棉铃疫病潜伏侵染的研究  

PRELIMINARY STUDIES ON QUISCENT INFECTION IN COTTON BOLL BLIGHT CAUSED BY PHYTOPHTHORA BOEHMERIAE

作　　者：单卫星[1] 李君彦[1] 

机构地区：[1]西北农业大学植保系,陕西杨陵712100

出　　处：《西北农业学报》1992年第4期87-91,共5页Acta Agriculturae Boreali-occidentalis Sinica

摘　　要：分离试验确证,存在于抗病阶段棉铃上限制性褐色坏死病组织中,疫病菌并不完全失活,说明该病菌存在潜伏侵染。州铃的抗病性表现在抗扩展上。棉铃的抗病性与其发育阶段和环境条件密切相关。花后35天以上的棉铃感病,而花后25天以前的幼铃高度抗病。初步认为,疫病菌侵染后诱导发生的病变特别是酮溶性植物抗毒素的累积,是病菌潜伏侵染及棉铃阶段抗病性的重要机制。高湿等极端环境能诱发抗病阶段的幼铃高度感病。Results from artificially inoculated cotton bolls with zoospores of Phytophthora boehmeriae indicated that quiscent infection may be one of the characteristics of cotton boll blight. The resistance of cotton bolls was closely associated with their development stages. Bolls older than 35 days post-anthesis are susceptible whereas bolls younger than 25 days post-anthesis are resistant to colonization by P. boehmeriae. The pathogen can complete infection within hours when zoospores are used as inoculum, and remain dormant in necrotic spots. Post-infectional changes in particular phytoalexin(s), acetone-soluble chemical (s), accumulation may be one of the factors responsible for the quiscent infection, and also for temporary resistance expressed by cotton bolls at some development stages. Diverse physical conditions such as high humidity in rainy days are responsible for inducing bolls at resistant stages susceptible to colonization by P. boehmeriae.

关 键 词：棉铃疫病菌 潜伏浸染 棉花 

分 类 号：S435.621.2[农业科学—农业昆虫与害虫防治]