海水酵母菌的分离鉴定及其在果实贮藏保鲜中的应用

Separation of Bio-antagonists from Sea and the Application in Fruit Postharvest Fresh-keeping

摘要:

本文研究了海水酵母菌对果实腐烂病的防治效果以及其在梨和苹果果实采后贮藏保鲜中的作用。通过显微观察结合分子生物学方法对分离的菌株进行鉴定，结果表明该菌与酵母菌(Galactomyces geotrichum)同源性相近，属于酵母菌类。通过平板抑菌试验及活体试验研究该菌对腐烂病菌的拮抗作用，发现该菌对腐烂病菌具有明显的拮抗作用，活体试验结果表明，5×107 CFU/mL该菌对接种了5×104 spores/mL病原菌的梨和苹果果实腐烂病具有良好的防治效果。经该菌悬浮液浸泡处理的采收后的梨果实，贮藏20 d时的腐烂率比对照少20%，贮藏60 d苹果的腐烂率比对照减少了30%。另外，该菌处理能够延缓梨和苹果果实的软化速率，保持果实较高的营养品质。本研究表明，从海水中分离的酵母菌在果实腐烂病的生物防治和果实保鲜方面具有极大的应用潜力。

Abstract:

The effects of bio-antagonists on the prevention of Valsa ceratosperma and the application in fruit postharvest fresh-keeping of apple and pear were analyzed in this paper. The fungus was classified into Galactomyces geotrichum by microexamination combined with molecular biology. The antagonistic effect of fungus on the fruit Valsa ceratosperma was studied based on the plate bacteriostasis and in vivo experiments, which indicated that the fungus could inhibit Valsa ceratosperma and 5×107 CFU/mL of the fungus had good effect on the prevention of pear and apple rot inoculated with 5×104 spores/ml pathogenic bacteria. Compared with the control fruit, the rot rate of pear treated by the fungi solution decreased 20% after storage 20 d and the apple decreased 30% after storage 60 d. Furthermore, the softening of fruit could be delayed and the fruit maintained good nutritional quality after treated by the fungus. The experiments showed that the fungus separated from sea had high potential in biological control of fruit disease and could be applied in the fruit preservative and fresh-keeping.