Blackleg (Leptosphaeria maculans) Severity and Yield Loss in Canola in Alberta, Canada
نویسندگان
چکیده
Blackleg, caused by Leptosphaeria maculans, is an important disease of oilseed rape (Brassica napus L.) in Canada and throughout the world. Severe epidemics of blackleg can result in significant yield losses. Understanding disease-yield relationships is a prerequisite for measuring the agronomic efficacy and economic benefits of control methods. Field experiments were conducted in 2013, 2014, and 2015 to determine the relationship between blackleg disease severity and yield in a susceptible cultivar and in moderately resistant to resistant canola hybrids. Disease severity was lower, and seed yield was 120%-128% greater, in the moderately resistant to resistant hybrids compared with the susceptible cultivar. Regression analysis showed that pod number and seed yield declined linearly as blackleg severity increased. Seed yield per plant decreased by 1.8 g for each unit increase in disease severity, corresponding to a decline in yield of 17.2% for each unit increase in disease severity. Pyraclostrobin fungicide reduced disease severity in all site-years and increased yield. These results show that the reduction of blackleg in canola crops substantially improves yields.
منابع مشابه
Detection of Leptosphaeria maculans and Leptosphaeria biglobosa Causing Blackleg Disease in Canola from Canadian Canola Seed Lots and Dockage.
Blackleg, caused by Leptosphaeria maculans, is a major threat to canola production in Canada. With the exception of China, L. maculans is present in areas around the world where cruciferous crops are grown. The pathogen can cause trade barriers in international canola seed export due to its potential risk as a seed contaminant. The most recent example is China restricting canola seeds imported ...
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Blackleg, caused by Leptosphaeria maculans, is an economically important disease of canola (Brassica napus). Little is known about the current distribution of pathogenicity groups (PGs) of L. maculans in Canada and the United States. Four hundred and eighty-nine isolates of L. maculans or Leptosphaeria biglobosa from western Canada and North Dakota, United States, were placed in five PGs (PG-1 ...
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