Barley foliage diseases, field pea diseases.

85BA22, 85MT31, 85N053, 85BA24, 85MT32, 85MT32, 85N052, 85N053, 85BA21, 85MT30, 85BA21, 85BA22, 85MT31, 85MT43, 85KA59, 85KA60, 85M29, 85MT44, 85E22, 85ES22, 85ES23, 85N051, 85BA25, 85WH27, 85C65, 85C69, 85C66, 85C67, 8SKA48, 8SMT34, 85KA47, 85MT33, 85M26, 85ME26, 85KA49, 85KA51. A.General Notes and Highlights BARLEY FOLIAGE DISEASES B. Scald: Screening fungicides c. Scald: Fungicidal control in Northam district D. Scald: Effect of seeding rate E. Scald & Mildew Effect of fungicides and rates F. Scald & Mildew Seed borne infection and seed dressing G. Scald & Mildew Effect of seed dressing and spraying H. Scald & Mildew Effect of Erex and Baytan I. Mildew: Cultivar x seed dressing J. Mildew: Comparing fungicides K. Mildew: Simulated Stubble mulching L. Mildew: Cultivar mixtures M. Net-Blotch: Seed borne infection and its control N. Net-Blotch: Screening fungicides O. Spot-type Net-Blotch Potential yield losses P. Spot-type Net-Blotch Effect of date of sowing Q. Spot-type Net-Blotch Simulated stubble mulching FIELD PEA DISEASES R. Black spot: Potential crop losses S. Black spot: Seed dressings T. Black spot: Monitoring Air borne infection U. Black spot: Screening for resistanc

Evaluation of Barley Genotypes Against Spot Blotch Disease in Inner Tarai Region of Nepal

Spot blotch caused by Bipolaris sorokiniana (Sacc. in Sorok.) Shoem. is an important disease of barley (Hordeum vulgare L.). A total of 126 barley genotypes received from Hill Crops Research Program, Kabre, Dolakha having SoluUwa as a susceptible check and Bonus as a resistant check were evaluated as barley disease screening nursery (BDSN) under natural epiphytotic condition at National Maize Research Program, Rampur, Chitwan during winter seasons of 2017 and 2018. The nursery was planted in augmented design. The resistant and susceptible checks were repeated and planted after each 10 tested entries. The unit plot size was 2 rows of one meter length for each genotype planted continuously with 25cm row to row spacing. The seed rate was 100 kg/ha. The recommended fertilizer dose of 23:30:0 N:P2O5:K2O kg/ha was applied. The double digit scale (00 to 99) was used to measure overall foliar infection on the whole plant during flowering, soft dough and hard dough stages. Other agronomic practices were followed as per recommendation. Genotypes B86019-1K-3K-0K3, ACC 2087, ACC 2441, ACC GHv-06816, ACC 1597, ACC 1612, ACC 2059 and ACC 2032 were resistant against spot blotch disease. Similarly, 32 barley genotypes were moderately resistant and rest of the tested genotypes were susceptible to the disease. The selected resistant barley genotypes can be used in crossing program and/or promoted for further testing to develop spot blotch resistant varieties for inner Tarai region of Nepal

Kasvitautien esiintyminen viljalajikkeilla virallisissa lajikekokeissa 2008–2015

Virallisten lajikekokeiden tarkoituksena on kasvilajikkeiden viljelyarvon arviointi. Viljalajikkeiden taudinkestävyys on tärkeä osa viljelyarvoa ja lajikkeiden taudinkestävyys on merkittävä osa integroitua kasvinsuojelua. Tiedot kasvitautien esiintymisestä eri lajikkeilla perustuvat lumihomeen, härmän, ruosteiden ja pääosin myös lehtilaikkutautien osalta virallisten lajikekokeiden kenttäkokeista vuosina 2008–2015 tehtyihin kasvitautihavaintoihin. Kasvitautien esiintyminen kokeissa perustui luonnolliseen tartuntaan. Lajikkeiden vehnän rusko- ja pistelaikun sekä ohran tyvi- ja lehtilaikun ja verkkolaikun laikkutyypin kestävyyttä tutkittiin infektiokokeilla. Pistelaikkutulokset ovat vuosilta 2008–2015, ruskolaikkutulokset 2008–2013 sekä 2015 ja ohran tyvi- ja lehtilaikku- sekä verkkolaikun laikkutyyppitulokset vuosilta 2011–2015. Tautitulokset analysoitiin käyttäen lineaarisia sekamalleja. Tuloksena saadut lajikekohtaiset tautikeskiarvot ovat keskenään vertailukelpoisia lajikkeiden koejaksojen erilaisuudesta huolimatta. Kontrollilajikkeet on sijoitettu testattavien lajikkeiden joukkoon tautimäärän mukaiselle sijalle.The purpose of the official variety trials is to evaluate the cultivation value of plant varieties. Plant disease resistance is an important factor in the cultivation value of cereal varieties and has an essential role in integrated pest management. Most of the information on the incidence of diseases on cereal varieties, snow mould, powdery mildew, rusts and leaf spot diseases, in this report is based on the observations made on the official variety field trials during 2008–2015. Disease pressure in the trials was based on natural infection. The susceptibility of spring wheat varieties to Stagonospora blotch and tan spot and barley varieties to spot blotch and spot type net blotch were tested in separate infection trials. The trials of tan spot were done in 2008–2015, the trials of Stagonospora blotch in 2008–2013 and 2015 and the trials of spot blotch and spot type net blotch in 2011–2015. The data was analyzed using linear mixed models. The estimated means of the varieties are comparable despite the different trial periods. The results of the controls and all the other varieties are given in the tables in order of susceptibility.20152. korjattu paino

Summary of experiments.

(I) General comments and highlights. (II) Scald: Fungicidal control. 82BA21, 82E18, 82MT19, 82WH23, 82WH23. (III) Scald: Opportunity trial on fungicidal control. 82AL85, 82BA22, 82MT20. (IV) Scald: Epidemic in segregating populations. (V) Scald: Host reaction in hill plots and single plants. 82MT21, 82BA23, (VI) Scald: Seeding rate in evaluating cultivars for resistance. 82MT22, (VII) Net-type net blotch: Screening fungicides. 82BA25, 82KA25. (VIII) Net-type net blotch: Reactions in single plants and hill plots. 82A3, 82BA26. (IX) Spot-type net blotch: Screening fungicides. 82C16. (X) Spot-type net blotch: Potential yield losses. 82C14, 82C15. (XI) Effect of simulated stubble mulching on disease and yield. 82BA36, 82BA35, 82C32, 82MT43,82N27. (XII) Maximising barley yield: Fungicide x growth regulator x cultivar. 82E19,. (XIII) Maximising barley yield: Fungicide x cultivar x nitrogen. (XIV) Variation in pathogenicity of scald, net blotch and powdery mildew. (XV) Unidentified leaf spot on forrest barley. (XVI) Opportunity trial on powdery mildew

High damage potential of seed-borne spot blotch in organically grown spring barley in Denmark

Spot blotch of barley (Bipolaris sorokiniana, perfect state: Cochliobolus sativus) occurs wherever barley is grown but is normally not considered a major problem in Danish barley production. It is therefore not included in routine disease surveys or official variety testing in Denmark. However, recommended seed contamination thresholds are 30% for spring barley and 15% for winter barley. Several spring barley varieties were grown under organic (no seed dressing, mechanical weeding) and conventional (seed dressing with fungicides, herbicide application) production conditions at three sites in Denmark in 2003. The harvested seeds were analysed for contamination levels of seed-borne B. sorokiniana using a blotter method. The percentage of seeds contaminated with B. sorokiniana ranged from about 5 to 95 % and was highly depending on the site, production system and variety. Contamination levels of organically cultivated plots were about twice as high as those of plots receiving conventional treatments. The germinating ability of seeds was highly affected by the level of B. sorokiniana contamination and declined drastically at contamination levels above 60%. This effect appeared to differ among varieties. The 1000-grain weight was not affected by the level of spot blotch contamination of seeds. The results indicate that the importance of spot blotch may be underrated, especially in organic barley production and that the role of varietal resistance should be investigated. More results are expected from ongoing seed analyses

Barley foliage diseases, Field pea diseases

A. Experimental Notes. Barley foliage diseases: B. Scald: Effect of various fungicides. c. Scald: Response of cultivars to fungicides. D. Scald: Effect of seeding rate on infection and yield. E. Scald: Testing of fungicides S3308L. F. Net blotch: Potential yield losses. G. Net blotch: Screening fungicides. H. Spot type net blotch: Simulated stubble retention. I. Spot type net blotch: Potential yield losses. J. Powdery mildew: Effect of simulated stubble retention. K. Powdery mildew: Time of fungicide application. L. Powdery mildew: Comparing fungicides. M. Powdery mildew: Testing fungicide S3308L. N. Powdery mildew: Response to Erex in farmer\u27s crops. o. Disease development and yield in barley cultivars. P. Response to Bayleton in farmer\u27s crops. Q. Disease resistance in stage 4 barley cultivars. Field pea diseases R. Black spot: Seed dressing and spray timing. S. Field Pea disease survey

Identification of pathogens and control of spot blotch disease of barley (Hordeum vulgare) by combining plant resistance and biological control

PhD ThesisSpot blotch is one of the most important diseases of barley (Hordeum vulgare) in Libya and worldwide. The overall aim of this study was to investigate the potential of biological control in combination with disease resistance to control spot blotch without the potential hazards of chemical application. Fungi were isolated from barley plants with spot blotch symptoms from different areas in Libya. As well as the commonly known spot blotch pathogen Bipolaris sorokiniana (teleomorph Cochliobolus sativus), Bipolaris spicifera (teleomorph Cochliobolus spicifer), Curvularia inaequalis, and Alternaria alternata were identified by their morphology and ribosomal DNA sequences. Bipolaris sorokiniana was the most serious pathogen under the test conditions; the others infected barley but caused less severe symptoms. Spot blotch resistance of barley seedlings was tested under greenhouse conditions with four Libyan cultivars (ACSAD, Nibola, Rehan, and Wadi Utbah) and two UK cultivars (Gaelic and Pastoral). Nibola was the most resistant. The ability of the organisms in three commercial biocontrol products, Trichoderma harzianum T-22 (Trianum), Streptomyces lydicus WYEC 108 (Actinovate) and Bacillus subtilis QST 713 (Serenade), to control spot blotch individually and in combination was investigated. On agar plates, all three inhibited growth of the pathogens completely on the second day of culture, except that for B. spicifera with S. lydicus there was an inhibition zone and the pathogen grew in the opposite direction. Disease severity was lowest when T. harzianum T-22 was applied individually to the most resistant cultivar, Nibola. Foliar application, soil treatment and seed coating all reduced disease severity. With foliar application, T. harzianum T-22 was more effective when applied at the same time as the pathogen than when applied one week before or four days after. In a field experiment with T. harzianum T-22, foliar application combined with seed treatment suppressed spot blotch more effectively than either method individually.The Libyan Authorities

Association mapping of spot blotch resistance in wild barley

Spot blotch, caused by Cochliobolus sativus, is an important foliar disease of barley. The disease has been controlled for over 40 years through the deployment of cultivars with durable resistance derived from the line NDB112. Pathotypes of C. sativus with virulence for the NDB112 resistance have been detected in Canada; thus, many commercial cultivars are vulnerable to spot blotch epidemics. To increase the diversity of spot blotch resistance in cultivated barley, we evaluated 318 diverse wild barley accessions comprising the Wild Barley Diversity Collection (WBDC) for reaction to C. sativus at the seedling stage and utilized an association mapping (AM) approach to identify and map resistance loci. A high frequency of resistance was found in the WBDC as 95% (302/318) of the accessions exhibited low infection responses. The WBDC was genotyped with 558 Diversity Array Technology (DArT®) and 2,878 single nucleotide polymorphism (SNP) markers and subjected to structure analysis before running the AM procedure. Thirteen QTL for spot blotch resistance were identified with DArT and SNP markers. These QTL were found on chromosomes 1H, 2H, 3H, 5H, and 7H and explained from 2.3 to 3.9% of the phenotypic variance. Nearly half of the identified QTL mapped to chromosome bins where spot blotch resistance loci were previously reported, offering some validation for the AM approach. The other QTL mapped to unique genomic regions and may represent new spot blotch resistance loci. This study demonstrates that AM is an effective technique for identifying and mapping QTL for disease resistance in a wild crop progenitor

Mapping spot blotch resistance genes in four barley populations

Bipolaris sorokiniana (teleomorph: Cochliobolus sativus) is the fungal pathogen responsible for spot blotch in barley (Hordeum vulgare L.) and occurs worldwide in warmer, humid growing conditions. Current Australian barley varieties are largely susceptible to this disease and attempts are being made to introduce sources of resistance from North America. In this study we have compared chromosomal locations of spot blotch resistance reactions in four North American two-rowed barley lines; the North Dakota lines ND11231-12 and ND11231-11 and the Canadian lines TR251 and WPG8412-9-2-1. Diversity Arrays Technology (DArT)-based PCR, expressed sequence tag (EST) and SSR markers have been mapped across four populations derived from crosses between susceptible parental lines and these four resistant parents to determine the location of resistance loci. Quantitative trait loci (QTL) conferring resistance to spot blotch in adult plants (APR) were detected on chromosomes 3HS and 7HS. In contrast, seedling resistance (SLR) was controlled solely by a locus on chromosome 7HS. The phenotypic variance explained by the APR QTL on 3HS was between 16 and 25% and the phenotypic variance explained by the 7HS APR QTL was between 8 and 42% across the four populations. The SLR QTL on 7HS explained between 52 to 64% of the phenotypic variance. An examination of the pedigrees of these resistance sources supports the common identity of resistance in these lines and indicates that only a limited number of major resistance loci are available in current two-rowed germplasm

Experimental summary 1987

Barley II. Scald and mildrew : Seed dressings and sprayings(87E26, MT37 and MT38) III. Scald and mildew : Seed dressing and fungicide coated superphosphates. (87E27, MT39, MT40 and WH40) IV. Scald and mildew : Fungicides for longer protection (87ES38 and MT41) V. Mildew : Survey of virulence genes (87ES46, MT56 and PE22) VI. Spot-type net blotch : Potential crop losses (87C49 and C55) VII. Spot-type net blotch : Effect of seed dressings (87C49 and C55) VIII. Spot-type net blotch : Parent-offspring regression (87C51 and C56) IX. Leaf stripe : Effect of seed dressings (87M42, MT33 and NA74) Peas X. Blackspot : Effect of fungicides (87MT42 and WH41) XI. Blackspot : Screening for cultivar resistance (87MD10 and MT43