Evaluation of pyraclostrobin as a component in seed and foliar fungicides for the management of blackleg (Leptosphaeria maculans) of canola (Brassica napus)

2020 ◽  
Vol 100 (5) ◽  
pp. 549-559
Author(s):  
Michelle Fraser ◽  
Stephen E. Strelkov ◽  
George D. Turnbull ◽  
Hafiz U. Ahmed ◽  
Wayne Barton ◽  
...  
Keyword(s):  
Brassica Napus ◽  
Untreated Control ◽  
Seed Treatment ◽  
Fungal Pathogens ◽  
Leptosphaeria Maculans ◽  
Susceptible Cultivar ◽  
Brassica Napus L ◽  
Yield Increase ◽  
Novel Target ◽  
Stem Cankers

Infection by Leptosphaeria maculans (Desm.) Ces. & de Not., the causal agent of blackleg of canola (Brassica napus L.), can result in seedling death, foliar lesions, and the development of stem cankers on adult plants. Strobilurin fungicides such as pyraclostrobin are popular, as they are effective against a broad range of fungal pathogens, have novel target specificity, and translaminar activity within the plant. The seed treatment Prosper FX (carbathiin + trifloxystrobin + metalaxyl) and an experimental formulation BAS 720 F (pyraclostrobin + fluxapyroxad + metalaxyl) were evaluated for their efficacy in managing blackleg when applied alone or in combination with the foliar fungicides Priaxor (pyraclostrobin + fluxapyroxad) or Tilt 250 EC (propiconazole). Experiments were conducted with the blackleg-susceptible cultivar ‘Westar’ and the moderately resistant cultivar ‘Dekalb 73-15 RR’ under greenhouse and field conditions in 2012 and 2013. In one greenhouse trial, all fungicide treatments significantly reduced stem blackleg severity on ‘73-15’ and ‘Westar’ compared with the inoculated–untreated controls. During 3 of 4 site-years, the combination of the experimental seed treatment BAS 720 F and Priaxor significantly reduced stem disease severity relative to the inoculated–untreated control by 60%–77% for ‘73-15’ and by 50%–75% for ‘Westar’. This treatment also resulted in a significant yield increase relative to the inoculated–untreated control in ‘Westar’ in 2 site-years by 24% and 56%. The results of the study suggest a reduction in blackleg symptoms and improved yields when canola is treated with a combination of seed and foliar fungicides, especially when cropping a susceptible cultivar.

scholarly journals Genome Mining and Evaluation of the Biocontrol Potential of Pseudomonas fluorescens BRZ63, a New Endophyte of Oilseed Rape (Brassica napus L.) against Fungal Pathogens

2020 ◽  
Vol 21 (22) ◽  
pp. 8740
Author(s):  
Daria Chlebek ◽  
Artur Pinski ◽  
Joanna Żur ◽  
Justyna Michalska ◽  
Katarzyna Hupert-Kocurek
Keyword(s):  
Brassica Napus ◽  
Plant Growth ◽  
Pseudomonas Fluorescens ◽  
Oilseed Rape ◽  
Plant Growth Promotion ◽  
Fungal Pathogens ◽  
Growth Promotion ◽  
Genome Mining ◽  
Plant Colonization ◽  
Brassica Napus L

Endophytic bacteria hold tremendous potential for use as biocontrol agents. Our study aimed to investigate the biocontrol activity of Pseudomonas fluorescens BRZ63, a new endophyte of oilseed rape (Brassica napus L.) against Rhizoctonia solani W70, Colletotrichum dematium K, Sclerotinia sclerotiorum K2291, and Fusarium avenaceum. In addition, features crucial for biocontrol, plant growth promotion, and colonization were assessed and linked with the genome sequences. The in vitro tests showed that BRZ63 significantly inhibited the mycelium growth of all tested pathogens and stimulated germination and growth of oilseed rape seedlings treated with fungal pathogens. The BRZ63 strain can benefit plants by producing biosurfactants, siderophores, indole-3-acetic acid (IAA), 1-aminocyclopropane-1-carboxylate (ACC) deaminase, and ammonia as well as phosphate solubilization. The abilities of exopolysaccharide production, autoaggregation, and biofilm formation additionally underline its potential to plant colonization and hence biocontrol. The effective colonization properties of the BRZ63 strain were confirmed by microscopy observations of EGFP-expressing cells colonizing the root surface and epidermal cells of Arabidopsis thaliana Col-0. Genome mining identified many genes related to the biocontrol process, such as transporters, siderophores, and other secondary metabolites. All analyses revealed that the BRZ63 strain is an excellent endophytic candidate for biocontrol of various plant pathogens and plant growth promotion.

Development of an agronomically superior blackleg resistant canola cultivar in Brassica napus L. using doubled haploidy

1995 ◽  
Vol 75 (2) ◽  
pp. 437-439 ◽  
Author(s):  
G. R. Stringam ◽  
V. K. Bansal ◽  
M. R. Thiagarajah ◽  
D. F. Degenhardt ◽  
J. P. Tewari
Keyword(s):  
Brassica Napus ◽  
Doubled Haploid ◽  
Leptosphaeria Maculans ◽  
Resistance Breeding ◽  
Breeding Method ◽  
Brassica Napus L ◽  
Breeding Lines ◽  
University Of Alberta ◽  
Blackleg Resistance ◽  
The University

The doubled haploid breeding method and greenhouse screening using cotyledon bio-assay were successfully applied to transfer blackleg resistance from the Australian cultivar Maluka (Brassicas napus), into susceptible advanced B. napus lines from the University of Alberta. This approach for blackleg resistance breeding was effective and efficient as several superior blackleg resistant breeding lines were identified within 4 yr from the initial cross. One of these lines (91–21864NA) was entered in the 1993 trials of the Western Canada Canola/Rapeseed Recommending Committee. Key words: Blackleg resistance, Leptosphaeria maculans, doubled haploid, Brassica napus

THE EFFECT OF NITROGEN, SULPHUR AND BORON ON YIELD AND QUALITY OF RAPESEED (Brassica napus L. and B. campestris L.)

1987 ◽  
Vol 67 (3) ◽  
pp. 545-559 ◽  
Author(s):  
W. F. NUTTALL ◽  
H. UKRAINETZ ◽  
J. W. B. STEWART ◽  
D. T. SPURR
Keyword(s):  
Brassica Napus ◽  
Rapeseed Meal ◽  
Yield Response ◽  
Brassica Napus L ◽  
Yield Increase ◽  
Yield And Quality ◽  
Poor Seed ◽  
Pod Development ◽  
Sulphur Fertilizer

In northeastern Saskatchewan on Gray Luvisolic soils, rapeseed (Brassica napus L. and B. campestris L.) grown on many fields does not set seed, possibly because of deficiencies of S and B. Therefore, experiments were begun in 1979 to determine (1) the effect of N, S and B fertilizers on yield and quality of rapeseed; (2) if cultivars (B. napus and B. campestris L.) responded differently to these nutrients; and (3) nutrient and nutrient interaction effects of five rates of N, S and B in a composite rotatable design on yield and quality of the cultivar Regent (B. napus L.). Rates of up to 200 kg N ha−1, 50 kg S ha−1 and 2.8 kg B ha−1 were applied. The experiments were conducted on 13 sites. Nine were in N.E. Saskatchewan on Sylvania f1, Waitville 1 (Luvisolic) and Melfort sicl (Black Chernozemic) soils. Four were in N.W. Saskatchewan on Loon River 1 and Waitville 1, (Luvisolic) soils. In N.W. Saskatchewan there was a significant yield increase because of N (1.00 t ha−1) and S (1.06 t ha−1). In N.E. Saskatchewan on Sylvania f1, rapeseed yields were increased by 0.38 t ha−1 by a combination of S and B and by 0.78 t ha−1 by N. Sylvania f1 soils were lower in soluble B than other experimental sites. At other sites in N.E. Saskatchewan, N but not S increased rapeseed grain yield significantly. Significant response to a combination of S and B was obtained with the cultivar Regent, and both species of rapeseed responded to S fertilizer. Sulphur fertilizer increased the glucosinolate concentration in rapeseed meal at all sites. Sulphur increased oil concentration of rapeseed on all sites except one where frost damaged the crop and increased protein of grain on sites where there was yield response to S. Nitrogen increased protein of rapeseed grown on all sites whereas N combined with B decreased protein and increased oil percentage on all sites except Sylvania f1. The yield response of the cultivar Regent to B was not significantly related to soluble soil B. The combined yield response to S and B in relation to soluble soil S and B was significant (R2 = 0.60). Yield response of rapeseed to S was significantly related to soluble soil S (R2 = 0.35). In conclusion, S fertilizer solved the problem of poor seed set in rapeseed cultivars, but B also enhanced yield by decreasing the number of sterile florets and improving pod development. Key words: Nitrogen, sulphur, boron, rapeseed, oil, protein, glucosinolates

Association mapping of quantitative resistance for Leptosphaeria maculans in oilseed rape (Brassica napus L.)

2010 ◽  
Vol 27 (3) ◽  
pp. 271-287 ◽  
Author(s):  
C. Jestin ◽  
M. Lodé ◽  
P. Vallée ◽  
C. Domin ◽  
C. Falentin ◽  
...  
Keyword(s):  
Brassica Napus ◽  
Association Mapping ◽  
Oilseed Rape ◽  
Quantitative Resistance ◽  
Leptosphaeria Maculans ◽  
Brassica Napus L

The teleomorph of the weakly aggressive segregate ofLeptosphaeriamaculans

2001 ◽  
Vol 79 (4) ◽  
pp. 412-419 ◽  
Author(s):  
R A Shoemaker ◽  
Hortense Brun
Keyword(s):  
New Species ◽  
Brassica Napus ◽  
Helianthus Annuus ◽  
Leptosphaeria Maculans ◽  
Interspecific Crosses ◽  
Phoma Lingam ◽  
Type Specimens ◽  
Brassica Napus L ◽  
Weakly Virulent ◽  
Leptosphaeria Biglobosa

Leptosphaeria biglobosa n.sp. is described for the weakly virulent (or non-aggressive) pathogen causing blackleg of oilseed rape and canola. The new species differs from the aggressive blackleg organism, Leptosphaeria maculans (Desm.) Ces. & De Not. in having a very prominent beak on the ascomata that is greatly enlarged at the apex. Ascomata of both species were produced on canola stems either by inoculation of compatible strains of the Phoma anamorph or by single ascospore isolates at a distance of 1 cm and letting them grow together. Both species exhibit bipolar heterothallism. Interspecific crosses were negative. In a study of type specimens of Leptosphaeria species with 5-septate ascospores infecting Cruciferae, none were found that matched the features of L. biglobosa. Leptosphaeria napi (Fuckel) Saccardo on Brassica napus L., and Leptosphaeria virginica (Cooke & Ellis) Saccardo on Lepidium virginica L., are synonyms of L. maculans. Leptosphaeria submaculans Holm on Sisymbrium, Berteroa, and Erysimum has distinctively enlarged ascospores. Leptosphaeria alliariae (Desm.) Ces. & De Not. on Alliaria officinalis Andrz., has much smaller ascospores. Leptosphaeria lindquistii Frezzi on Helianthus annuus L. of the Asteraceae has ascospores with only one, two, or rarely, three septa but was considered because it too has a Phoma anamorph.Key words: Phoma lingam, B group, ascomata.

Molecular mapping and validation of Rlm1 gene for resistance to Leptosphaeria maculans in canola (Brassica napus L.)

2012 ◽  
Vol 63 (10) ◽  
pp. 1007 ◽  
Author(s):  
Rosy Raman ◽  
Belinda Taylor ◽  
Kurt Lindbeck ◽  
Neil Coombes ◽  
Denise Barbulescu ◽  
...  
Keyword(s):  
Brassica Napus ◽  
Ssr Markers ◽  
Genomic Sequence ◽  
Molecular Mapping ◽  
Durable Resistance ◽  
Leptosphaeria Maculans ◽  
Doubled Haploid Population ◽  
Brassica Napus L ◽  
Breeding Populations ◽  
Independent Population

European winter canola (Brassica napus L.) cultivars harbour genes for durable resistance to the fungus Leptosphaeria maculans, which causes blackleg disease under Australian environmental conditions. Previous studies have shown that resistance in winter-type cultivars Maxol and Columbus is controlled by two genes, Rlm1 and Rlm3, which have been mapped using randomly amplified polymorphic DNA markers onto chromosome A7. We mapped a doubled-haploid population that consisted of 101 lines from a cross between Maxol*1 and Westar-10 using diversity arrays technology and simple sequence repeat (SSR)-based markers. Two SSR marker loci, Xol12-e03 and Xra2-a05b, flanked the Rlm1 locus at an interval of 6.7 cM, which corresponds to ~3.2 Mb of the Brassica rapa genomic sequence; this region contains several genes encoding putative kinase and leucine-rich repeat-type disease-resistance proteins. SSR markers were further tested for their linkage with the Rlm1 locus in an independent population derived from Columbus*3/Westar-10. Our results showed that SSR markers linked to Rlm1 can be useful for monitoring Rlm1 gene introgression in breeding populations derived from Maxol and Columbus.

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