鲜食核桃贮藏期主要真菌病害分离及抑制

rDNA-ITS sequence analysis and bacteriostasis of fungal pathogens in fresh walnuts during storage

对贵州省特色品种“纸皮核桃”贮藏期（贮藏温度10～25℃）果实表面的病原菌进行分离与鉴定，测定病原菌rDNA-ITS序列，确定菌属；初步进行病原菌的生物、化学抑菌试验，为鲜核桃病害防治提供依据。采用病原菌形态鉴定与rDNA—ITS鉴定相结合的方法，确定引起鲜食核桃霉烂的病原菌种类；通过不同浓度生物、化学抑菌剂探索其对不同菌种抑菌效果。结果表明，从贮藏期霉烂的鲜核桃上共分离出4株病原菌，主要为毛霉属（Mucor）、镰孢菌属（Fusarium）、曲霉属（Aspergillus），抑茵试验表明纳他霉素对4种菌抑菌效果最好，解淀粉芽孢杆菌发酵液和双乙酸钠、山梨酸钾抑菌效果大体一致。引起“纸皮核桃”贮藏期果实霉烂的主要菌种为Mucorcircinelloides、Fusariumsolani、Aspergillus flavus、Aspergillusniger；纳他霉素能有效抑制“纸皮核桃”贮藏期主要微生物，解淀粉芽孢杆菌作为生防茵具有很好前景。

The fungal pathogens of ＂Zhipi＂ fresh walnuts were isolated during storage and identified by rDNA-ITS sequences analysis. Car- ried out Bacteriostasis experiment. With rDNA-ITS analysis and morphological characterization, the species of Fungal pathogens were differentiated and identified. Bacteriostatic effect was assessed by Bacteriostasis experiment. Three strains were identified, e. g. Mucor , Fusarium , and Aspergillus. Fusarium and Mucor was the dominant species. The bacteriostatic effect of Natamycin was the best, and the bacteriostatic effect of the fermented liquid from Bacil- lus amyloliquefaciens was the same with these of sodium diacetate and potassium sorbate. Fusarium, Mucor, and Aspergillus weremainly fungal pathogens of ＂Zhipi＂ fresh walnuts. Natamycin could effectively inhibit the mainly fungal pathogens from fresh walnuts surface. The Bacillus arrlyloliquefaclens as bio-control bacteria had a great prospect.