Effects of Metabolites of Gymnoascus reessii on Plant Seedlings

[Objective] This paper aimed at studying the effects of the metabolites of G.reessii on the growth of plant seedlings to ensure the effective application of this kind of biocontrol factor with potential.[Method] G.reessii with strong nematicidal efficacies on root-knot nematode was used as test material to determine the effects of metabolites of G.reessii on plant activity,the effects of metabolites of G.reessii with different treatments on the growth of plant seedlings and the effects of metabolites of G.reessii with different concentrations on the growth of plant seedlings.[Results] The effects of the metabolites of G.reessii varied on different plants,the influences of metabolites of G.reessii cultured in different media and extracted using different solvent were different on the growth of plant seedlings,and the effects of metabolites of G.reessii with different concentrations on the growth of various plant seedlings were different.[Conclusion] Further studies on the concentrations and application periods of metabolites of G.reessii used in biological prevention and control of root-knot nematode are required.

Galactomyces reessii转化β-甲基丁酸生产β-羟基-β-甲基丁酸

Galactomycesreessii可将 β-甲基丁酸 ( MBA)转化为 β-羟基 - β-甲基丁酸 ( HMB)。摇瓶实验表明发酵过程中提供生长因子的酵母萃取物浓度以 3 g/L较适宜。高浓度钠、铵离子对菌体生长有抑制作用 ,为保证转化 MBA所需 p H可采用混合碱 ( Na OH、KOH、NH4 OH)来调节 ,以防止单一阳离子浓度过高对菌体生长和产物形成的抑制。MBA对菌体生长有明显的抑制作用 ,1 0 g/L的MBA可使菌体浓度减少 3 0 %。分批补料发酵中 ,连续流加葡萄糖和 MBA,控制发酵液中葡萄糖浓度不超过 3 g/L,MBA浓度不超过 4g/L ,1 0 2 h时 HMB浓度达 2 9.0 g/L ,转化率达 5 7.3 % ,HMB平均生产率达 0 .0 98g/( L· h)。

里西裸囊菌代谢产物对植物幼苗的影响研究

[目的]对里西裸囊菌代谢产物对植物幼苗影响进行研究,使该具有潜力的生防因子得到有效应用。[方法]以对根结线虫具有很强杀虫作用的里西裸囊菌为试验材料,测定代谢产物对植物活性的影响,代谢产物活性的差异和不同浓度代谢产物对植物活性的影响。[结果]里西裸囊菌代谢产物对不同植物的影响不同;不同培养基培养和不同溶剂抽提的里西裸囊菌代谢产物对植物的幼苗影响不同;不同浓度里西裸囊菌代谢产物对不同植物幼苗生长影响不同。[结论]还需进一步深入研究该里西裸囊菌代谢物在防治根结线虫时所需的浓度和使用时期。

里西裸囊菌za-130的杀线活性及其影响因素

本文测定了里西裸囊菌Gymnoascus reessiiza-130菌株发酵滤液对南方根结线虫Meloidogyne incognita2龄幼虫的毒杀活性,研究其对分散卵及卵囊孵化的影响及影响因素。结果表明,za-130菌株发酵滤液处理24h和浓缩5倍滤液处理2h后对南方根结线虫2龄幼虫致死率均达到100%;发酵滤液处理3d和10d对分散卵的孵化抑制率均高于87%,对卵囊的孵化抑制率均高于95%;这些均与1μl/ml 1.8%阿维菌素乳油和33μg/ml 10%福气多颗粒剂效果相当。发酵滤液中杀线活性物质具有一定的抗热性、耐pH（1.0~9.0）、抗紫外（照射低于6h）和日光灯照射的能力。