6株野生植物内生放线菌防病促生作用的初步研究

为了寻找具有内生习性的植病生防放线菌,从采自秦岭的14种野生植物中分离得到29株内生放线菌,对其进行了皿内拮抗试验、发酵液抑菌试验和温室防病促生试验。结果发现,有6株菌表现出显著的抑菌活性,其中菌株SF1对粉红聚端孢、SF4对苹果炭疽菌、SF20对灰葡萄孢均有较强的抑制作用;菌株SG2的代谢产物具有很高的抑菌活性,其发酵滤液对茄链格孢的抑菌圈直径达到35 mm;菌株SG2对温室番茄早疫病的防治效果达到89.72%,菌株SF4对黄瓜白粉病的温室防效达到89.61%,菌株SF20对番茄和黄瓜具有明显的促生作用。可见,从野生植物中分离具有内生习性和抑菌作用的放线菌,直接用于生物防治是可行的。

Inhibiting and promoting effect on plants of six strains endophytic actinomycetes isolated from wild plants

In order to find new endophytic actinomycetes for biological control,twenty-nine strains of endophytic actinimycetes were isolated from surface-sterilized plant tissues harvested from QinLing. The isolates had been assayed for antagonistic activity, fermentation activity in vitro and greenhouse experiment. The results indicated that SF1 strain had significant inhibiting effect on Trichothecium roseum,SF4 on Colletotrichurn gloeosporioides and strain SF20 on Botrytis cinerea. The fermentation filtrate of SG2 metabolites was detected to have stronger antagonism against Alternaria solani, and inhibiting zone got 35 mm. In greenhouse experimemt, 89.72 % control ratio to A. solani, and 89.61% to Sphaerotheca fuliginea were found by strain SG2 and SF4,respectively,and strain SF20 could promote the growth of tomato and cucumber. The conclusion was drawn that it was feasible for isolated endophytic actinimycetes from wild plants to be applied in biological control.