烟草主要病害拮抗菌的筛选鉴定及除草活性分析

Screening and identification of antagonistic Trichoderma sp. herbicidal activity against main tobacco diseases

为筛选出对烟草常见病害及烟田杂草具有良好防效的海洋来源生防菌,对海洋红树林来源木霉进行分离纯化,并采用形态学结合分子生物学方法进行种属鉴定,同时还进行抑菌和除草活性测定。结果表明,分离纯化的25株海洋木霉中有棘孢木霉(Trichoderma asperellum)17株,哈茨木霉(T.harzianum)3株,钩状木霉(T.hamatum)2株,里氏木霉(T.reesei)2株,拟康宁木霉(T.koningiopsis)1株。1株里氏木霉HT6,1株钩状木霉HT8,1株拟康宁木霉HT11和10株棘孢木霉HG2、HG9、HG11、HG14、HG16、9HG、HJ3、5HJ、HJ7和HT2对黑胫病菌有明显的抑制效果,抑制率达到60%以上。4株棘孢木霉HG9、HG11、HG16、HT3和1株拟康宁木霉HT11对烟草赤星病菌的抑制率达到40%以上。2株里氏木霉HT6和HT7对青枯菌有抑菌活性,1株钩状木霉HT10对反枝苋有较好的除草活性。

In order to screen herbicide strains with good control over common tobacco diseases and weeds,marine mangrove-derived Trichoderma sp.was isolated and purified.The isolated Trichoderma sp.strains were identified according to morphological characteristics combined with molecular biology,and their antimicrobial as well as herbicidal activities were analyzed.The results showed that there were 17 Trichoderma asperellum strains,including 3 T.harzianum strains,2 T.hamatum strains,2 T.reesei strains and 1 T.koningiopsis strain.Among the above 25 strains,1 T.reesei strain(HT6),1 T.harzianum strain(HT8),1 T.koningiopsis strain(HT11),and 10 T.asperellum strains(HG2,HG9,HG11,HG14,HG16,9HG,HJ3,5HJ,HJ7,HT2)presented significant inhibitory effects on Phytophthora parasitica var.nicotianae with the inhibition rate of more than 60%;4 T.asperellum strains(HG9,HG11,HG16,HT3)and 1 T.koningiopsis strain(HT11)had inhibition effect against Alternaria alternata(Fries)Keissler with the inhibition rate of more than 40%;2 T.reesei strains(HT6 and HT7)possessed inhibitory activity against Ralstonia solanacearum;and 1 T.harzianum strain(HT10)had herbicidal activity against amaranth(Amaranthus retroflexus L.).