Articles de revues : « Spot blotch »

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Zanão Júnior, Luiz Antônio, Renildes Lúcio Ferreira Fontes, Paulo Henrique Moreira Coelho, Gaspar Henrique Korndörfer et Laércio Zambolim. « Soil-applied silicon decreases severity of wheat spot blotch on silicon-deficient soils ». Revista Brasileira de Ciência do Solo 34, n^o 2 (avril 2010) : 401–8. http://dx.doi.org/10.1590/s0100-06832010000200013.

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Spot bloth caused by Bipolaris sorokiniana is an important wheat desease mainly in hot and humid regions. The aim of this study was to evaluate the response of wheat to different sources and modes of Si application, as related to the severity of wheat spot blotch and plant growth, in two Si-deficient Latosols (Oxisols). An greenhouse experiment was arranged in a 2 x 5 factorial completely randomized design, with eight replications. The treatments consisted of two soils (Yellow Latosol and Red Latosol) and five Si supply modes (no Si application; Si applied as calcium silicate and monosilicic acid to the soil; and Si applied as potassium silicate or monosilicic acid to wheat leaves). No significant differences were observed between the two soils. When Si was applied to the soil, regardless the Si source, the disease incubation period, the shoot dry matter yield and the Si content in leaves were greater. Additionally, the final spot blotch severity was lower and the area under the spot blotch disease progress curve and the leaf insertion angle in the plant were smaller. Results of Si foliar application were similar to those observed in the control plants.

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Jamil, Muhammad, Aamir Ali, Alvina Gul, Abdul Ghafoor, Amir M. H. Ibrahim et Abdul Mujeeb-Kazi. « Genome-Wide Association Studies for Spot Blotch (Cochliobolus sativus) Resistance in Bread Wheat Using Genotyping-by-Sequencing ». Phytopathology® 108, n^o 11 (novembre 2018) : 1307–14. http://dx.doi.org/10.1094/phyto-02-18-0047-r.

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Spot blotch is a severe biotic menace of wheat caused by Cochliobolus sativus (syn. Bipolaris sorokiniana). Spot blotch is liable to major yield losses in warm humid regions. A genome-wide association study using genotyping-by-sequencing (GBS) markers was conducted to identify genomic regions associated with spot blotch resistance in a diversity panel of 159 spring wheat genotypes. In total, 87,096 GBS markers covering the whole genome, with an average polymorphism information content value of 0.276, were applied. Linkage disequilibrium (LD) analysis indicated that the LD decay extent was approximately 100 Mbp. The panel was evaluated for disease severity (DS) and area under disease progress curve (AUDPC) for 2 years. In total, 24 marker-trait associations (MTA) were identified for DS and AUDPC of spot blotch, with 11 on chromosome 5B, 3 on 3A, 2 on 6B, and 1 each on 1A, 2A, 1D, 2D, 4B, 5A, 7A, and 7B. A marker on chromosome 7B significantly explained 14% of the phenotypic variation of spot blotch severity as well as 11% of AUDPC. Five markers—three on chromosome 5B, one on 3A, and one on 7B—were associated with both DS and AUDPC with R2 ranging from 8 to 12%. Significant MTA can be utilized to develop wheat germplasm with resistance to spot blotch.

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Tembo, Batiseba, Julia Sibiya, Pangirayi Tongoona et Rob Melis. « Genetic Effects of Resistance to Spot Blotch in Selected Wheat Genotypes ». Journal of Plant Breeding and Genetics 6, n^o 1 (25 avril 2018) : 33–38. http://dx.doi.org/10.33687/pbg.006.01.2540.

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Spot blotch disease of wheat (Triticum aestivum L.) caused by Bipolaris sorokiniana (Sacc) Shoemaker causes significant yield and quality losses in warm and humid agro-ecologies of the world. Breeding for resistance is considered to be the most economical and sustainable approach of controlling the disease. The objective of this study was to determine the genetic effect influencing inheritance of resistance to spot blotch in selected wheat genotypes using generation mean analysis to devise a resistance breeding strategy. Populations involving six generations (P1, P2, F1, F2, BCP1 and BCP2) were developed comprising two selected parental lines, i.e., Loerrie II and 19HRWSN6. Test materials were field evaluated for resistance to spot blotch during the 2014/15 cropping season in Zambia. Additive genetic effects were significant and accounted for 94.79% of the total genetic variation for spot blotch resistance in wheat. Dominance and epistatic effects were not detected. The predominance of additive genetic effects suggests that recurrent selection strategy could boost spot blotch resistance in these population to develop pure line wheat cultivars.

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Jalli, Marja, Janne Kaseva, Björn Andersson, Andrea Ficke, Lise Nistrup-Jørgensen, Antanas Ronis, Timo Kaukoranta, Jens-Erik Ørum et Annika Djurle. « Yield increases due to fungicide control of leaf blotch diseases in wheat and barley as a basis for IPM decision-making in the Nordic-Baltic region ». European Journal of Plant Pathology 158, n^o 2 (28 juillet 2020) : 315–33. http://dx.doi.org/10.1007/s10658-020-02075-w.

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Abstract Fungal plant diseases driven by weather factors are common in European wheat and barley crops. Among these, septoria tritici blotch (Zymoseptoria tritici), tan spot (Pyrenophora tritici-repentis), and stagonospora nodorum blotch (Parastagonospora nodorum) are common in the Nordic-Baltic region at variable incidence and severity both in spring and winter wheat fields. In spring barley, net blotch (Pyrenophora teres), scald (Rhynchosporium graminicola, syn. Rhynchosporium commune) and ramularia leaf spot (Ramularia collo-cygni) are common yield limiting foliar diseases. We analysed data from 449 field trials from 2007 to 2017 in wheat and barley crops in the Nordic-Baltic region and explored the differences in severity of leaf blotch diseases between countries and years, and the impact of the diseases on yield. In the experiments, septoria tritici blotch dominated in winter wheat in Denmark and southern Sweden; while in Lithuania, both septoria tritici blotch and tan spot were common. In spring wheat, stagonospora nodorum blotch dominated in Norway and tan spot in Finland. Net blotch and ramularia leaf blotch were the most severe barley diseases over large areas, while scald occurred more locally and had less yield impact in all countries. Leaf blotch diseases, with severity >50% at DC 73–77, caused an average yield loss of 1072 kg/ha in winter wheat and 1114 kg/ha in spring barley across all countries over 5 years. These data verify a large regional and yearly variation in disease severity, distribution and impact on yield, emphasizing the need to adapt fungicide applications to the actual need based on locally adapted risk assessment systems.

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Harteveld, D. O. C., O. A. Akinsanmi, K. Chandra et A. Drenth. « Timing of Infection and Development of Alternaria Diseases in the Canopy of Apple Trees ». Plant Disease 98, n^o 3 (mars 2014) : 401–8. http://dx.doi.org/10.1094/pdis-06-13-0676-re.

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Alternaria leaf blotch and fruit spot of apple caused by Alternaria spp. cause annual losses to the Australian apple industry. Erratic control using protectant fungicides is often experienced and may be due to the lack of understanding of the timing of infection and epidemiology of the diseases. We found that Alternaria leaf blotch infection began about 20 days after bloom (DAB) and the highest disease incidence occurred from 70 to 110 DAB. Alternaria fruit spot infection occurred about 100 DAB in the orchard. Fruit inoculations in planta showed that there was no specific susceptible stage of fruit. Leaves and fruit in the lower canopy of trees showed higher levels of leaf blotch and fruit spot incidence than those in the upper canopy and the incidence of leaf blotch in shoot leaves was higher than in spur leaves. Temperature, relative humidity, and rainfall affected leaf blotch and fruit spot incidence. The gained knowledge on the timing of infection and development of disease may aid in the development of more effective disease management strategies.

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Leng, Yueqiang, Rui Wang, Shaukat Ali, Mingxia Zhao et Shaobin Zhong. « Sources and Genetics of Spot Blotch Resistance to a New Pathotype of Cochliobolus sativus in the USDA National Small Grains Collection ». Plant Disease 100, n^o 10 (octobre 2016) : 1988–93. http://dx.doi.org/10.1094/pdis-02-16-0152-re.

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Spot blotch, caused by Cochliobolus sativus, is one of the important barley diseases in the northern Great Plains of the United States and the Prairie Provinces of Canada. The disease has been under control for almost five decades due to the use of durable spot blotch resistance derived from the barley line ND B112. However, the emergence of isolate ND4008 with virulence on ND B112 prompted us to identify new sources of resistance to this new pathotype. In this study, we screened 2,062 barley accessions from the United States Department of Agriculture National Small Grains Collection for spot blotch resistance, and identified 40 barley accessions exhibiting a high level of resistance to isolate ND4008 at the seedling stage. In all, 24 of the barley accessions with seedling resistance also exhibited moderate to high adult plant resistance to ND4008 in greenhouse tests. Seven of the ND4008-resistant barley accessions showed seedling resistance to two other pathotypes (1 and 2) of the pathogen. Genetic study of resistant barley accessions PI 235186, PI 592275, and PI 643242 indicated that a single major dominant gene controls spot blotch resistance to ND4008 in each of these three accessions. These resistant sources are useful for developing barley cultivars with spot blotch resistance to all pathotypes of C. sativus.

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Navathe, Sudhir, Ajeet Kumar Pandey, Sandeep Sharma, Ramesh Chand, Vinod Kumar Mishra, Dinesh Kumar, Sarika Jaiswal et al. « New Genomic Regions Identified for Resistance to Spot Blotch and Terminal Heat Stress in an Interspecific Population of Triticum aestivum and T. spelta ». Plants 11, n^o 21 (5 novembre 2022) : 2987. http://dx.doi.org/10.3390/plants11212987.

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Wheat is one of the most widely grown and consumed food crops in the world. Spot blotch and terminal heat stress are the two significant constraints mainly in the Indo–Gangetic plains of South Asia. The study was undertaken using 185 recombinant lines (RILs) derived from the interspecific hybridization of ‘Triticum aestivum (HUW234) × T. spelta (H+26)’ to reveal genomic regions associated with tolerance to combined stress to spot blotch and terminal heat. Different physiological (NDVI, canopy temperature, leaf chlorophyll) and grain traits (TGW, grain size) were observed under stressed (spot blotch, terminal heat) and non-stressed environments. The mean maturity duration of RILs under combined stress was reduced by 12 days, whereas the normalized difference vegetation index (NDVI) was 46.03%. Similarly, the grain size was depleted under combined stress by 32.23% and thousand kernel weight (TKW) by 27.56% due to spot blotch and terminal heat stress, respectively. The genetic analysis using 6734 SNP markers identified 37 significant loci for the area under the disease progress curve (AUDPC) and NDVI. The genome-wide functional annotation of the SNP markers revealed gene functions such as plant chitinases, NB-ARC and NBS-LRR, and the peroxidase superfamily Cytochrome P450 have a positive role in the resistance through a hypersensitive response. Zinc finger domains, cysteine protease coding gene, F-box protein, ubiquitin, and associated proteins, play a substantial role in the combined stress of spot blotch and terminal heat in bread wheat, according to genomic domains ascribed to them. The study also highlights T. speltoides as a source of resistance to spot blotch and terminal heat tolerance.

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BERG, C. G. J. VAN DEN, et B. G. ROSSNAGEL. « EFFECT OF TILT ON SEVERITY OF SPOT-TYPE NET BLOTCH, GRAIN YIELD AND YIELD COMPONENTS IN BARLEY ». Canadian Journal of Plant Science 70, n^o 2 (1 avril 1990) : 473–80. http://dx.doi.org/10.4141/cjps90-055.

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Spot-type net blotch, incited by Pyrenophora teres f. maculata has become widespread in Saskatchewan. This study was conducted to evaluate the effect of the fungicide Tilt (propiconazole) on the severity of spot-type net blotch, grain yield and yield components in spring barley. The susceptible cultivar Elrose was subjected to five schedules of foliar application of Tilt at Medstead, Shellbrook and Saskatoon, Saskatchewan in 1985 and 1986. The moderately susceptible cultivar Argyle was included in the experiments conducted in 1986. Results show that Tilt controlled spot-type net blotch in Elrose. However, the effective period was limited. A single application did not control spot-type net blotch in cases with rapid disease development. Application of Tilt at Zadoks growth stages 31 and 49 would be required to provide reliable control in a susceptible cultivar. Control of spot-type net blotch increased grain yield. A single application of Tilt increased grain yield up to 23% over the untreated control. In most cases, a double application of Tilt did not increase grain yield over a timely single application. Increased grain yield was associated with increased kernel weight. The correlation coefficient between grain yield and kernel weight ranged from 0.82 to 0.88. Tilt had no effect on a healthy crop of Elrose and the moderately susceptible cultivar Argyle.Key words: Pyrenophora teres f. maculata, Hordeum vulgare L., propiconazole, barley

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Tyryshkin, L. G., et N. A. Tyryshkina. « Resistance to Diseases in Wheat Collection Samples and Somaclonal Variants ». Czech Journal of Genetics and Plant Breeding 39, No. 1 (23 novembre 2011) : 21–23. http://dx.doi.org/10.17221/3717-cjgpb.

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More than 2000 wheat collection samples were studied for seedling resistance to 4 diseases. Noncoincidence of results obtained after inoculation of leaf segments placed on water solution of benzimidazole (60 ppm) and intact plants was found for 3 foliar diseases (leaf rust – Puccinia recondita, dark brown leaf spot blotch – Bipolaris sorokiniana and septoria glume blotch – Septoria nodorum). Sixty-three entries were resistant to leaf rust; 26 of them have gene for resistance Lr26 (non-effective under field condition), 25 – gene Lr24, 4 – gene Lr19, 8 – gene Lr9 and 2 – gene Lr41. Samples 181-5, Fielder, Butte 66, Raj 1972 and Soisson were moderately resistant to spot blotch; 181-5 – to common root rot and Moking and MN 81330 – to glume blotch. Very high level of partial resistance to 3 diseases was found in late generations of somaclonal lines of weakly and moderately resistant initial genotypes: to leaf rust in lines of cv. Spica, to leaf spot blotch – in lines of 181-5, to common root rot – in that of 181-5 and cv. Vera; moderate resistance to glume blotch was identified in lines of cv. Spica.   

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Neupane, R. B., R. C. Sharma, E. Duveiller, G. Ortiz-Ferrara, B. R. Ojha, U. R. Rosyara, D. Bhandari et M. R. Bhatta. « Major Gene Controls of Field Resistance to Spot Blotch in Wheat Genotypes ‘Milan/Shanghai #7’ and ‘Chirya.3’ ». Plant Disease 91, n^o 6 (juin 2007) : 692–97. http://dx.doi.org/10.1094/pdis-91-6-0692.

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A number of exotic wheat (Triticum aestivum) genotypes resistant to spot blotch caused by Cochliobolus sativus are being used to improve the resistance of commercial cultivars in the warm regions of South Asia. The objective of the present study was to determine the inheritance of field resistance to spot blotch in two resistant (R) wheat genotypes, ‘Chirya.3’ and ‘Milan/Shanghai #7’ (MS#7), which were crossed to a susceptible (S) commercial cultivar, ‘BL1473.’ The two resistant genotypes also were crossed to determine allelic relationships for resistance between them. Spot blotch severity was recorded on the parents and on F1, F2, and F3 progenies. The F1 plants from the two crosses between susceptible and resistant genotypes had low disease severity like the resistant parents, indicating that resistance in Chirya.3 and MS#7 is conditioned by dominant gene action. The F2 plants segregated in 3R:1S ratios, and the F2:3 families showed the ratio of 1R:1S:2S, segregating for R and S, suggesting that resistance in the two resistant parents is conditioned by a single, dominant gene. The F1 plants from the cross between the two resistant genotypes were resistant, whereas their F2 progenies segregated in 15R:1S, suggesting that the resistance genes in MS#7 and Chirya.3 are nonallelic. These simply inherited sources of resistance could be useful for improving spot blotch resistance in the warm regions of South Asia and also may offer useful diversity to breeding programs for developing spot-blotch-resistant wheat cultivars in other regions.

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Mahto, B. N., S. Gurung et Tika B. Adhikari. « Assessing genetic resistance to spot blotch, Stagonospora nodorum blotch and tan spot in wheat from Nepal ». European Journal of Plant Pathology 131, n^o 2 (26 mai 2011) : 249–60. http://dx.doi.org/10.1007/s10658-011-9803-5.

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DOSTALER, D., G. J. PELLETIER et L. COUTURE. « ETUDE DE LA TOLERANCE DE CULTIVARS D’ORGE A LA TACHE HELMINTHOSPORIENNE ». Canadian Journal of Plant Science 67, n^o 1 (1 janvier 1987) : 153–57. http://dx.doi.org/10.4141/cjps87-018.

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This study was conducted to assess tolerance of barley (Hordeum vulgare) cultivars to spot blotch. The barley cultivars Parkland, Bonanza and Laurier inoculated with spores of Bipolaris sorokiniana developed approximately the same level of spot blotch symptoms in the field. Natural disease development was minimal in plots treated with mancozeb; it was intermediate in uninoculated and untreated plots. Reduction of grain yield and grain weight differed with each cultivar. Disease had the most depressing effects on Parkland. Disease severity was highest on Laurier which suffered the least decrease in grain yield and grain weight compared to the checks. Yield and seed weight of Bonanza were not affected by low or moderate disease levels (checks) but were reduced when symptoms were severe (inoculations).Key words: Barley, cultivars, spot blotch, Bipolaris sorokiniana, tolerance, mancozeb

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Fetch, Thomas G., Brian J. Steffenson, Harold E. Bockelman et Darrell M. Wesenberg. « Spring barley accessions with dual spot blotch and net blotch resistance ». Canadian Journal of Plant Pathology 30, n^o 4 (décembre 2008) : 534–42. http://dx.doi.org/10.1080/07060660809507553.

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Legge, W. G., D. R. Metcalfe, A. W. Chiko, J. W. Martens et A. Tekauz. « Reaction of Turkish barley accessions to Canadian barley pathogens ». Canadian Journal of Plant Science 76, n^o 4 (1 octobre 1996) : 927–31. http://dx.doi.org/10.4141/cjps96-155.

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Recent changes in the virulence patterns of Canadian barley pathogens have necessitated the search for new sources of genetic resistance in barley. Evaluation of 176 Turkish barley accessions for disease reaction to barley pathogens prevalent in Canada indicated that this germplasm is a good source of resistance to Septoria passerinii, Rhynchosporium secalis and the spot-form of Pyrenophora teres, but not to Cochliobolus sativus (spot blotch phase), Puccinia graminis tritici, Ustilago nuda or barley stripe mosaic virus. A small number of accessions with resistance to the net-form of P. teres were identified. Key words:Hordeum vulgare, barley, disease resistance, net blotch, scald, speckled leaf blotch

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Kutcher, H. R., K. L. Bailey, B. G. Rossnagel et W. G. Legge. « Identification of RAPD markers for common root rot and spot blotch (Cochliobolus sativus) resistance in barley ». Genome 39, n^o 1 (1 février 1996) : 206–15. http://dx.doi.org/10.1139/g96-027.

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The identification of RAPD markers associated with genes for resistance to Cochliobolus sativus in barley would increase the efficiency of gene manipulation by reducing the number of lines that must be evaluated from a resistant by susceptible cross and by allowing selection during the off season. Two barley crosses consisting of resistant and susceptible parent genotypes ('Virden' × 'Ellice' and Fr926-77 × 'Deuce', both 2 row × 6 row crosses) and more than 140 homozygous progeny lines were rated for their reactions in field nurseries to common root rot and in a controlled environment for spot blotch. Putative RAPD markers were identified using bulked segregant analysis followed by individual progeny line analyses. Polymorphisms associated with disease reaction were detected between bulked segregant samples as differences in the band intensity of DNA fragments. The bulked segregant samples were screened against 186 RAPD primers (decamers) using the polymerase chain reaction. For the cross Fr926-77 × 'Deuce', one RAPD marker was obtained that did not segregate as expected but was associated with both diseases. For the cross 'Virden' × 'Ellice', a single RAPD marker was obtained that did not have the expected segregation ratio but was associated with spot blotch reaction. One RAPD marker linked to 2-rowed and 6-rowed spike locus was obtained in each cross, and both the marker and row type were associated with common root rot and spot blotch reactions. For the cross 'Virden' × 'Ellice', a linkage group consisting of three RAPD markers was associated with common root rot and spot blotch reaction. The genes associated with these markers condition significant levels of resistance to C. sativus and may be used to increase the speed and precision of resistance gene manipulation in barley germplasm. Key words : common root rot, spot blotch, Cochliobolus sativus, molecular markers, barley.

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KUMAR, VISHNU, SUDHEER KUMAR, S. P. SINGH, S. S. VAISH, DEEPSHIKHA DEEPSHIKHA, J. B. KHAN, A. S. KHARUB et G. P. SINGH. « Identification of resistant genotypes and representative environments for spot blotch (Biploris sorokiniana) in barley (Hordeum vulgare) ». Indian Journal of Agricultural Sciences 90, n^o 5 (4 septembre 2020) : 909–13. http://dx.doi.org/10.56093/ijas.v90i5.104358.

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A set of 31 barley genotypes was evaluated at four locations, viz. Kanpur, Pantnagar, Varanasi and Faizabad for two years (2016 and 2017) against spot blotch [Biploris sorokiniana (Sacc.) Shoem.] resistance. The combined analysis of variance revealed significant influence of year (5.64%) and location (18.08%) effects with significant genotypic effects (29.05%). Location-wise, the highest susceptibility was observed at Varanasi (51.61%) followed by Kanpur (19.35%) whereas, the moderately susceptible reactions were obtained at Faizabad (67.74 %) and Kanpur (61.29%) locations. In heritability adjusted GGE biplot analysis, the ratio of (G+G × E)/(E+G+G × E) was estimated as 71.77 % and substantiated usefulness of generated biplots to elucidate resistant and stable genotypes with location discrimination. In AMMI analysis, the initial two principal components (PCs) cumulatively explained 90.7 % of total variation with individual scores of 51.8 % and 38.9 %, respectively. The triangular image of the initial three PCs depicted scattered pattern for disease reaction and varied response for the locations. The weather parameters, viz. maximum temperature, minimum temperature and sunshine hr/day showed strong correlations 0.87**, 0.83** and 0.64* with spot blotch severity. The genotypes, DWRB 180, PL 891 and DWRB 190 were found promising and suggested to be used in future resistance breeding and spot blotch genetic studies. The locations Varanasi and Faizabad were found type 2 discriminative and representative environments for spot blotch.

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MOREIRA, CRISTIANO R., et FLÁVIO C. T. LIMA. « Two new Hyphessobrycon (Characiformes : Characidae) species from Central Amazon basin, Brazil ». Zootaxa 4318, n^o 1 (6 septembre 2017) : 123. http://dx.doi.org/10.11646/zootaxa.4318.1.5.

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Two new species of Hyphessobrycon, H. ericae and H. wosiackii, are described from the Amazon basin, Brazil. Both new species are distinguished from congeners by the coloration, composed by one humeral blotch merging with an anterior dark band restricted to the anterior portion of the body and the presence of a caudal peduncle blotch. Hyphessobrycon ericae is distinguished from H. wosiackii by presenting a humeral spot vertically elongated, with an overall appearance of an arrow, instead of an anteriorly rounded humeral spot.

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Smurova, S. G., et L. A. Mikhailova. « Sources of resistance to wheat spot blotch ». Russian Agricultural Sciences 33, n^o 6 (décembre 2007) : 378–80. http://dx.doi.org/10.3103/s1068367407060092.

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Raheeba Tun Nisa, Altaf Ahmad Wani, et Rameesa Rashid. « Chemical Management of Alternaria leaf and fruit spot of apple ». International Journal of Current Microbiology and Applied Sciences 10, n^o 12 (10 décembre 2021) : 521–26. http://dx.doi.org/10.20546/ijcmas.2021.1012.057.

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In Jammu and Kashmir, a number of diseases like scab, Alternaria leaf blotch, Marsonena, sooty blotch, fly-speck and a number of post-harvest diseases pose a major threat to the apple industry. The occurrence of Alternaria leaf blotch in J&K was reported and the disease is prevalent in almost all the apple growing districts of Kashmir valley. Alternaria leaf blotch was considered a disease of minor importance in comparison to apple scab. However, the disease resulted in epidemic during summer of 2013, and about 40-60 per cent yield loss was reported. This epidemic was attributed to climate change ( high temperature coupled with prolonged rains), absence of disease forecasting system in the valley and also to the fact that currently used fungicides do not provide satisfactory level of disease control. When overwintering mycelium forms conidia and infects fresh budding apple leaves in the spring, the infection begins. After 90 days after flowering, a rise in temperature combined with significant rainfall and relative humidity enhances secondary infection in leaves and fruits. For disease control, a variety of techniques are available, including cultural, chemical, resistance, and biological approaches. We'll go through the disease's cause, symptoms, and treatment options here.

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Gultyaeva, Elena I., Ekaterina R. Shreyder, Igor’ Yu Kushnirenko, Ekaterina L. Shaydayuk et Nadezhda M. Kovalenko. « Evaluation of advanced bread spring wheat lines for field and seedling resistance to foliar pathogens ». BIO Web of Conferences 23 (2020) : 01005. http://dx.doi.org/10.1051/bioconf/20202301005.

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Foliar diseases (rusts and blotches) significantly limit the yield of spring wheat in the Southern Urals. The aim of the research was a comprehensive assessment of 17 promising lines of bread spring wheat, created at the Chelyabinsk Research Institute of Agriculture, for disease resistance and their identification of Lr genes. Resistance to leaf and stem rusts, Paraganospora nodorum leaf blotch and tan spot was studied in the field and laboratory conditions. All studied lines were characterized by high level of resistance to leaf and stem rusts in the seedling and adult plant stages. A wide representation of the LrSp gene (individually or in combination with noneffective genes Lr1, Lr3, Lr10, Lr9), and genes Lr24/Sr24, Lr19/Sr25 and effective combinations of seedling (Lr9 + Lr26/Sr31) and adult plant (Lr34/Sr57 and Lr21) resistance genes was revealed using molecular markers. Multiple resistance to rust and blotches (Paraganospora nodorum leaf blotch and tan spot) was detected in the Ferr. 26768 line. Molecular analysis showed the presence of adult plant resistance genes Lr34/Sr57 + Lr21 in combination with Lr10 gene. Along with diseases resistance, Ferr. 26768 line is promising in terms of a set of economically valuable attributes (lodging resistance, grain quality, yield).

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Navathe, Sudhir, Punam Singh Yadav, Ramesh Chand, Vinod Kumar Mishra, Neeraj Kumar Vasistha, Prabina Kumar Meher, Arun Kumar Joshi et Pushpendra Kumar Gupta. « ToxA–Tsn1 Interaction for Spot Blotch Susceptibility in Indian Wheat : An Example of Inverse Gene-for-Gene Relationship ». Plant Disease 104, n^o 1 (janvier 2020) : 71–81. http://dx.doi.org/10.1094/pdis-05-19-1066-re.

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The ToxA–Tsn1 system is an example of an inverse gene-for-gene relationship. The gene ToxA encodes a host-selective toxin (HST) which functions as a necrotrophic effector and is often responsible for the virulence of the pathogen. The genomes of several fungal pathogens (e.g., Pyrenophora tritici-repentis, Parastagonospora nodorum, and Bipolaris sorokiniana) have been shown to carry the ToxA gene. Tsn1 is a sensitivity gene in the host, whose presence generally helps a ToxA-positive pathogen to cause spot blotch in wheat. Cultivars lacking Tsn1 are generally resistant to spot blotch; this resistance is attributed to a number of other known genes which impart resistance in the absence of Tsn1. In the present study, 110 isolates of B. sorokiniana strains, collected from the ME5A and ME4C megaenvironments of India, were screened for the presence of the ToxA gene; 77 (70%) were found to be ToxA positive. Similarly, 220 Indian wheat cultivars were screened for the presence of the Tsn1 gene; 81 (36.8%) were found to be Tsn1 positive. When 20 wheat cultivars (11 with Tsn1 and 9 with tsn1) were inoculated with ToxA-positive isolates, seedlings of only those carrying the Tsn1 allele (not tsn1) developed necrotic spots surrounded by a chlorotic halo. No such distinction between Tsn1 and tsn1 carriers was observed when adult plants were inoculated. This study suggests that the absence of Tsn1 facilitated resistance against spot blotch of wheat. Therefore, the selection of wheat genotypes for the absence of the Tsn1 allele can improve resistance to spot blotch.

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De Wolf, E. D., et L. J. Francl. « Neural Network Classification of Tan Spot and Stagonospora Blotch Infection Periods in a Wheat Field Environment ». Phytopathology® 90, n^o 2 (février 2000) : 108–13. http://dx.doi.org/10.1094/phyto.2000.90.2.108.

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Tan spot and Stagonospora blotch of hard red spring wheat served as a model system for evaluating disease forecasts by artificial neural networks. Pathogen infection periods on susceptible wheat plants were measured in the field from 1993 to 1998, and incidence data were merged with 24-h summaries of accumulated growing degree days, temperature, relative humidity, precipitation, and leaf wetness duration. The resulting data set of 202 discrete periods was randomly assigned to 10 modeldevelopment or -validation (n = 50) data sets. Backpropagation neural networks, general regression neural networks, logistic regression, and parametric and nonparametric methods of discriminant analysis were chosen for comparison. Mean validation classification of tan spot incidence was between 71% for logistic regression and 76% for backpropagation models. No significant difference was found between methods of modeling tan spot infection periods. Mean validation prediction accuracy of Stagonospora blotch incidence was 86 and 81% for backpropagation and logistic regression, respectively. Prediction accuracies of other modeling methods were ≤78% and were significantly different (P = 0.01) from backpropagation, but not logistic regression, results. The best backpropagation models of tan spot and Stagonospora blotch incidences correctly classified 82 and 84% of validation cases, respectively. High classification accuracy and consistently good performance demonstrate the applicability of neural network technology to plant disease forecasting.

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Matkovska, M. « Influence of fertilization and fungicide on increasing the winter barley productivity ». Agrobìologìâ, n^o 1(157) (25 mai 2020) : 104–10. http://dx.doi.org/10.33245/2310-9270-2020-157-1-104-110.

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The article represents the results of research for 2016–2018 in the condition of Western Forest-Steppe of Ukraine. The yield of winter barley obtained under various fungicide treatment and three diff erent fertilization dose rates of (N40P30K40, N80P60K80, N120P90K120) was compared in the study The influence of mineral fertilizers on the diseases development was studied along with fungicides application effi ciency for the following diseases of Wintmalt variety of winter barley: net blotch, powdery mildew, and spot blotch. Three major diseases were observed in barley crops during the research years: net blotch, powdery mildew and spot blotch. It has been established that increasing the level of fertilization contributes to the increase of disease development in barley crops. Thus, the highest level of net blotch (51.7 %), spot blotch (15.4 %) and powdery mildew (17.5 %) was observed on the variant of N120P90K120. High effi ciency of the studied fungicides was established. The highest technical effi cacy of the preparations was obtained on the variant of Systiva 1,5 l/t + Adexar Plus 1,0 l/ha in the stage of the fl ag leaf. The results of the studies showed that the highest yield (9.27 t/ha) of the Wintmalt variety of winter barley under the studied conditions was obtained on the variant of complete mineral fertilization N120P90K120 and the treatment of fungicide plant protection by Systiva 1.5 l/t (BBCH 00) + Adexar Plus (BBCH 39) 1.0 l/ha. The fungicide protection of Systiva applied to the seeds along with the pre-sowing treatment, ensured a yield increase of 0.64 t/ha, 0.68 t/ha and 0.77 t/ha on the N40P30K40, N80P60K80, N120P90K120 respectively. The highest yield increase compared to the control was obtained on the Systiva 1.5 l/t (BBCH 00) + Adexar Plus (BBCH 39) 1.31–1.69 t/ha depending on the dose rates of fertilization. Fungicide protection is recommended to apply to all the studied fertilizers dose rates, but the highest yield increase from the fungicides was obtained on N 120P90K120. Key words: winter barley, fungicide, Systiva, Abacus, Adexar Plus, disease, fertilizers, yield.

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Kaur, Amrinder. « Characterization of Barley Entries for Spot Blotch Resistance ». International Journal of Current Microbiology and Applied Sciences 9, n^o 10 (10 octobre 2020) : 161–71. http://dx.doi.org/10.20546/ijcmas.2020.910.021.

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Domiciano, Gisele Pereira, Fabrício Avila Rodrigues, Francisco Xavier Ribeiro Vale, Maria Santina Xavier Filha, Wiler Ribas Moreira, Camila Cristina Lage Andrade et Sandra Cerqueira Pereira. « Wheat Resistance to Spot Blotch Potentiated by Silicon ». Journal of Phytopathology 158, n^o 5 (mai 2010) : 334–43. http://dx.doi.org/10.1111/j.1439-0434.2009.01623.x.

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DICKENS, J. S. W., et R. T. A. COOK. « Japanese pear black spot and apple alternaria blotch ». EPPO Bulletin 25, n^o 4 (décembre 1995) : 651–59. http://dx.doi.org/10.1111/j.1365-2338.1995.tb01117.x.

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Singh, Tejveer, Vinod Kumar Mishra et Ramesh Chand. « Inheritance of Spot Blotch Disease Components in Barley ». Journal of Crop Improvement 30, n^o 5 (8 juillet 2016) : 541–51. http://dx.doi.org/10.1080/15427528.2016.1193782.

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ENTZ, M. H., C. G. J. VAN DEN BERG, E. H. STOBBE, B. G. ROSSNAGEL, G. P. LAFOND et H. M. AUSTENSON. « EFFECT OF LATE-SEASON FUNGICIDE APPLICATION ON GRAIN YIELD AND SEED SIZE DISTRIBUTION IN WHEAT AND BARLEY ». Canadian Journal of Plant Science 70, n^o 3 (1 juillet 1990) : 699–706. http://dx.doi.org/10.4141/cjps90-086.

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Field trials were conducted to determine the effect of foliar fungicides on grain yield, kernel size and seed size distribution in wheat and barley. Tilt (propiconazole) was applied at 125 g a.i. ha−1 between Zadoks growth stages 49 and 59. Following harvest, seed samples from treated and untreated plots were stratified into different size classes. In barley trials, net blotch was the most prevalent leaf disease while in wheat trials, tan spot, leaf rust and Septoria leaf spot were most prevalent. Under high levels of disease, Tilt reduced the level of disease and significantly increased grain yield and the amount of large kernels in both wheat and barley. Under low levels of disease, Tilt rarely increased grain yield, but frequently increased the amount of large kernels. In barley, the increase in amount of seed in the larger size classes across all sites was correlated (P < 0.05) with reduction in net blotch severity. No significant effect of Tilt on germination at 5 °C was observed for any of the wheat cultivars considered in this study. Increases in the yield of large kernels indicate that late season applications of fungicide may be useful in pedigreed seed production, where large kernels are desired.Key words: Seed crops, kernel weight, seed vigor, tan spot, Septoria, net blotch

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Cabrefiga, Jordi, Maria Victoria Salomon et Pere Vilardell. « Improvement of Alternaria Leaf Blotch and Fruit Spot of Apple Control through the Management of Primary Inoculum ». Microorganisms 11, n^o 1 (30 décembre 2022) : 101. http://dx.doi.org/10.3390/microorganisms11010101.

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Alternaria spp. is the causal agent of apple leaf blotch and fruit spot, diseases of recent appearance in Spain. The overwinter inoculum of Alternaria spp. is the source of primary infections in apple, thus the aim of this work was to optimize the control of infection through two environmentally friendly inoculum-management strategies, the removal of winter fallen leaves and the treatment of leaves with the biological agent Trichoderma asperellum to inhibit or prevent inoculum development in commercial orchards. The results of commercial orchard trials showed that leaf aspiration and application of T. asperellum on the ground have efficacy to reduce fruit spot between 50 and 80% and leaf blotch of between 30 and 40% depending on the year. The efficacies on the reduction of leaf blotch were slightly lower than of fruit spot. Disease reduction has been related to a reduction of total spores released during the season. Results of dynamics of spore release indicate that factors influencing spore release were rainfall and temperature. In conclusion, the use of environmentally friendly strategies combined with standard fungicides, and with monitoring environmental conditions, might allow a reduction in the number of phytosanitary applications, thus achieving the goal of reducing their use.

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Bankina, B., J. Kaņeps, M. Darguža et G. Bimšteine. « Development of wheat leaf blotches depending on soil tillage system ». IOP Conference Series : Earth and Environmental Science 1096, n^o 1 (1 octobre 2022) : 012002. http://dx.doi.org/10.1088/1755-1315/1096/1/012002.

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Abstract Conservative soil tillage is considered as the main tool to preserve soil fertility, to reduce gas emissions, and to save financial and labour resources. However, majority of researchers have found that different systems of reduced soil tillage increase the occurrence of slugs, weeds and diseases, including wheat diseases. The aim of the present study was to determine the impact of reduced soil tillage on the severity of winter wheat leaf blotches. The influence of different soil tillage systems and crop rotation on the severity of winter wheat disease was evaluated in a two-factorial experiment: A – soil tillage system (A1 – traditional soil tillage with ploughing at the depth of 22–24 cm); A2 – reduced soil tillage with disc harrowing up to the depth of 10 cm); and B – different crop rotations (B1 – continuous winter wheat; B2 – winter wheat and oilseed rape were grown; B3 – crop rotation). The severity of diseases was determined approximately every 10 days during the whole vegetation season, the total disease impact was estimated by calculating the area under the disease progress curve. Tan spot, caused by Pyrenophora tritici-repentis and Septoria tritici blotch, caused by Zymoseptoria tritici dominated in trials during the entire research period. Soil tillage is the most important factor promoting the development of tan spot, continuous wheat sowings also increased the severity of tan spot. The development of Septoria tritici blotch did not depend on the agronomic practice applied.

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Choo, Thin Meiw, Allen G. Xue et Richard A. Martin. « AAC Vitality barley ». Canadian Journal of Plant Science 96, n^o 3 (1 juin 2016) : 367–70. http://dx.doi.org/10.1139/cjps-2015-0218.

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AAC Vitality is a six-row spring feed barley (Hordeum vulgare L.) cultivar developed by the Eastern Cereal and Oilseed Research Centre, Agriculture and Agri-Food Canada. AAC Vitality had high grain yield, good resistance to lodging, and good resistance to straw break. It was late in heading and maturity. Its seed color was bright. AAC Vitality was moderately resistant to net blotch and spot blotch. AAC Vitality performs well in Ontario.

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Kandel, Khagendra, Dilli Dhakal, Harish Giri, Sushil Basnet, Utsav Koirala et Narayan Dhakal. « Response of different wheat varieties to Bipolaris sorokiniana at seedling stage under laboratory condition ». Journal of Agriculture and Natural Resources 3, n^o 1 (7 janvier 2020) : 170–79. http://dx.doi.org/10.3126/janr.v3i1.27155.

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Spot blotch (Bipolaris sorokiniana) is a major disease of wheat in warm, humid wheat-growing regions. The aim of present study was to evaluate the infection symptomology and disease severity to different wheat varieties under laboratory condition. A total of ten wheat genotypes including RR-21 (a susceptible check) and Aditya (a resistant check), were evaluated for seedling stage resistance to spot blotch disease through artificial inoculation under laboratory condition at Gokuleswor, Baitadi during 2018. Based on disease severity and area under disease progress curve (AUDPC), Aditya was found resistant and RR-21 was found susceptible The tested genotypes were categorized on the basis of total AUDPC value, where Banganga, BL4341, BL4407 and local genotype were moderately resistant, BL-4406, NL-1190, NL-297 and NL-971 were found moderately susceptible to spot blot at seedling stage. The susceptible check, RR-21 had the highest disease severity (44%) as well as mean AUDPC value (51.38).

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V. Rozanova, Irina, Nina M. Lashina, Vadim M. Efimov, Olga S. Afanasenko et Elena K. Khlestkina. « The In-Silico Development of DNA Markers for Breeding of Spring Barley Varieties That Are Resistant to Spot Blotch in Russia ». Agriculture 10, n^o 11 (28 octobre 2020) : 505. http://dx.doi.org/10.3390/agriculture10110505.

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The fungal pathogen Cochliobolus sativus Drechs. Ex Dastur, anamorph Bipolaris sorokiniana (Sacc.) Shoemaker is one of the most common barley pathogens worldwide and causes spot blotch and root rot in barley. Spot blotch is considered to be the major biotic stress hampering the commercial production of barley. During high disease severity, which occurs in the northwestern region of Russia once every three to four years, yield losses for barley may reach 40%. An increase in common root rot severity results in yield losses that can reach 80%. The goal of the current study was to identify significant markers that can be employed as diagnostic DNA markers to breed C. sativus pathogen-resistant varieties of barley. In 94 spring barley cultivars and lines, the resistance of seedlings and adult plants to the impact of C. sativus on their leaves and roots was investigated. Five genomic regions associated with resistance to Spot blotch were identified (on chromosome 1H (50–61.2 cM), 2H (68.7–69.68 cM), 3H (18.72–26.18 cM), 7H (7.52–15.44 cM)). No significant loci were determined to be associated with root rot. According to obtained data, 11 significant SNPs were converted into KASP markers and 6 markers located on chromosome 3H were determined to possess good accuracy and the potential to be employed in marker-assisted selection.

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Rosyara, U., S. Subedi, R. Sharma et E. Duveiller. « Spot blotch and terminal heat stress tolerance in south Asian spring wheat genotypes ». Acta Agronomica Hungarica 57, n^o 4 (1 décembre 2009) : 425–35. http://dx.doi.org/10.1556/aagr.57.2009.4.5.

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Terminal heat stress and spot blotch disease (caused by Cochliobolus sativus ) are the most important stresses responsible for significant yield losses every year in warm South Asian plains. Both of these stresses are very severe in late planted wheat, which is common in rice-wheat and rice-rice-wheat cropping systems. The development of genotypes tolerant to both stresses might be very useful for increasing yield and reducing yield losses. Information is limited on how different genotypes respond to both stresses (individually and combined) and on the degree of tolerance present in South Asian wheat genotypes. The study was done to evaluate the tolerance of South Asian wheat genotypes to both stresses by comparing the stress factor susceptibility index (SFSI). Eleven diverse South Asian genotypes were evaluated under spot blotch stress (non-fungicide protected plots), heat stress (late planted and fungicide protected), both stresses (non-fungicide protected and late planted) and normal planting situations (fungicide protected and normal season planted) at Rampur, Chitwan, Nepal. Both stresses reduced the grain yield and thousand-kernel weight (TKW), but not other yield components, including grains/spike and spikelets/spike. Genotypes BL 1473, Gautam and NL971 were moderately to highly tolerant to both types of stress. Generally genotypes that are tolerant or resistant to spot blotch also showed tolerance to heat stress, suggesting a common physiological mechanism to combat both stresses in tolerant genotypes.

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Bankina, Biruta, Gunita Bimšteine, Irina Arhipova, Jānis Kaņeps et Madara Darguža. « Impact of Crop Rotation and Soil Tillage on the Severity of Winter Wheat Leaf Blotches ». Rural Sustainability Research 45, n^o 340 (1 août 2021) : 21–27. http://dx.doi.org/10.2478/plua-2021-0004.

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Abstract Reduced tillage is considered as one of the main tools to save biological diversity; however, it increases pressure of diseases, including wheat leaf blotches. The aim of present study was to clarify the impact of reduced soil tillage on the development of winter wheat leaf blotches in different schemes of crop rotation. The impact of different growing technologies on the severity of winter wheat disease was evaluated in a two-factorial experiment: A – soil tillage system, and B – different combinations of wheat pre-pre-crop and pre-crop (wheat, oilseed rape, barley and faba beans). Diseases were assessed every 10 days approximately and total impact of diseases was evaluated by calculating AUDPC (Area under Diseases Progress Curve). Tan spot, caused by Pyrenophora tritici-repentis was dominated disease over the long period, regardless of meteorological conditions. Development of Septoria leaf blotch was not influenced by neither crop rotation nor soil tillage. The level of tan spot was essentially higher after wheat, regardless of the pre-pre-crop. Reduced soil tillage promoted severity of tan spot. Ploughing mitigated effect of previous crops and differences in tan spot level were insignificant. Despite many positive effects of conservation tillage, increasing of fungicide treatment could be necessary, in conditions, when the tan spot is most devastating and widespread wheat disease.

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Damicone, J. P., C. C. Holbrook, D. L. Smith, H. A. Melouk et K. D. Chamberlin. « Reaction of the Core Collection of Peanut Germplasm to Sclerotinia Blight and Pepper Spot1 ». Peanut Science 37, n^o 1 (1 janvier 2010) : 1–11. http://dx.doi.org/10.3146/ps09-001.1.

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Abstract In 2001, entries from the peanut core collection, a subset of the USDA peanut germplasm collection, were planted in non-replicated plots in a field with a history of Sclerotinia blight caused by Sclerotinia minor. Variability existed among entries for reaction to Sclerotinia blight. Of the 744 entries evaluated, 11% had no disease, nearly 30% had <10% disease incidence, and only 21% had 50% disease incidence or more. Most of the resistant entries had an upright growth habit and were in early and mid-maturity groups. Many of the early maturing entries were susceptible to the foliar disease pepper spot which occurred throughout the study. Entries were selected for further evaluation in replicated plots based on a nil to low (<10%) incidence of Sclerotinia blight, adaptation and/or vigor, and other desirable characteristics such as an intermediate to prostrate growth habit and pepper spot resistance. Selected entries were retested in both 2002 and 2003 (n = 62) and compared to resistant (Tamspan 90), moderately resistant (Tamrun 96), and susceptible (Okrun) reference cultivars. Most entries (55 in 2001 and 46 in 2003) had disease incidence less than Tamrun 96 and similar to Tamspan 90. In 2003 when disease incidence was highest, all 46 entries with resistant reactions similar to that of Tamspan 90 had erect plant growth habits except for entries 208 and 582 which were prostrate, and entries 273, 128, and 804 which were intermediate. Resistance to Sclerotinia blight and yield similar to Tamspan 90, plant habit, and/or reactions to pepper spot and web blotch were used to select the best entries. Entries 208, 128, 804, 582, and 273 combined resistance to Sclerotinia blight, pepper spot, and web blotch with less than erect growth habits. Entry 103 had good Sclerotinia blight resistance and yield, but an upright growth habit. Entry 92 had an upright growth habit and low yield, but good Sclerotinia blight resistance. Entries 92 and 103 had upright growth habits but were among the best entries for resistant to pepper spot and web blotch. Entries 426, 184, and 562 were upright and susceptible to pepper spot, but had resistance to web blotch and the best resistance to Sclerotinia blight. These entries appear to be useful sources of resistance to Sclerotinia blight for breeding programs and for increasing the probability of finding additional sources of resistance in clusters of germplasm identified within the entire USDA collection.

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Manninen, O. M., M. Jalli, R. Kalendar, A. Schulman, O. Afanasenko et J. Robinson. « Mapping of major spot-type and net-type net-blotch resistance genes in the Ethiopian barley line CI 9819 ». Genome 49, n^o 12 (décembre 2006) : 1564–71. http://dx.doi.org/10.1139/g06-119.

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Net blotch of barley ( Hordeum vulgare L.), caused by the fungal phytopathogen Pyrenophora teres Drechs. f. teres Smedeg., constitutes one of the most serious constraints to barley production worldwide. Two forms of the disease, the net form, caused by P. teres f. teres, and the spot form, caused by P. teres f. maculata, are differentiated by the type of symptoms on leaves. Several barley lines with major gene resistance to net blotch have been identified. Earlier, one of these was mapped in the Rolfi × CI 9819 cross to barley chromosome 6H, using a mixture of 4 Finnish isolates of P. teres f. teres. In this study, we used the same barley progeny to map resistance to 4 spot-type isolates and 4 net-type isolates of P. teres. With all net-type isolates, a major resistance gene was located on chromosome 6H, in the same position as described previously, explaining up to 88% of the phenotypic variation in infection response in the progeny. We designate this gene Rpt5. Several minor resistance genes were located on chromosomes 1H, 2H, 3H, 5H, and 7H. These minor genes were not genuinely isolate-specific, but their effect varied among isolates and experiments. When the spot-type isolates were used for infection, a major isolate-specific resistance gene was located on chromosome 5H, close to microsatellite marker HVLEU, explaining up to 84% of the phenotypic variation in infection response in the progeny. We designate this gene Rpt6. No minor gene effects were detected in spot-type isolates. The Ethiopian 2-rowed barley line CI 9819 thus carries at least 2 independent major genes for net-blotch resistance: Rpt5, active against net-type isolates; and Rpt6, active against specific spot-type isolates.

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PINHEIRO, HUDSON TERCIO, JOÃO LUIZ GASPARINI et IVAN SAZIMA. « Sparisoma rocha, a new species of parrotfish (Actinopterygii : Labridae) from Trindade Island, South-western Atlantic ». Zootaxa 2493, n^o 1 (3 juin 2010) : 59. http://dx.doi.org/10.11646/zootaxa.2493.1.5.

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A new species of parrotfish, Sparisoma rocha sp. n., is described from Trindade Island off South-eastern Brazil. It differs from its Western Atlantic congeners by the unique colour pattern of live and freshly preserved individuals: initial phase red overall with a brownish shade from lower jaw to over the abdominal cavity, sparse orange blotches on head, and pale circumpeduncular band; terminal phase reddish brown with orange stripe from jaw angle to end of preopercle, sparse orange blotches on head, three pinkish to reddish stripes from about midline to dorsum, from midline to belly pale greyish green to whitish with suffusion of pale reddish brown, a black spot on base of pectoral fins and a bright-yellow blotch below this spot. Additionally, mitochondrial 12S and 16S rRNA loci sequences do not match any known Sparisoma species. The new parrotfish increases to six the species of the genus Sparisoma recorded from South-western Atlantic.

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Acharya, Sanskriti. « DUAL CULTURE APPROACH FOR THE EVALUATION OF ANTAGONISTIC ACTIVITY OF NATIVE TRICHODERMA ISOLATES AGAINST BIPOLARIS SOROKINIANA ». International Journal of Advanced Research 9, n^o 12 (31 décembre 2021) : 1002–8. http://dx.doi.org/10.21474/ijar01/14000.

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Spot blotch disease caused by Bipolaris sorokiniana (Sacc.) shoem. is one of the most destructive diseases of wheat (Triticum aestivum L.) in plain areas of Nepal. A laboratory experiment was conducted to evaluate the antagonistic activity of seven test Trichoderma isolates obtained from the soil sample by employing dual culture method against spot blotch pathogen of wheat Bipolaris sorokiniana at Plant Pathology Division, Nepal Agriculture Research Council, Khumaltar, Nepal. The experiment was laid out in a Completely Randomized Design (CRD). The result revealed that all Trichoderma isolates showed control over the pathogen. Isolate T517 stands out to be the most effective one giving 67.81% mycelial growth inhibition but isolate T528 was the least effective. Native Trichoderma can have significant biocontrol potential and may provide an effective solution against plant fungal diseases.

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Tyryshkin, L. G., et N. A. Tyryshkina-Shishelova. « Genetics of wheat somaclones resistance to Bipolaris sorokiniana Shoem. » Plant Protection Science 38, SI 1 - 6th Conf EFPP 2002 (1 janvier 2002) : 186–88. http://dx.doi.org/10.17221/10352-pps.

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Genetics of resistance to common root rot and dark brown leaf spot blotch (both caused by Bipolaris sorokiniana Shoem.) was studied in wheat somaclonal lines, obtained in calluses culture of samples 181-5 and Vera. Four different approaches were used: linear analysis of resistance in generations of segregating somaclonal lines, hybridological analysis, study of resistance components, study of possible durability of resistance. Results showed, that resistance to both diseases is likely controlled by polygenic systems with additive actions of minor genes. Different lines possess non-identical genetic systems for resistance. Several lines kept their initial level of resistance to spot blotch after 5 cycles of the pathogen artificial population reproduction.

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Jana, Sakti, et K. L. Bailey. « Responses of Wild and Cultivated Barley from West Asia to Net Blotch and Spot Blotch ». Crop Science 35, n^o 1 (janvier 1995) : 242–46. http://dx.doi.org/10.2135/cropsci1995.0011183x003500010044x.

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Arabi, Mohammad Imad Eddin, et Mohammad Jawhar. « Greenhouse Method for Assessing Spot Blotch Resistance in Barley ». Plant Pathology Journal 26, n^o 4 (1 décembre 2010) : 421–23. http://dx.doi.org/10.5423/ppj.2010.26.4.421.

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Sheridan, J. E., et D. K. Nendick. « Control of spot and net type blotch of barley ». Proceedings of the New Zealand Weed and Pest Control Conference 40 (8 janvier 1987) : 176–78. http://dx.doi.org/10.30843/nzpp.1987.40.9930.

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Siddique, A. B., M. H. Hossain, E. Duveiller et R. C. Sharma. « Progress in Wheat Resistance to Spot Blotch in Bangladesh ». Journal of Phytopathology 154, n^o 1 (janvier 2006) : 16–22. http://dx.doi.org/10.1111/j.1439-0434.2005.01049.x.

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Bovill, Jessica, Anke Lehmensiek, Mark W. Sutherland, Greg J. Platz, Terry Usher, Jerome Franckowiak et Emma Mace. « Mapping spot blotch resistance genes in four barley populations ». Molecular Breeding 26, n^o 4 (16 février 2010) : 653–66. http://dx.doi.org/10.1007/s11032-010-9401-9.

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Roy, Joy K., Kevin P. Smith, Gary J. Muehlbauer, Shiaoman Chao, Timothy J. Close et Brian J. Steffenson. « Association mapping of spot blotch resistance in wild barley ». Molecular Breeding 26, n^o 2 (10 mars 2010) : 243–56. http://dx.doi.org/10.1007/s11032-010-9402-8.

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Arabi, M. I. E. « Inheritance of partial resistance to spot blotch in barley ». Plant Breeding 124, n^o 6 (décembre 2005) : 605–7. http://dx.doi.org/10.1111/j.1439-0523.2005.01156.x.

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Viani, Ali, Parimal Sinha, Taru Sharma et Lal Mohan Bhar. « A model for forecasting spot blotch disease in wheat ». Australasian Plant Pathology 46, n^o 6 (6 septembre 2017) : 601–9. http://dx.doi.org/10.1007/s13313-017-0514-z.

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McLean, Mark S., Barbara J. Howlett et Grant J. Hollaway. « Epidemiology and control of spot form of net blotch (Pyrenophora teres f. maculata) of barley : a review ». Crop and Pasture Science 60, n^o 4 (2009) : 303. http://dx.doi.org/10.1071/cp08173.

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Spot form of net blotch (SFNB), caused by the fungus Pyrenophora teres f. maculata, was first described in Denmark in the 1960s and is now a prevalent foliar disease of barley in many countries. This disease should be controlled as a separate disease-causing organism from the net form of net blotch (NFNB), which is caused by P. teres f. teres. The increase in prevalence of SFNB is primarily due to stubble retention and cultivation of susceptible varieties, which have resulted in increased inoculum. Infected barley stubble is the primary inoculum source for SFNB, producing both asexual spores (conidia) and sexual spores (ascospores) from pseudothecia. Spot form of net blotch causes significant losses in grain yield and quality in situations where inoculum is present, susceptible varieties are cultivated, and where the climate is cool and moist. Cultivation of resistant varieties is the most cost-effective method for control of SFNB and more than 12 different resistance sources have been identified in barley germplasm and wild barley relatives. The resistance loci of 11 of these have been mapped. Control of SFNB can also be achieved with application of foliar fungicides, crop rotation, and stubble destruction.

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McLean, Mark S., Barbara J. Howlett et Grant J. Hollaway. « Erratum to : Epidemiology and control of spot form of net blotch (Pyrenophora teres f. maculata) of barley : a review ». Crop and Pasture Science 60, n^o 5 (2009) : 499. http://dx.doi.org/10.1071/cp08173_er.

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Spot form of net blotch (SFNB), caused by the fungus Pyrenophora teres f. maculata, was first described in Denmark in the 1960s and is now a prevalent foliar disease of barley in many countries. This disease should be controlled as a separate disease-causing organism from the net form of net blotch (NFNB), which is caused by P. teres f. teres. The increase in prevalence of SFNB is primarily due to stubble retention and cultivation of susceptible varieties, which have resulted in increased inoculum. Infected barley stubble is the primary inoculum source for SFNB, producing both asexual spores (conidia) and sexual spores (ascospores) from pseudothecia. Spot form of net blotch causes significant losses in grain yield and quality in situations where inoculum is present, susceptible varieties are cultivated, and where the climate is cool and moist. Cultivation of resistant varieties is the most cost-effective method for control of SFNB and more than 12 different resistance sources have been identified in barley germplasm and wild barley relatives. The resistance loci of 11 of these have been mapped. Control of SFNB can also be achieved with application of foliar fungicides, crop rotation, and stubble destruction.

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