关键词: 放线菌;草莓;自毒物质;微生物降解;化感作用

Abstract:

Four strains of actinomyces were used to investigate their abilities in overcoming continuous cropping obstacles and effects on strawberry growth through liquid culture and greenhouse experiments. It was shown that the degradation rates of para-hydroxybenzoic acid in liquid culture by the 4 strains of actinomyces were 97.6%～98.7% after 7 days. Similarly, the para-hydroxybenzoic acid in the strawberry planting soil could be degraded efficiently by these 4 actimonyces in greenhouse experiment. Comparing to the CK treatment, contents of para-hydroxybenzoic acid decreased significantly in the soil around the root when treated by 251, 252 and 40 actinomyces during the planting season was ending. The total weight of strawberry root and new root increased 28.5%～50.4% and 25.7%～802%, respectively, after 4 actinomyces were used, indicating that they could promote the root growth and plant tiller of strawberry. The actinomyces could also decrease mortality and disease rates with relative effects of 51.9%～56.3%. But no significant effects were found on the total weight of strawberry plant, its leaf areas and PPO activity of leaf blades.

Key words: actinomyces, strawberry, autotoxins, microbial degradation, allelopathy