稻纹枯病人工发病简易方法的实用性分析

Analysis on practicability of inducing artificially rice disease caused by Rhizoctonia solani

采用水稻纹枯病病原菌菌丝块为接种体,在水稻不同生育期进行离体和活体接种,测定了3个菌株(2008-20-1、2008-22-2、2008-27-2)人工接种方法的有效性及其致病力差异。结果表明,3个菌株在针叶期、6叶期、成株期叶片,6叶期和成株期茎秆上活体接种与在6叶期和成株期的离体叶片接种,均导致正常发病,产生典型的云纹状坏死病斑。除了在6叶期和成株期活体茎秆上接种的不能区分菌株2008-27-2和2008-20-1间的致病力差异之外,其他活体接种和离体接种方法都可有效区分所用的3个菌株间的致病力差异。分析比较了试验过程占用的空间和时间条件,以及发病条件局部控制的难易性。

Effectiveness of artificial inoculation methods using mycelial disc of 3 isolates of fungus Rhizoctonia solani Ktihn, the causal agent of rice sheath blight, at different growth stages of rice with intact plant or detached plant parts was determined. The results showed that normal disease reaction of rice sheath blight with typical necrotic and cloud-like lesion showed in all eases of inoculation on intact leaf of needle stage, 6-1eaves stage, adult stage, on intact stems of 6- leaves stage, adult stage, on detached-leaf blade of 6-1eaves stage and adult stage by 3 isolates. Pathogenicity of the 3 isolates was differentiated effectively by all methods using both intact plant and detached plant parts except for methods using intact stems of 6-1eaves stage and adult stage, in which pathogenicity between isolate 2008-27-2 and 2008-20-1 could not be differentiated. The conditions about space and time taken by trial during implementation process were analyzed and complexity for control of local condition for disease was compared.