Plant Pathology Division, Department of Plant, Soil, and Entomological Sciences, and Department of Bacteriology and Biochemistry, University of Idaho, Moscow, Idaho 83843.
Appl Environ Microbiol. 1991 Oct;57(10):2864-7. doi: 10.1128/aem.57.10.2864-2867.1991.
The biocontrol fungi Trichoderma harzianum, used to control soilborne plant pathogens, and Beauveria bassiana, used to control insect pests, were formulated as mycelial biomass in alginate pellets with wheat bran added. After drying for 0, 4, or 16 h, pellets were placed in water or in aqueous solutions of polyethylene glycol (PEG) 8000 for 4 to 24 h and then allowed to continue drying. PEG-treated pellets containing T. harzianum showed significantly greater proliferation of hyphae in soil than untreated pellets or pellets treated with water. Production of conidia of T. harzianum from PEG-treated pellets was lower than production from untreated pellets after 4 days, although rates were equivalent after 7 days. In contrast, production of conidia of B. bassiana was significantly more rapid from PEG-treated pellets than from untreated pellets. Biocontrol of soilborne plant pathogens or insect pests may be enhanced by rapid hyphal growth of T. harzianum in soil or rapid sporulation of B. bassiana on foliage, respectively. Therefore, PEG treatment may improve the efficacy of these biocontrol agents.
生防真菌哈茨木霉，用于防治土传植物病原菌，球孢白僵菌，用于防治昆虫害虫，被制成含有麦麸的海藻酸钠颗粒中的菌丝体生物量。在干燥 0、4 或 16 h 后，将颗粒放入水或聚乙二醇（PEG）8000 的水溶液中 4 至 24 h，然后继续干燥。与未处理的颗粒或用水处理的颗粒相比，含有哈茨木霉的 PEG 处理的颗粒在土壤中的菌丝增殖显著增加。从 PEG 处理的颗粒中产生的哈茨木霉分生孢子的产量在第 4 天低于未处理的颗粒，尽管在第 7 天，两者的速率相当。相比之下，从 PEG 处理的颗粒中产生的球孢白僵菌分生孢子的速度明显快于未处理的颗粒。哈茨木霉在土壤中的菌丝快速生长或球孢白僵菌在叶片上的快速产孢可能分别增强对土传植物病原菌或昆虫害虫的生物防治。因此，PEG 处理可能会提高这些生防剂的功效。
