The biocontrol capability of Candida guilliermondii (Cast) Langeroret Guerra against Rhizopus stolonifer (Ehrenb.ex Fr.) Vuill. postharvest rot of peach fruits was studied in vitro and in vivo under different storage temperatures. C. guilliermondii at 5.0×108 CFU (colony-forming unit)/mL of washed cells provided complete control of 5×104 spores /mL of R. stolonifer during storage at 25 ℃ for 4 d, 15 ℃ for 7 d and 3℃ for 30 d. Temperature had no significant effect on the biocontrol efficacy. Antagonist population increased 45.6, 34.4 and 33.1 times per site at 25℃, 15℃ and 3℃ for 3, 3 and 7 d，respectively, then the population stabilized for the remaining storage period. Cell-free culture filtrate of C. guilliermondii was not effective in preventing decay and resulted in even greater lesion diameter than those of sterile distilled water at 3 ℃.These results showed that competition for nutrient, not antibiotic production, plays a major role in the biocontrol capability of C. guilliermondii against rhizopus rot of peach fruits. As the interval between wounding and inoculation with the pathogen increased from 0 to 72 h, susceptibility of wounds to decay by R. stolonifer decreased from 100% of 0 h to 5% of 4 h and 0% of 24 h, then increased to 10% of 48 h and 40% of 72 h.
枯草芽孢杆菌B-912）对桃和油桃褐腐病的抑制效果
范青 田世平* 李永兴 徐勇 汪沂
（中国科学院植物研究所，北京100093）
摘要：研究了不同处理的枯草芽孢杆菌 (Bacillussubtilis (B-912 ) )在不同贮藏温度下对采后桃 (Prunuspersica L .)和油桃 (P .persicavar.nectarina Maxim .)褐腐病 (Moniliniafructicola (G .Wint)Honey)的防治效果。 2 5℃和 15℃贮藏温度下油桃的发病率一般高于桃 ,但在冷藏期间其发病率却一般低于桃。 10 6CFU/mL(CFU :Colony-FormingUnits,菌落形成单位 )的B-912能显著地降低褐腐病的发生 ,桃和油桃的发病率仅分别为 2 0 %和 40 %。 10 8CFU /mL的B-912能完全抑制贮藏在 2 5℃和 3℃下油桃和桃果实褐腐病的发生。单独接种 2 %CaCl2 的果实发病率显著地低于不加Ca2 + 的果实 ,但Ca2 + 和B-912配合运用时对褐腐病的抑制效果并不明显。B-912与扑海因配合使用能显著地抑制褐腐病的发生 ,其抑病效果好于单独使用B-912或扑海因的效果。B-912的滤液在invitro上能有效地抑制病菌孢子的萌发 ,在invivo上也能明显地抑制桃和油桃褐腐病的发生。由此表明 :B-912的抑菌机理与其产生的抗菌物质有关。
关键词： 枯草芽孢杆菌；桃；油桃；褐腐病；生物防治
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