du Toit Lindsey J, Derie Mike L, Pelter Gary Q
Washington State University, Mount Vernon REU, Mount Vernon 98273.
Washington State University, Grant/Adams Counties, Ephrata 98823.
Plant Dis. 2004 Oct;88(10):1061-1068. doi: 10.1094/PDIS.2004.88.10.1061.
Of 12 onion seed lots harvested in the semi-arid Columbia Basin of Washington in 1999 or 2000, 8 were infected and 10 infested with Botrytis aclada at incidences of 1 to 10% and 2 to 26%, respectively. Twenty to forty plants were sampled from each of nine direct-seeded, biennial seed crops in April, June, and July 2001 and assayed for Botrytis spp. Six direct-seeded crops were sampled in October and November 2001 and April, June, and July 2002. One bulb-to-seed crop was sampled in April, June, and July 2002. The incidence of B. aclada increased through each season, reaching 100% in most fields by July. Infections were primarily asymptomatic, with no apparent relationship between plant infection and infection of harvested seed. B, cinerea, B. squamosa, and B. porri were detected in 16, 4, and 4% of the fields, respectively, at lower incidences than B. aclada. Harvested seed from 15 of the fields were infected with B. aclada at <1 to 28%. B, cinerea, B. porri, and B. squamosa were detected in three, three, and none of the harvested lots, respectively.
1999年或2000年在华盛顿州半干旱的哥伦比亚盆地收获的12批洋葱种子中，有8批受到感染，10批受到匐柄霉侵染，感染率分别为1%至10%和2%至26%。2001年4月、6月和7月，从9种直播两年生种子作物中各抽取20至40株植株，检测是否存在葡萄孢属真菌。2001年10月和11月以及2002年4月、6月和7月对6种直播作物进行了采样。2002年4月、6月和7月对一种球茎采种作物进行了采样。匐柄霉的感染率在每个季节都有所上升，到7月时大多数田地的感染率达到100%。感染主要无症状，植株感染与收获种子的感染之间没有明显关系。分别在16%、4%和4%的田地中检测到灰葡萄孢、葱鳞葡萄孢和葱葡萄孢，其发生率低于匐柄霉。从15块田地收获的种子受到匐柄霉感染，感染率低于1%至28%。在收获的批次中，分别在3批、3批和0批中检测到灰葡萄孢、葱葡萄孢和葱鳞葡萄孢。
