宁夏红枣叶斑病病原菌鉴定及室内药剂筛选

Identification of the Pathogenic Fungus Causing Leaf Spot of Zizyphus jujubain Ningxia and Fungicide Screening in Laboratory

以宁夏红枣叶斑病典型病叶为试材,采用组织分离法、离体叶片菌块接种法和菌丝生长抑制法,研究了该地区红枣叶斑病的致病菌种类及有效防治药剂。结果表明:从宁夏红枣叶斑病典型病叶上主要分离得到匍柄霉属真菌(Stemphyliumsp.),占总分离物的85.0%,其中匍柄霉菌株Y-14具有很强的致病性,是宁夏红枣叶斑病的主要病原菌种类;7种杀菌剂对病原菌的毒力强弱依次为25%丙环唑EC>25%咪鲜胺EC>1 000亿/g枯草芽孢杆菌WP>10%多抗霉素WP>250g/L嘧菌酯SC>70%代森锰锌WP>1%申嗪霉素SC,尤其前5种杀菌剂的EC50值<1.0g/L,可作为宁夏红枣叶斑病生物防治和化学防治的首选药剂。

Taking typical leaves of leaf spot of Zizyphus jujubain Ningxia as materials,the main pathogen species of leaf spot of Zizyphus jujubain the region and effective fungicides against the disease were studied by the tissue isolation,detached leaves inoculation and inhibition method of mycelial growth.The results showed that Stemphyliumsp.were isolated from typical leaves of leaf spot of Zizyphus jujubain Ningxia and accounted for 85%of the pathogen total isolates.Among them,strain Y-14 of Stemphyliumsp.had very strong pathogenicity and was confirmed as the main pathogen species of leaf spot of Zizyphus jujubain Ningxia;Virulences of 7kinds of fungicides on pathogen were 25%propiconazole EC〉25%prochloraz EC〉10^10/g Bacillus subtilis WP〉10%polyoxin WP〉250g/L azoxystrobin SC〉70% mancozeb WP1%phenazine-1-carboxylic acid SC,especially EC〉50 value of anterior 5kinds of fungicides were less than 1.0g/L,so they should be the best fungicides of leaf spot of Zizyphus jujubain Ningxia for effective biological and chemical control.