杂交竹基腐病生防真菌及其水分散粒剂研制与防效

Biocontrol Fungus against Base Rot of Bambusa pervariabilis×Dendrocalamopsis grandis and Its Preparation and Effect of Water-Dispersing Granule

为研制出可用于防治杂交竹基腐病的高效制剂,采用稀释平板法从健康杂交竹根际土中分离真菌;经平板对峙法筛选出对病原菌抑制作用较好的菌株RS05,通过形态学和分子生物学鉴定为螺旋木霉。在基础培养基和发酵条件优化的基础上,筛选出水分散粒剂最适载体与助剂。结果表明,RS05最适培养基为PSA;发酵条件为接种量8%、pH=6、发酵6 d、180 r/min、在26℃~27℃下光培养。水分散粒剂最佳配方为:润湿剂3%吐温20、紫外保护剂0.3%糊精、黏结剂3%可溶性淀粉、崩解剂5%氯化钠、稳定剂0.3%碳酸钙、孢子悬浮液20%、载体硅胶补足100%。盆栽试验结果显示,RS05水分散粒剂在稀释200倍以下时防效均高于88%,略高于市售化学制剂86%,显著高于市售生防制剂64%。综上所述,螺旋木霉RS05水分散粒剂对撑×绿杂交竹基腐病防治效果优良。

To develop an effective preparation for controlling the base rot disease of Bambusa pervariabilis×Dendrocalamopsis grandis,the fungi were isolated from the rhizosphere soil of healthy bamboo by the dilution plate method.The strain RS05 was screened by the plate confrontation method and identified as Trichoderma spiralis by the morphological and molecular biological analyses.Based on the optimization of basic medium and fermentation conditions,the optimum carrier and additive of water-dispersible granule were screened.The results showed that the optimum medium for RS05 was PSA.The fermentation conditions were as follows:inoculation amount 8%,pH 6,fermentation time 6 d,180 r/min,light culture at 26℃~27℃.The best prescription of water-dispersible granules were comprised 3%Tween 20(wetting agent),0.3%dextrin(UV protection agent),3%soluble starch(binding agent),5%sodium chloride(disintegrating agent),0.3%calcium carbonate(stabilizer),20%spore suspension,and silica gel(carrier)complemented 100%.The results of pot experiments indicated that the control effect of RS05 water-dispersible granules was higher than 88%when diluted less than 200 times,slightly higher than 86%of commercially available chemical preparations,and significantly higher than 64%of commercially available biocontrol preparations.In conclusion,the water-dispersible granules of T.spiralis RS05 has excellent control effect on the base rot disease of B.pervariabilis×D.grandis.