蔗根土天牛高致病力绿僵菌菌株的生物学特性研究

Biological characteristics of a strain of Metarhizium that is highly pathogenic to Dorysthenes granulosus

【目的】明确对蔗根土天牛Dorysthenes granulosus具有良好杀虫活性的金龟子绿僵菌Metarhizium anisopliae JC002菌株生长和产孢所需要的最适营养条件和环境条件。【方法】通过单因素试验,测试了不同培养基、碳源、氮源、温度、pH及紫外线照射不同时间对JC002菌株生长和产孢的影响。【结果】JC002菌株培养基的最佳配方是葡萄糖30 g、蛋白胨15 g、马铃薯200 g、琼脂20 g、水1 000 mL;蔗糖、NaNO3是菌落生长及产孢的最适碳源和氮源;菌株培养的最适温度为25℃,培养基的最适pH值为7.0;紫外光对菌株的生长速率无显著影响,但对产孢量有较大的抑制作用,紫外光照射时间越长,产孢越少。【结论】本研究为JC002菌株的大量培养及其孢子制剂的大量生产和有效利用奠定基础。

[Objectives] The purpose of this paper was to explore the nutritional and environmental conditions for required for the hyphal growth and sporulation of Metarhizium anisopliae JC002, a newly isolated fungal strain with high insecticidal activity to the larvae of Dorysthenes granulosus. [Methods] Effects of different factors, such as culture medium, carbon sources, nitrogen sources, temperature, pH and UV on hyphal growth and sporulation were tested by single factor tests. [Results] The results indicate that the optimum formula for growing the JC002 strain was 30 g glucose, 15 g peptone, 200 g potatoes, 20 g agar and 1 000 mL water. Sucrose and NaNO3 were the best carbon and nitrogen source. The most suitable culture temperature was 25℃ and the optimum pH-value was 7.0. UV had no significant impact on the growth rate of the fungus but seriously inhibited its sporulation. [Conclusion] This study provides scientific basis for both the large-scale culture of the JC002 strain, and also the mass production and effective utilization of conidia of this strain.