Abstract

Under cool and wet conditions, high levels of botrytis grey mould (BGM) can occur on lentil in western Canada. Identification of local Botrytis isolates from lentil based on conidial morphology (N = 74) and sequence analysis (N = 5) indicated that B. cinerea was the predominant cause of BGM in this region. Eight field experiments at two sites (Saskatoon, SK and Outlook, SK) over two seasons were conducted to evaluate the optimal timing of the fungicide boscalid for the control of BGM in the lentil cultivar ‘CDC Grandora’. Weather conditions limited disease development in one year, but moderate levels were observed in four experiments in the other year. In all experiments, a single application at mid-flower in early-seeded experiments, and at early flower in late-seeded experiments was as efficacious as a double or triple application of boscalid. There were no differences among double application treatments, and at Outlook they were all as efficacious in lowering BGM as the triple application. Despite some differences in BGM severity among fungicide applications, none of the treatments had an effect on yield or seed infection, and there was no correlation between petal colonization by B. cinerea and BGM disease severity under the study conditions.

摘要

在凉爽和潮湿的条件下，加拿大西部的小扁豆上可能会出现高水平的葡萄孢灰霉病（BGM）。基于分生孢子形态（N = 74）和序列分析（N = 5）鉴定的从扁豆中分离出的葡萄孢属菌株表明灰葡萄芽孢杆菌是该地区BGM的主要原因。在两个季节内，在两个地点（萨斯卡通，SK和Outlook，SK）进行了八个田间试验，以评估杀菌剂Boscalid控制扁豆品种“ CDC Grandora”中BGM的最佳时机。天气条件限制了一年的疾病发展，但另一年的四个实验中却观察到中等水平。在所有实验中，早播实验中花的初次施用和晚播实验中花的初次施用均与两次或三次施用鳞茎鳞茎一样有效。两次施用之间没有差异，在Outlook中，它们在降低BGM方面与三次施用一样有效。尽管杀菌剂施用中BGM的严重程度有所不同，研究条件下的灰质芽孢杆菌和BGM疾病严重程度。