番茄灰霉病拮抗菌K2的筛选及鉴定

摘要

One antagonism strain of bacteria called K-2 is separated from soil,which can strongly antagonize Botrytis cinerea .After 5-days’culture plate confrontation experiment be-tween K-2 and Botrytis cinerea JY1-4,obvious bacteriostatic belt appears with the bacteriosta-tios ratio of 66.1 9%,and 15 days later stable antibacterial effect can still remains.Fermentation liquor of K-2 has significant inhibitory effect on spore germination of Botrytis cinerea JY1-4 with the bacteriostatios ratio of 100%.The mechanism of K-2 against germs performs that it can make hypha deform distorted and restrain bacteria conidium germination.The colonization experiment in soil results shows that in the field of in-situ conditions the antagonist K-2 will re-duce survival rates for the influence of the indigenous microorganisms,but it still has sustained and stable potential of antagonism ability.%从土壤中分离出一株对蕃茄灰霉病菌(Botrytis cinerea )有较强拮抗能力的细菌 K 2。通过平板对峙培养法对其抑菌效果进行测定,结果表明：1)培养5 d 后,K 2菌落周围产生明显的抑菌带,对 Botrytis cinerea 的抑菌率达66.19%,培养15 d 后仍保持稳定的抑菌效果；2)K 2的发酵原液对 Botrytis cinerea 孢子萌发具有显著的抑制作用,抑制率为100%；3)K 2对病菌的作用机制表现为使病菌菌丝畸形、菌丝扭曲、抑制病菌分生孢子的萌发；4)土壤定殖试验表明,拮抗菌 K 2会受到土著微生物的影响降低存活率,但仍具有在土壤中存活并较长时间保持拮抗能力的潜力。