寡聚糖诱抗剂诱导黄瓜抗白粉病的研究

Effect of oligosaccharide on the resistance induction of cucumber against Sphaerotheca fuliginea

以寡聚糖为诱抗剂，研究了其对黄瓜抗白粉病抗病性的诱导作用。结果显示，用寡聚糖诱抗剂在接种前处理黄瓜叶片，可以减轻黄瓜白粉病的发生，表现为菌落稀疏、变小，产孢期延迟、以及潜育期延K。寡聚糖诱抗剂最佳处理时间为接种前5～7d，持效期在10d以上。诱抗剂处理第一片真叶后可减轻上部叶片发病，上部叶片呈现较明显的抗病性反应特征。表明寡聚糖可诱导黄瓜幼苗产生对白粉病的系统获得抗病性。

The expression of systemic acquired resistance （SAR） to Sphaerotheca fuliginea in cucumber, Cucumis sativus L. , treated with oligosaccharide was studied. The results showed that the disease severity of Sphaerotheca fuliginea was reduced on cucumber leaves treated with oligosaccharide before inoculation ,expressing as clone sparsing and decreesing ,sporulation delaying,and incubation prolonging. The proper treat time with oligosaccharide for inducting SAR was 5- 7 days before inoculation with Sphaerotheca fuliginea,The persistence of induced resistance could last 10 d or more. Treating the first true leaf with oligosaccharide could reduce the disease severity on upper leaves,which showed remarkable resistance. This indicates that oligosaccharide could induce the cucumber seedling to express the SAR to Sphaerotheca fuliginea.