花生白绢病互作研究进展

花生白绢病是由齐整小核菌Sclerotium rolfsii Sacc.引起的发生在花生茎基部的真菌病害，严重制约花生的品质与产量。本研究利用稀释涂布法从怀牛膝根际土壤中分离纯化了116株放线菌，并从中筛选鉴定了能够防控花生白绢病的菌株。通过平板对峙试验筛选得到两株抑菌活性较好且稳定的菌株Soil-1-5和Soil-3-28，它们对齐整小核菌的抑制率分别为80.43%和92.34%。根据形态学观察、生理生化试验及16S rRNA基因序列分析鉴定，两株菌分别被鉴定为疮痂链霉菌Streptomyces scabiei和藤黄灰链霉菌Streptomyces luteogriseus。采用菌丝生长速率法测定了拮抗菌株无菌发酵滤液对植物病原菌的抑制作用。结果表明，菌株Soil-1-5和Soil-3-28的无菌发酵滤液稀释5倍后对齐整小核菌的抑制率分别为73.67%和57.11%，且对禾谷镰孢菌等6种植物病原菌均有不同程度的抑制作用。此外，两菌株的无菌发酵滤液对齐整小核菌菌核萌发和菌核形成也有较好拮抗作用。盆栽试验结果表明，菌株Soil-1-5和Soil-3-28对花生白绢病的防治效果分别为51.92%和31.74%，其中菌株Soil-3-28对花生生长有促进作用。综上，菌株Soil-1-5和Soil-3-28对花生白绢病有较好的防治效果，具有潜在应用价值。

Interaction of peanut and southern blight: a review

Peanut southern blight is a fungal disease which is caused by the pathgen Sclerotium rolfsii Sacc., and seriously restricts the quality and yield of peanut. In this study, 116 strains of actinomycetes were isolated and purified from rhizosphere soil of Achyranthes bidentata by dilution coating method, and the strains that can control peanut southern blight were screened and identified. Two strains, Soil-1-5 and Soil-3-28, with good and stable antifungal activity, were screened by the plate confrontation test, and their inhibition rates were 80.43% and 92.34%, respectively. Morphological observation, physiological and biochemical tests, and 16S rRNA gene sequence analysis identified strains Soil-1-5 and Soil-3-28 as Streptomyces scabiei and Streptomyces luteogriseus, respectively. The inhibition of aseptic fermentation filtrate of antagonistic strains on plant pathogens was measured by mycelium growth rate method. The results showed that after 5 times dilution of aseptic fermentation filtrate of strains Soil-1-5 and Soil-3-28, the inhibit rates of S. rolfsii were 73.67% and 57.11%, respectively, and the two strains had different degrees of inhibition effects on the six plant pathogens including Fusarium graminearum. In addition, the two strains of aseptic fermentation filtrate also had good antagonistic effects on the sclerotinia germination and sclerotinia formation. The results of pot experiment showed that the control effects of strain Soil-1-5 and Soil-3-28 on peanut southern blight were 51.92% and 31.74%, respectively, and strain Soil-3-28 could promote the growth of peanut. In conclusion, strains Soil-1-5 and Soil-3-28 had better control efficacy on peanut southern blight, and had potential application value.