柑橘青、绿霉病高效拮抗菌34-9的筛选及其特性研究

 从柑橘园根际土壤中分离到1株对柑橘青、绿霉病菌有强烈拮抗作用的酵母菌株（34-9），在活体及离体试验中其抑制病菌的作用均较强，在柑橘果实表面接种6 d未发病。其上清液和灭菌液对柑橘青、绿霉病菌没有抑制作用，初步断定该菌株不产生抗生素。经形态特征和生理生化检测，确定其为柠檬形克勒克酵母菌（Kloeckera apiculata）。扫描电镜观察表明，酵母菌株（34-9）对柑橘青、绿霉病菌直接作用，可观察到酵母菌株（34-9）紧紧包围柑橘青、绿霉病菌菌丝或附着吸附在柑橘青、绿霉病菌菌丝上，最终使柑橘青、绿霉病菌菌丝浓缩，菌丝畸形。

Characteristics and Identification of an Antagonistic Yeast 34-9 Against Blue and Green Mold of Citrus

A yeast strain was tested for its antagonistic activity against blue mold (Penicillium italicum) and green mold (Penicillium digitatum) of citrus fruit in bean sprout juice agar (BSJDA) medium. The strain (34-9) was identified as Kloeckera apiculata and showed the highest antagonistic activity against citrus blue mold and green mold on pair-culture against P. italicum and P. digitatum of citrus and on wounded citrus fruit. There was no antagonistic activity of fermentated filtrate and after sterilization. Observation by scanning electron microscopy revealed attachment of the yeast cells to the pathogen hyphae, indicating that the high antagonistic activity of the yeast may be contributed by the competition for space and nutrients and /or involvement of direct antagonist of the yeast on the fungus.