limit lupin seed contamination. Efforts devoted to control lupinosis in Australia focused on the development of cultivars resistant to Phomopsis infection. There are few examples in literature of decontamination or detoxification of PHOs; moreover, they have been shown to be resistant to extensive processing, including cooking. Australia and New Zealand are the only countries that included PHOs in their mycotoxin regulations, with a limit of 5 µg/kg in lupin seeds and derived products. Phomopsins are poorly studied mycotoxins and risk assessment on PHOs has not been done at the European level. The collection of all available scientific data was requested by EFSA in a specific project and partners involved considered it of general interest preparing this review to highlight the limited available information, which indicate that the assessment of potential risk related to PHOs is currently not feasible.
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Anderson, T. R., R. I. Buzzell, B. R. Buttery und V. A. Dirks. „Incidence of pod and seed infection in two soybean lines differing in resistance to Phomopsis seed decay“. Canadian Journal of Plant Science 75, Nr. 2 (01.04.1995): 543–45. http://dx.doi.org/10.4141/cjps95-094.
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Two soybean (Glycine max) lines differing in resistance to Phomopsis seed decay were evaluated in field trials, over 3 yr, for time and incidence of pod and seed infection caused by Phomopsis longicolla, Diaporthe phaseolorum var. caulivora and D. p. var. sojae. Pod infection increased linearly with time but OX615 averaged 15% less than Coles at each sample date. Seed infection increased curvilinearly in conjunction with decreasing seed moisture with marked increases between the fifth and seventh weeks after flowering. At maturity, average seed infection was 69% in Coles and 28% in OX615. Key words:Glycine max, soybean, resistance to Phomopsis seed decay
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Filippi, Carla Valeria, Andres Corro Molas, Matias Dominguez, Denis Colombo, Nicolas Heinz, Carolina Troglia, Carla Maringolo et al. „Genome-Wide Association Studies in Sunflower: Towards Sclerotinia sclerotiorum and Diaporthe/Phomopsis Resistance Breeding“. Genes 13, Nr. 12 (14.12.2022): 2357. http://dx.doi.org/10.3390/genes13122357.
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Diseases caused by necrotrophic fungi, such as the cosmopolitan Sclerotinia sclerotiorum and the Diaporthe/Phomopsis complex, are among the most destructive diseases of sunflower worldwide. The lack of complete resistance combined with the inefficiency of chemical control makes assisted breeding the best strategy for disease control. In this work, we present an integrated genome-wide association (GWA) study investigating the response of a diverse panel of sunflower inbred lines to both pathogens. Phenotypic data for Sclerotinia head rot (SHR) consisted of five disease descriptors (disease incidence, DI; disease severity, DS; area under the disease progress curve for DI, AUDPCI, and DS, AUDPCS; and incubation period, IP). Two disease descriptors (DI and DS) were evaluated for two manifestations of Diaporthe/Phomopsis: Phomopsis stem canker (PSC) and Phomopsis head rot (PHR). In addition, a principal component (PC) analysis was used to derive transformed phenotypes as inputs to a univariate GWA (PC-GWA). Genotypic data comprised a panel of 4269 single nucleotide polymorphisms (SNP), generated via genotyping-by-sequencing. The GWA analysis revealed 24 unique marker–trait associations for SHR, 19 unique marker–trait associations for Diaporthe/Phomopsis diseases, and 7 markers associated with PC1 and PC2. No common markers were found for the response to the two pathogens. Nevertheless, epistatic interactions were identified between markers significantly associated with the response to S. sclerotiorum and Diaporthe/Phomopsis. This suggests that, while the main determinants of resistance may differ for the two pathogens, there could be an underlying common genetic basis. The exploration of regions physically close to the associated markers yielded 364 genes, of which 19 were predicted as putative disease resistance genes. This work presents the first simultaneous evaluation of two manifestations of Diaporthe/Phomopsis in sunflower, and undertakes a comprehensive GWA study by integrating PSC, PHR, and SHR data. The multiple regions identified, and their exploration to identify candidate genes, contribute not only to the understanding of the genetic basis of resistance, but also to the development of tools for assisted breeding.
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Rawnsley, B., T. J. Wicks, E. S. Scott und B. E. Stummer. „Diaporthe perjuncta Does Not Cause Phomopsis Cane and Leaf Spot Disease of Grapevine in Australia“. Plant Disease 88, Nr. 9 (September 2004): 1005–10. http://dx.doi.org/10.1094/pdis.2004.88.9.1005.
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In Australia, Diaporthe perjuncta (formerly known as Phomopsis taxon 1) and Phomopsis viticola (Phomopsis taxon 2) have been associated with Phomopsis cane and leaf spot of grapevine. Although P. viticola causes distinct leaf spots, as well as lesions on shoots and canes, the pathogenicity of D. perjuncta is relatively unknown. The pathogenicity of D. perjuncta and P. viticola was studied in relation to symptom expression and bud loss. Only P. viticola caused brown-black, longitudinal, necrotic lesions on stem tissue and leaf spots characteristic of the disease, whereas both D. perjuncta and P. viticola induced bleaching of dormant canes. Inoculation of dormant buds with D. perjuncta did not cause bud death. D. perjuncta and P. viticola were reisolated from inoculated tissue and into pure culture. D. perjuncta colonized the epidermis and cortex of the grapevine shoot but not the vascular tissue. D. perjuncta appears to be an endophyte, rather than a pathogen of grapevine.
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Chaukhe, AN, Dr MJ Patil, AG Tekale und VA Borude. „In-vitro efficacy of fungicides against Phomopsis vexans caused Phomopsis blight in Brinjal“. International Journal of Chemical Studies 8, Nr. 4 (01.07.2020): 2054–55. http://dx.doi.org/10.22271/chemi.2020.v8.i4v.9930.
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Hulke, Brent S., Samuel G. Markell, Nolan C. Kane und Febina M. Mathew. „Phomopsis stem canker of sunflower in North America: correlation with climate and solutions through breeding and management“. OCL 26 (2019): 13. http://dx.doi.org/10.1051/ocl/2019011.
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Climate change is occurring in the central US and is interacting with agroecological factors to increase biotic stress in sunflower. Certain species of Diaporthe cause Phomopsis stem canker in sunflower and other dicotyledonous weeds and crops. The increase in precipitation already observed in the states of North Dakota, South Dakota, and Minnesota have increased the chances of outbreaks of necrotrophic pathogens, like Diaporthe. We discuss how climate trends, combined with technological, management, and economic interactions, are correlated with increasing incidence of Phomopsis stem canker in these and adjacent areas in North America. Further, we discuss management options and the role of improved sunflower genetics in reducing Phomopsis stem canker outbreak risk.
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Cowling, WA, JG Allen und PM Wood. „Resistance to Phomopsis stem blight reduces the lupinosis toxicity of narrow-leafed lupin stems“. Australian Journal of Experimental Agriculture 28, Nr. 2 (1988): 195. http://dx.doi.org/10.1071/ea9880195.
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To determine if resistance to Phomopsis stem blight reduced the lupinosis toxicity of stems in sheep, we tested mature, dry stems of several selected lines of Lupinus angustifolius L. (narrow-leafed lupin). Resistance was defined as a significant reduction in Phomopsis stem blight symptoms on mature, dry stems compared with susceptible cultivars. Six experiments were conducted at 4 sites in Western Australia in 1983 and 1984. Mature, dry stems were collected from field plots of resistant and susceptible lines for assessment of the frequency of isolation of Phomopsis leptostromiformis (Knhn) Bubak from stem tissue and toxicity to sheep 0 and 14 weeks after the normal time for seed harvest. In both years, P. lepto-stromiformis was isolated with high frequency from susceptible cultivars but with reduced frequency from only some resistant lines. Similarly, toxicity was significantly reduced in some but not all resistant lines. The variation in toxicity among lines could not be fully explained by their relative resistance or frequency of isolation of P. leptostromiformis. Symptoms of Phomopsis stem blight, frequencies of isolation of P. leptostromiformis, and toxicity increased from 0 to 14 weeks after normal harvest time. New lupin lines resistant to Phomopsis stem blight will require testing in field grazing experiments at several sites and for many seasons to confirm their potential for reducing the occurrence of lupinosis.
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Arestova, N. O., und I. O. Ryabchun. „HARMFULNESS OF THE FUNGAL DISEASE PHOMOPSIS IN THE VINE-YARDS OF THE ROSTOV REGION“. Russian Vine 19 (2022): 3–9. http://dx.doi.org/10.32904/2712-8245-2022-19-3-9.
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The results of studies of the influence of me-teorological conditions on the intensity of the development of Phomopsis (Phomopsis viti-cola) on plants of different grapevine varie-ties during 2019‒2021 are presented. It was established that the absence of extreme sub-zero temperatures during dormant period con-tributed to the preservation of the infectious onset of the disease. In most phases of the growing season 2019‒2021 unfavorable me-teorological conditions for the development of pycnidia and sporulation of the fungus Phomopsis viticola were observed ‒ high temperature and low air humidity. Despite this, the activity of the pathogen increased during the vegetation season and reached its maximum values in the phase of technical ma-turity of berries. Amoung the studied varie-ties, the most susceptible to Phomopsis were: Tsvetochny, Cabernet Sauvignon, Vostorg, Baklanovsky with a lesion intensity of more than 2 points. The most resistant varieties, with the intensity of damage up to 1 point and without signs of damage, were the fol-lowing varieties: Denisovsky, Pervenets Magarach, Krasnostop Zolotovsky, Sibirkovy.
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Monteiro, Sara, Mahmoud Barakat, Maria A. Piçarra-Pereira, Artur R. Teixeira und Ricardo B. Ferreira. „Osmotin and Thaumatin from Grape: A Putative General Defense Mechanism Against Pathogenic Fungi“. Phytopathology® 93, Nr. 12 (Dezember 2003): 1505–12. http://dx.doi.org/10.1094/phyto.2003.93.12.1505.
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Little information is available concerning the expression of pathogenesis-related (PR) proteins in grapevine (Vitis vinifera) and their effect properties on the major fungal pathogens of grape. A systematic study was performed on the effect of total or individual grape proteins on mycelial growth, spore germination, and germ tube growth of Uncinula necator, Phomopsis viticola, and Botrytis cinerea. Two proteins, identified as PR proteins by immunological methods and by N-terminal sequencing as osmotin and thaumatin-like protein, exhibited strong antifungal activities in vitro, blocking the growth of Phomopsis viticola and Botrytis cinerea mycelia. In addition, they inhibited spore germination and germ tube growth of U. necator, Phomopsis viticola, and Botrytis cinerea. The presence of both proteins displayed a synergistic effect. The expression of osmotin and thaumatin-like protein was induced in grapevine leaves and berries infected with U. necator and Phomopsis viticola. Thaumatin previously was thought to occur exclusively in berries. Immunoblot analyses revealed the accumulation of the two PR proteins in infected leaves and berries, supporting a role in vivo in increasing the resistance of grapevine to fungal attack.
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Ghissi, Valéria Cecília, Erlei Melo Reis und Carolina Cardoso Deuner. „Etiology of phomopsis root rot in soybean“. Summa Phytopathologica 40, Nr. 3 (September 2014): 270–72. http://dx.doi.org/10.1590/0100-5405/1966.
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In a survey of damages caused by soybean root rot to crops in the south of Brazil for several years, a root rot caused by Phomopsis sp has been found with increasing frequency. The primary symptoms are seen when the main root is cut longitudinally, including the death of the wood which shows white coloration and well-defined black lines that do not have a defined format. Thus, based on similarity, it has been called geographic root rot due to its aspect resembling irregular lines that separate regions on a map. In isolations, colonies and alpha spores of Phomopsis have prevailed. Pathogenicity test was done by means of inoculation in the crown of plants cultivated in a growth chamber. The geographic symptoms were reproduced in plants and the fungus Phomopsis sp. was reisolated. In soybean stems naturally infected with pod and stem blight, geographic symptoms caused by Phomopsis phaseoli are found. To the known symptoms on stems, pods and grains, that of root rot caused by P. phaseoli is now added.
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Borovskaya, I., und V. Petrenkova. „Zonal pathogen complex of sunflower in the left bank Forest-Steppe of Ukraine“. Agricultural Science and Practice 5, Nr. 1 (15.04.2018): 67–72. http://dx.doi.org/10.15407/agrisp5.01.067.
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Aim. To determine a set of sunfl ower pathogens and their variability infl uenced by hydrothermal conditions of the crop growing season. Methods. Over the period of 2007–2016, due to phytosanitary monitoring of breeding crops of the scientifi c crop rotation of the Plant Production Institute named after V.Ya. Yuriev of NAAS, the prevalence degree, development intensity and variability of sunfl ower diseases in the Eastern Forest-Steppe of Ukraine were estimated. The hydrothermal coeffi cient (HTC) is presented for the sunfl ower growing season and by developmental phases of the crop. Results. Phomopsis blight (Phomopsis/Diaporthe helianthi Munt.- Cvet. et al.), gray mold (Botrytis cinerea Pers.), dry rot (Rhizopus sp.), charcoal rot (Sclerotium bataticolaTaub), and downy mildew (Plasmopara helianthi Novot. f. helianthi) were the most common diseases on sunfl ower in the Eastern Forest-Steppe of Ukraine in 2007–2016. The weather conditions of 2007–2016 considerably varied and were characterized by fl uctuations in the hydrothermal coeffi cient (HTC) from 0.57 in 2009 to 1.1 in 2014. Assessing the incidence of the fi ve most common and harmful sunfl ower diseases (dry rot, charcoal rot, gray mold, Phomopsis blight, downy mildew) by cluster analysis for the ten-year study period in relation to the weather conditions of a year, we found that both dry and charcoal rots were co-associated with aridity, while downy mildew and gray mold were frequently promoted by waterlogging during a certain period of sunfl ower development. Unlike the other diseases, Phomopsis blight, being an annual disease, appears to have no clear dependence on any specifi c conditions. Conclusions. Based on the phytosanitary monitoring results of crops in the Eastern Forest-Steppe of Ukraine, the sunfl ower phytopathogen complex composition was determined. The prevalence degrees for Phomopsis blight, gray mold, dry rot, charcoal rot, and downy mildew as well as the development intensities of Phomopsis and gray mold were established. The co-incidence of the fi ve most harmful sunfl ower diseases in the Eastern Forest-Steppe of Ukraine (dry rot, charcoal rot, gray mold, Phomopsis blight, downy mildew) was evaluated during the ten-year study period, depending on the weather conditions of a year.
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Ormeno-Nunez, J., R. D. Reeleder und A. K. Watson. „A new species of Phomopsis recovered from field bindweed (Convolvulus arvensis)“. Canadian Journal of Botany 66, Nr. 11 (01.11.1988): 2228–33. http://dx.doi.org/10.1139/b88-305.
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Isolates of a Phomopsis recovered from diseased foliage of Convolvulus arvensis L. were morphologically distinct from other species of Phomopsis. Alpha-conidia were oblong to fusiform-ellipsoid, usually blunt at both ends with two guttules, and were distinctly larger than alpha-conidia of previously reported species. Beta-conidia were found only in culture. Stromata developed as small, superficial masses of aggregated mycelium, later becoming pulvinate, and were dark brown to black. Stromata were scattered throughout the colony, rarely aggregated. Pycnidia were uniostiolate or multiostiolate, usually arising from the stromata bodies, and pycnidial beaks were prominent. Leaf spot and anthracnose symptoms were reproduced on inoculated bindweed plants. The binomial Phomopsis convolvulus is proposed for this taxon.
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ANJOS, JOSÉ R. N., MARIA J. A. CHARCHAR und DANIEL P. GUIMARÃES. „Ocorrência de queima das folhas causada por Phomopsis sp. em Aroeira no Distrito Federal“. Fitopatologia Brasileira 26, Nr. 3 (September 2001): 549–650. http://dx.doi.org/10.1590/s0100-41582001000300012.
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O fungo Phomopsis sp. foi consistentemente isolado de plantas de aroeira (Myracrodruon urundeuva.) com sintomas de queima nas folhas, no Distrito Federal, em 1999. Testes de patogenicidade em casa de vegetação confirmaram Phomopsis sp. como o agente etiológico da doença. Dezesseis, de 20 outras espécies vegetais inoculadas em condições similares, também foram suscetíveis ao fungo.
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Børja, Isabella, Halvor Solheim, Ari M. Hietala und Carl Gunnar Fossdal. „Etiology and Real-Time Polymerase Chain Reaction-Based Detection of Gremmeniella- and Phomopsis-Associated Disease in Norway Spruce Seedlings“. Phytopathology® 96, Nr. 12 (Dezember 2006): 1305–14. http://dx.doi.org/10.1094/phyto-96-1305.
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In spring 2002, an unusual disease outburst was recorded on Norway spruce seedlings in southeast Norway. Extensive damage was recorded on 1- and 2-year-old Norway spruce seedlings that either had wintered in nursery cold storage or had been planted out in autumn 2001. The damage was characterized by leader shoot dieback and stem necroses on the upper or lower part of the shoot from 2001. Gremmeniella abietina and a Phomopsis sp. frequently were isolated from the diseased seedlings. Internal transcribed spacer (ITS) ribosomal (r)DNA sequence analysis and random amplified microsatellites profiling indicated that the G. abietina strains associated with diseased nursery seedlings belonged to the large-tree type (LTT) ecotype of the European race of G. abietina var. abietina, and inoculation tests confirmed their pathogenicity on Norway spruce. Based on ITS rDNA sequence analysis, the Phomopsis strains associated with diseased seedlings did not represent any characterized Phomopsis spp. associated with conifers. The Phomopsis sp. was not pathogenic in inoculation tests, indicating that it may be a secondary colonizer. ITS-based real-time polymerase chain reaction assays were developed in order to detect and quantify G. abietina and Phomopsis in the nursery stock. We describe here the G. abietina-associated shoot dieback symptoms on Norway spruce seedlings and conclude that the unusual disease outburst likely was related to the G. abietina var. abietina epidemic caused by the LTT on large Scots pines in 2001.
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Li, Shuxian, und Youjin Deng. „Mitochondrial Genome Resource of Phomopsis longicolla, a Fungus Causing Phomopsis Seed Decay in Soybean“. PhytoFrontiers™ 1, Nr. 2 (April 2021): 120–22. http://dx.doi.org/10.1094/phytofr-10-20-0027-a.
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Phomopsis seed decay is one of the most devastating seed diseases reducing soybean seed quality worldwide. This disease is caused primarily by a seed-borne fungus, Phomopsis longicolla (syn. Diaporthe longicolla). As part of a genome sequencing project for P. longicolla, we present the mitochondrial genome resource of the isolate MSPL 10-6, one of the most aggressive field isolates. The circular mitochondrial genome is 53,646 bp long with GC content of 34.27%, and it encodes 14 common protein genes, 23 tRNA and two rRNA genes, and 10 introns. Forty-five SNPs and InDels also were identified during comparative analyses with another isolate. The mitochondrial genome sequence provides a useful resource for developing molecular markers for pathogen detection and for improvement of control strategies for the disease. [Formula: see text] Copyright © 2021 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license .
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Karaoglanidis, G. S., und G. Bardas. „First Report of Phomopsis Fruit Decay on Apple Caused by Phomopsis mali in Greece“. Plant Disease 90, Nr. 3 (März 2006): 375. http://dx.doi.org/10.1094/pd-90-0375c.
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From 2002 to 2005, a previously unreported disease causing significant yield losses was observed on apple fruits (cv. Red Chief) in the region of Imathia in northern Greece. Almost all apple orchards in that area, cultivated with Red Chief, showed disease symptoms on 3 to 10% of the fruits. Diseased fruits showed irregularly shaped, water-soaked areas on the skin and extensive decay internally. In most of the fruits, decay appeared to initiate internally from the calyx tube. Infected fruits remained firm during the early stages of decay. Fungal isolates obtained from small pieces of decayed tissue on potato dextrose agar (PDA) medium were identified as Phomopsis mali Roberts on the basis of morphological characteristics (2). Cultures grew rapidly on PDA at 22°C in the dark. They were initially white, but approximately 30 days after inoculation they turned gray because of the formation of pycnidia that contained α- and β-spores. α -Spores were short and elliptical in shape (8 to 10 × 2 to 3 μm) while β-spores were long (22 to 25 × 1 to 2 μm). Pathogenicity of the isolated cultures was tested by wound inoculating five mature apple fruits (cv. Red Chief) after surface sterilization with 0.5% NaOCl. PDA plugs, 5 mm in diameter with actively growing mycelium, were transferred into the flesh of the fruits. Sterile PDA plugs were used to inoculate five control apple fruits. Inoculated fruits were kept at 23°C for 10 days in the growth chamber. Extensive decay, similar to that observed on diseased fruits in the field, was observed on the inoculated fruits, whereas control fruits showed no decay. P. mali was reisolated from the decayed tissues. Commercial losses due to fruit decay caused by the pathogen have previously been reported in the United States and Northern Ireland (1). To our knowledge, this is the first report of Phomopsis fruit decay on apples in Greece. References: (1) A. C. Jones and H. S. Aldwinckle eds. Compendium of Apple and Pear Diseases. The American Phytopathological Society. St. Paul, MN, 1990. (2) D. A. Rosenberger and T. J. Burr.
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Meyer, M. D., G. R. Zhang, D. K. Pedersen und C. A. Bradley. „First Report of Phomopsis Stem Canker of Sunflower in Illinois Caused by Phomopsis helianthi“. Plant Disease 93, Nr. 7 (Juli 2009): 760. http://dx.doi.org/10.1094/pdis-93-7-0760a.
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Stem cankers were observed on confection sunflower (Helianthus annuus) plants growing in a field in Champaign County, Illinois in August 2008. Lesions were brown to reddish brown, elongated (approximately 10 to 15 cm long), and centered over the area where leaf petioles connected to the stems. Stem tissues underneath the lesions were degraded. Lesions from diseased stems were cut into 5- to 7-mm pieces and immersed in a 0.5% NaOCl solution for 1 min, rinsed with sterilized distilled water, and placed into petri dishes containing acidified potato dextrose agar (APDA; 4 ml of 25% lactic acid per liter). Fungal colonies that grew from the stem lesion pieces on APDA were white, floccose, and dense with dark colored substrate mycelia. On the basis of the symptoms on sunflower plants and the growth characteristics on APDA, the fungus was tentatively identified as Phomopsis helianthi (1). To confirm the identity of the fungus, PCR amplification of the small subunit rDNA and internal transcribed spacer (ITS) region with primers EF3RCNL and ITS4 was done (2). The PCR product was sequenced with these primers at the Keck Biotechnology Center at the University of Illinois, Urbana. The resulting nucleotide sequence was compared with small subunit rDNA and ITS sequences deposited in the nucleotide database ( http://www.ncbi.nlm.nih.gov ) and showed highest homology to sequences of Diaporthe helianthi, teleomorph of P. helianthi. To confirm pathogenicity of the fungus, sunflower plants (cv. Cargill 270) were grown in the greenhouse and inoculated with the isolated fungus. The stems of sunflower plants between the V2 and V4 growth stages (3) were excised just below the uppermost node. Mycelia plugs of the fungus were placed into the large end of disposable micropipette tips (200 μl). The micropipette tip containing the fungus was subsequently placed over a cut sunflower stem. The fungal isolate was used to inoculate five stems. To serve as controls, five cut sunflower stems were inoculated with micropipette tips containing plugs of noninfested PDA and five cut stems were not inoculated. Mean lesion length on the stem was measured from the inoculated tip toward the soil line 7 days after inoculation. The experiment was replicated over time. Mean lesion length over both replications averaged 24 mm on the fungus-inoculated plants, 2 mm on the noninfested PDA-inoculated control plants, and no lesions were present on the noninoculated control plants. The fungus was reisolated on PDA from the inoculated plants in the greenhouse. To our knowledge, this is the first report of P. helianthi causing a stem canker of sunflower in Illinois. Although commercial sunflower production in Illinois is currently limited, it is being evaluated as a potential crop to follow winter wheat in portions of the state. If sunflower production were to increase in the state, growers may have to monitor for and manage Phomopsis stem canker. References: (1) T. Gulya et al. Sunflower diseases. Page 263 in: Sunflower Technology and Production. American Society of Agronomy, Madison, WI, 1997. (2) N. S. Lord et al. FEMS Microbiol. Ecol. 42:327, 2002. (3) A. A. Schneiter and J. F. Miller, Crop Sci. 21:901, 1981.
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Meng, Fan-Bing, Zhen-Zhen Gou, Yun-Cheng Li, Long-Hua Zou, Wei-Jun Chen und Da-Yu Liu. „The Efficiency of Lemon Essential Oil-Based Nanoemulsions on the Inhibition of Phomopsis sp. and Reduction of Postharvest Decay of Kiwifruit“. Foods 11, Nr. 10 (22.05.2022): 1510. http://dx.doi.org/10.3390/foods11101510.
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Essential oils (EOs) have excellent antibacterial activity and are generally recognized as safe (GRAS) for use in food preservatives. However, the application of EOs is limited because of their strong volatility and easily oxidized. Encapsulation of EOs into nanoemulsions could effectively prevent oxidative deterioration. In this study, lemon essential oil-based nanoemulsion (LEO/NE) was prepared by high-pressure homogenization. FT-IR and encapsulation efficiency analysis indicated that LEO was effectively encapsulated in the nanoemulsion. The results of zeta potential changes after 35 d storage indicated that LEO/NE exhibits good stability at room temperature. The effect of LEO/NE on the main soft rot pathogens of kiwifruit Phomopsis sp. was investigated, and the results showed that LEO/NE significantly inhibited spore germination and mycelia growth of Phomopsis sp. by promoting ROS accumulation, intracellular antioxidant enzyme activities, and cell apoptosis. The preservation experiment was carried out by inoculating Phomopsis sp. spores into fresh kiwifruit, and the LEO/NE effectively inhibited soft rot development in kiwifruit in a LEO dose dependent manner. LEO/NE with 1% LEO loading amount has a good effect on preventing postharvest decay of kiwifruit caused by Phomopsis sp.
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Cheah, L.-H., C. M. Horlock und R. D. Davis. „Field survey to assess spread of new asparagus diseases in Queensland“. New Zealand Plant Protection 56 (01.08.2003): 106–8. http://dx.doi.org/10.30843/nzpp.2003.56.6047.
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Asparagus (Asparagus officinalis) crops on eight Queensland properties were surveyed for the presence of asparagus rust (caused by Puccinia asparagi) phomopsis stem blight (caused by Phomopsis asparagi) and asparagus anthracnose (caused by Colletotrichum gloeosporioides) in November 2002 All properties surveyed had a low incidence of rust disease Most rust developed on plants two weeks after spear emergence No symptoms of phomopsis stem blight or anthracnose were found in the Mundubbera and Beerburrum regions Anthracnose was found only in Mareeba (northern Queensland) The incidence of phomopsis stem blight was found to be high on one property in the Warwick region Examination of diseased plants showed that the respective pathogens were associated with the symptoms Drought was a major problem for growers and we observed that crops with an appropriate fertiliser and irrigation regime showed increased plant growth and less disease Crops with irrigation alone also showed better growth and less disease than those without irrigation Our observations suggest that an appropriate irrigation and fertiliser regime that promotes plant growth and health will lessen the likelihood of infection by these diseases However more research is required to confirm this
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Cross, Cory, Allen Wrather, Kent Fothergill, Grover Shannon, Shuxian Li, Calvin Shumway und John Rupe. „Effect of Lactofen, Azoxystrobin, and Genotypes on Charcoal Rot, Phomopsis Seed Decay, and Pod and Stem Blight in Soybean“. Plant Disease 96, Nr. 8 (August 2012): 1154–58. http://dx.doi.org/10.1094/pdis-09-11-0810-re.
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Yield-limiting diseases such as charcoal rot and Phomopsis seed decay have a significant impact on the economic potential for soybean because there are few methods for management of these diseases. The objectives of this study were to determine the development of charcoal rot, infection of seed by Phomopsis spp., and severity of pod and stem blight on Asgrow 4403, Delta Pine 5806, United States Department of Agriculture–introduced DT 97-4290 and plant introduction (PI) number PI 567562A, and Asgrow 4403 treated and not treated with lactofen or azoxystrobin. This is the first report of high levels of resistance in PI 567562A to charcoal rot, and resistance in this PI was greater than for DT 97-4290. Application of lactofen at growth stage R1 and azoxystrobin at either planting, R3, or R6 had no significant impact on severity of charcoal rot, percentage of harvested seed infected by Phomopsis spp., or severity of pod and stem blight on genotype Asgrow 4403. Of four genotypes evaluated, none were resistant to infection by Phomopsis spp. The genotypes Asgrow 4403, DP 5806, and DT 97-4290 were susceptible to pod and stem blight and PI 567562A was resistant.
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OPREA, Daniela, Maria JOITA-PACUREANU, Florin Gabriel ANTON und Luxita RISNOVEANU. „The Resistance of Sunflower to the Attack of Some Pathogenic Agents in the Climate Conditions of the Northeast Baragan“. Bulletin of University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca. Agriculture 79, Nr. 2 (20.11.2022): 54–58. http://dx.doi.org/10.15835/buasvmcn-agr:2022.0034.
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Due to its national economic importance, the sunflower crop has established itself as the main oleaginous crop cultivated in Romania. It faces several diseases that are difficult to fight chemically. The creation of hybrids resistant to the attack of pathogens has proven to be an effective, safe, and environmentally friendly solution. This paper aims to examine the resistance of some biological sunflower creations created in Romania, to the attack of Phomopsis helianthi and Phoma macdonaldi fungi, in 2021. The experiment was placed in field conditions with a natural infestation, at A.R.D.S. Braila. The used biological material was represented by nine new sunflower hybrids. Two problem pathogens were studied: Phomopsis helianthi (perfect stage Diaporthe helianthi) and Phoma macdonaldi (perfect stage Leptosphaeria lindquistii). The climatic conditions of 2021 were favorable for the growth of the pathogens. Phoma macdonaldi had an average attack frequency of 38.8% and an average attack intensity of 1.71%, while Phomopsis helianthi recorded average values of 67.8% and 3.08%, respectively. The lowest attack degree of the Phoma macdonaldi pathogen was found in H3 (0.35%). Regarding the pathogen Phomopsis helianthi, the hybrid H3 showed good resistance, with an attack degree of 1.64%.
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Culvenor, Claude C. J., John A. Edgar, Maureen F. Mackay, Charles P. Gorst-Allman, Walter F.O. Marasas, Pieter S. Steyn, Robert Vleggaar und Philippus L. Wessels. „Structure elucidation and absolute configuration of phomopsin a, a hexapeptide mycotoxin produced by phomopsis leptostromiformis“. Tetrahedron 45, Nr. 8 (Januar 1989): 2351–72. http://dx.doi.org/10.1016/s0040-4020(01)83436-0.
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Ondřej, M., L. Odstrčilová und R. Dostálová. „Phomopsis pisi – a new species causing pea stem canker“. Plant Protection Science 42, No. 3 (10.02.2010): 95–98. http://dx.doi.org/10.17221/2756-pps.
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The new species <i>Phomopsis pisi</i> Ondřej sp. n. (Anamorphic Fungi – Coelomycetes) occurred on stems of pea (<i>Pisum sativum</i> L.) cv. Adept at Šumperk-Temenice (Czech Republic). The fungus caused plants to die at the green maturity stage. The new species differs from Phomopsis pisicola. It differs in the length and width of conidiophores and conidia.
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Charchar, Maria José d' A., José R. N. Anjos und José T. Melo. „Infecção natural de jatobá por Phomopsis sp. no Distrito Federal“. Fitopatologia Brasileira 28, Nr. 3 (Juni 2003): 316–18. http://dx.doi.org/10.1590/s0100-41582003000300016.
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No ano de 1999, no Distrito Federal, em plantas de jatobá (Hymenaea stigonocarpa) foram observados sintomas de lesões foliares de onde foi isolado o fungo Phomopsis sp. Em condições de casa de vegetação, foram inoculadas folhas com o fungo em dez plantas de jatobá e dez foram mantidas como controle. Os sintomas desenvolvidos nas plantas inoculadas com ferimento foram observados no sétimo dia após inoculação, de onde o fungo Phomopsis sp. foi reisolado. Nas plantas controle não foram observados sintomas. Este é o primeiro relato de Phomopsis sp. em folhas de jatobá, no Brasil, em condições naturais. De 13 espécies vegetais testadas para patogenicidade com este isolado, seguindo-se a mesma metodologia de inoculação 12 foram suscetíveis e apenas o maracujá-azedo (Passiflora edulis f. flavicarpa) não apresentou sintomas.
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Cheah, L.-H., und C. M. Horlock. „Fieldapplied fungicides and postharvest treatments to control asparagus diseases posing biosecurity threats to New Zealand“. New Zealand Plant Protection 60 (01.08.2007): 94–98. http://dx.doi.org/10.30843/nzpp.2007.60.4631.
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Collaborative research between New Zealand and Australia has investigated fieldapplied fungicides and postharvest treatments for control of asparagus rust (caused by Puccinia asparagi) and phomopsis stem blight of asparagus (caused by Phomopsis asparagi) in Queensland In a 2004 field trial the fungicides difenoconazole and propiconazole reduced the incidence of asparagus rust In a 2005 field trial four fungicides (carbendazim chlorothalonil iprodione and propiconazole) reduced the severity of phomopsis stem blight Postharvest disinfection with sodium hypochlorite or with calcium hypochlorite at 150 ppm was highly effective at reducing Pu asparagi and Ph asparagi spore germination on water agar Integrated disease management based on field and postharvest methods are suggested to reduce the risk of importation of the diseases to New Zealand Similar methods could be used for controlling these diseases if they establish
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Baird, R. E., T. S. Abney und B. G. Mullinix. „Fungi associated with pods and seeds during the R6 and R8 stages of four soybean cultivars in southwestern Indiana“. Phytoprotection 82, Nr. 1 (12.04.2005): 1–11. http://dx.doi.org/10.7202/706210ar.
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A total of 6,403 isolates of fungi were identified from soybean pods and seeds collected late in the 1992 and 1993 growing season (R6 and R8 soybean growth stages). The majority of fungi consisted of Deuteromycetes (95.5%) followed by Ascomycetes (0.9%). Common fungal genera isolated during the study included Phomopsis, Alternaria, Cercospora, and Colletotrichum (= Glomerella) . Cercospora and Phomopsis were identified more commonly from pods and seeds at harvest maturity (R8) than at the greenbean stage of development (R6). However, isolation frequencies of Colletotrichum were greater from tissues collected at R6 than at R8. Isolation frequencies compared between pod and seed tissue were similar for almost all the fungi except Alternaria, Phoma, and Nigrospora. The primary pathogenic species identified from the Diaporthe/Phomopsis complex were D. phaseolorum var. caulivora and D. phaseolorum var. sojae at 28.2% of the total isolation frequencies compared to D. phaseolorum var. meridionalis and Phomopsis longicolla that were identified from 1% of the total samples. The pod tissue harbored greater numbers of fungi than seeds during this study. In statistical comparisons of the peduncle, middle, and stylar regions from pods, no differences in isolation frequencies were found for the cultivars tested regardless if pod tissues or seeds were compared. In summary, the percent isolation frequency of pathogenic fungi from pod and seed at R6 was an effective indicator of the potential for increased disease severity. Furthermore, the significantly greater occurrence of D. phaseolorum var. caulivora and D. phaseolorum var. sojae compared to the other Phomopsis/Diaporthe spp. (e.g. D. phaseolorum var. meridionalis) in southern Indiana will enable scientists to continue to concentrate their breeding efforts for resistance to control these two major pathogens.
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Xu, Tang-Chang, Yi-Han Lu, Jun-Fei Wang, Zhi-Qiang Song, Ya-Ge Hou, Si-Si Liu, Chuan-Sheng Liu und Shao-Hua Wu. „Bioactive Secondary Metabolites of the Genus Diaporthe and Anamorph Phomopsis from Terrestrial and Marine Habitats and Endophytes: 2010–2019“. Microorganisms 9, Nr. 2 (21.01.2021): 217. http://dx.doi.org/10.3390/microorganisms9020217.
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The genus Diaporthe and its anamorph Phomopsis are distributed worldwide in many ecosystems. They are regarded as potential sources for producing diverse bioactive metabolites. Most species are attributed to plant pathogens, non-pathogenic endophytes, or saprobes in terrestrial host plants. They colonize in the early parasitic tissue of plants, provide a variety of nutrients in the cycle of parasitism and saprophytism, and participate in the basic metabolic process of plants. In the past ten years, many studies have been focused on the discovery of new species and biological secondary metabolites from this genus. In this review, we summarize a total of 335 bioactive secondary metabolites isolated from 26 known species and various unidentified species of Diaporthe and Phomopsis during 2010–2019. Overall, there are 106 bioactive compounds derived from Diaporthe and 246 from Phomopsis, while 17 compounds are found in both of them. They are classified into polyketides, terpenoids, steroids, macrolides, ten-membered lactones, alkaloids, flavonoids, and fatty acids. Polyketides constitute the main chemical population, accounting for 64%. Meanwhile, their bioactivities mainly involve cytotoxic, antifungal, antibacterial, antiviral, antioxidant, anti-inflammatory, anti-algae, phytotoxic, and enzyme inhibitory activities. Diaporthe and Phomopsis exhibit their potent talents in the discovery of small molecules for drug candidates.
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SAVU, Sergiu, Liliana Lucia TOMOIAGA und Veronica Sanda CHEDEA. „Ecological Microclimate Influence on Grapevine Phomopsis viticola Attack Frequency in Aiud-Ciumbrud Vineyards“. Bulletin of University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca. Horticulture 77, Nr. 2 (18.11.2020): 64. http://dx.doi.org/10.15835/buasvmcn-hort:2020.0026.
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Phomopsis viticola (Sacc.) Sacc. (syn. Cryptosporella viticola Shear, Diaporthe viticola Nitschke, Diplodia viticola Desm, Fusicoccum viticolum Reddick, Phoma flaccida Viala & Ravaz, Phoma viticola Sacc.), is the causal agent of the grapevine disease named ‘Phomopsis cane’ and ‘Leaf spot’ in the U.S.A. or ‘Excoriose’ in Europe. This study aims to evaluate the influence of the microclimate on Phomopsis viticola attack in Aiud-Ciumbrud vineyards. The observations were done on four plots in Aiud-Ciumbrud vineyards in the period March-August 2020. Up to the end of August 2020, ten treatments with contact and systemic products based on metiram and sulphour were done together with the other standard agro-technological operations. In the ecological conditions of spring-summer 2020, with higher temperature than the average in January, February, March and June, more rain than the average in February, March and June and less rain in January, April and May, we found frequency of the excoriosis in the range of 4%-12% at the beginning of the season. After the fungicide treatments, the attack frequency decreased up to 0%-7%. In the present research work, we show that in Aiud-Ciumbrud vineyards Phomopsis viticola attack was present and influenced by the microclimate conditions and also it was reduced by the fungicide treatments.
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Tongsri, Veeranee, Pattavipha Songkumarn und Somsiri Sangchote. „Leaf Spot Characteristics of Phomopsis Durionis on Durian (Durio Zibethinus Murray) and Latent Infection of the Pathogen“. Acta Universitatis Agriculturae et Silviculturae Mendelianae Brunensis 64, Nr. 1 (2016): 185–93. http://dx.doi.org/10.11118/actaun201664010185.
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A survey of leaf spot disease on durian caused by Phomopsis durionis was conducted in durian growing areas in eastern Thailand, Chanthaburi and Trat provinces. It was found that lesions with yellow halos on both mature and young leaves are variable in sizes (1–10 mm in diameter). In this study, nine morphologically distinct isolates of Phomopsis were obtained from durian leaf spots. Some of them produced small number of pycnidia on potato dextrose agar after incubation for 30 days. Artificial inoculation on wounded leaves of durian seedlings, resulted in the production of browning areas with yellow halos and pycnidium formation at 13 days and 20 days after inoculation, respectively. Furthermore, red-brown spots with yellow halos on leaf tissues were observed at 32 days after inoculation. High density of Phomopsis was observed in durian symptomless leaves and flowers indicated the latent infection of the pathogen in the fields. Interestingly, crude extract of durian leaf with preformed substances demonstrated inhibition of spore germination and germ tube growth of the pathogen, Phomopsis sp., on water agar. In addition, bioassay on TLC plate displayed inhibition zone of growth of the fungus, Cladosporium oxysporum at retention factor (Rf) of 0.29–0.88. This indicates that preformed substances in leaf tissues might act as compounds affecting latent period of pathogen.
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Koning, G., D. M. TeKrony und S. A. Ghabrial. „Soybean Seedcoat Mottling: Association with Soybean mosaic virus and Phomopsis spp. Seed Infection“. Plant Disease 87, Nr. 4 (April 2003): 413–17. http://dx.doi.org/10.1094/pdis.2003.87.4.413.
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Soybean mosaic virus (SMV) infection predisposes soybean (Glycine max) seed to Phomopsis spp. seed infection and may induce seedcoat mottling. The extent of seedcoat mottling associated with the accumulation of SMV or Phomopsis spp. infection of the seedcoat was investigated in 1996 and 1997. Plants of two SMV-susceptible cultivars, ‘Clark’ and ‘Williams’, were sap inoculated with the G2 strain of SMV at growth stage R2. Control plants (SMV-resistant isolines L78-434 and L78-379, respectively) were not inoculated. Harvested seed were evaluated visually for seedcoat mottling and sorted into four categories (severe, banded, blemish, and none) according to the degree of seedcoat pigmentation. Seed infection with Phomopsis spp. was determined and SMV accumulation was assessed by enzyme-linked immunosorbent assay and nucleic acid hybridization analysis. Phomopsis spp. were isolated from seed of all mottling categories, with the incidence of infection increasing as the degree of seedcoat mottling increased. SMV was detected in both mottled and nonmottled seedcoats, with generally higher levels of SMV in mottled seedcoats. However, the relationship of SMV titer to seedcoat mottling was inconsistent across cultivars and years. Thus, the extent of seedcoat mottling was not directly related to the accumulation of SMV in the seedcoat.
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Mathew, Febina M., Kholoud M. Alananbeh, James G. Jordahl, Scott M. Meyer, Lisa A. Castlebury, Thomas J. Gulya und Samuel G. Markell. „Phomopsis Stem Canker: A Reemerging Threat to Sunflower (Helianthus annuus) in the United States“. Phytopathology® 105, Nr. 7 (Juli 2015): 990–97. http://dx.doi.org/10.1094/phyto-11-14-0336-fi.
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Phomopsis stem canker causes yield reductions on sunflower (Helianthus annuus L.) on several continents, including Australia, Europe, and North America. In the United States, Phomopsis stem canker incidence has increased 16-fold in the Northern Great Plains between 2001 and 2012. Although Diaporthe helianthi was assumed to be the sole causal agent in the United States, a newly described species, D. gulyae, was found to be the primary cause of Phomopsis stem canker in Australia. To determine the identity of Diaporthe spp. causing Phomopsis stem canker in the Northern Great Plains, 275 infected stems were collected between 2010 and 2012. Phylogenetic analyses of sequences of the ribosomal DNA internal transcribed spacer region, elongation factor subunit 1-α, and actin gene regions of representative isolates, in comparison with those of type specimens, confirmed two species (D. helianthi and D. gulyae) in the United States. Differences in aggressiveness between the two species were determined using the stem-wound method in the greenhouse; overall, D. helianthi and D. gulyae did not vary significantly (P ≤ 0.05) in their aggressiveness at 10 and 14 days after inoculation. These findings indicate that both Diaporthe spp. have emerged as sunflower pathogens in the United States, and have implications on the management of this disease.