2株拮抗生防菌对油茶炭疽病多种病原菌的抑菌活性及防效

Antibacterial activity and control effect of two antagonistic biocontrol bacteria against various pathogens of Camellia oleifera anthracnose

【目的】精准防治油茶炭疽病,为开发油茶炭疽病生物防治菌剂,获取更加高效、安全的油茶炭疽病生物防治技术提供参考。【方法】以枯草芽孢杆菌Bacillus subtilis YL13、球孢链霉菌球孢亚种Streptomyces globisporus subsp.Globisporus F10为供试拮抗菌,研究其发酵滤液对5种油茶炭疽菌(胶孢炭疽菌Colletotrichum gloeosporioides、果生炭疽菌C.fructicola、暹罗炭疽菌C.siamense、山茶炭疽菌C.camelliae、哈锐炭疽菌C.horii)生长的影响,测定其发酵滤液对优势炭疽菌胶孢炭疽菌和果生炭疽菌的效价,并在离体叶片上对油茶炭疽病进行防效研究。【结果】YL13发酵滤液对5种炭疽菌的抑制效果由强到弱依次为胶孢炭疽菌、暹罗炭疽菌、果生炭疽菌、哈锐炭疽菌、山茶炭疽菌,F10发酵滤液对5种炭疽菌的抑制效果由强到弱依次为胶孢炭疽菌、果生炭疽菌、哈锐炭疽菌、暹罗炭疽菌、山茶炭疽菌。2种发酵滤液对胶孢炭疽菌的抑制效果均为最佳,抑制率分别为83.46%、62.20%,对山茶炭疽菌的抑制率均为最低,分别为49.15%、30.99%。YL13发酵滤液对胶孢炭疽菌和果生炭疽菌的效价分别约为100、400倍,F10发酵滤液对胶孢炭疽菌、果生炭疽菌的效价均为40倍。当2种拮抗菌的发酵滤液稀释到一定浓度后,抑菌率均发生了不同程度的降低。随着稀释倍数的增大,YL13发酵滤液的抑菌活性降低速率远超过F10。在离体叶片上拮抗菌株对油茶炭疽病均有一定的防治效果,在接种YL13菌株2 d后再接种病原菌的预防效果最佳,达到了60%,F10对油茶炭疽病的预防和治疗均是拮抗菌与病原菌相隔1 d接种效果最佳,防治效果均达到了70%。【结论】2株生防菌对不同油茶炭疽病菌的拮抗效果存在一定的差异,但均具有明显的抑制作用。在离体叶片上,2种生防菌对油茶炭疽病均有良好的防治效果,可以用于生物防治药剂的开发。

【Objective】The purpose is to accurately prevent and control Camellia anthracnose,provide a reference for the development of biological control agents for Camellia oleifera anthracnose,and obtain more efficient and safe biological control techniques for C. oleifera anthracnose.【Method】YL13 and F10 were used as tested antagonistic antibacterial. The effect of the fermentation filtrate on the growth of 5 species of C. oleifera anthracnose including Colletotrichum gloeosporioides, Colletotrichum fructicola, Colletotrichum siamense, Colletotrichum camelliae and Colletotrichum horii were studied. The potency of two dominant Colletotrichum spp., C. gloeosporioides and C. fructicola, were determined, and the control effect of Colletotrichum spp. on detached leaves of C. oleifera was studied. 【Result】The inhibitory effects of YL13 fermentation filtrate on 5 kinds of Colletotrichum spp. from strong to weak were as follows: C. gloeosporioides, C. siamense, C. fructicola , C. horii and C. camelliae. The inhibitory effects of F10 fermentation filtrate on 5 kinds of Colletotrichum spp. from strong to weak were as follows: C. gloeosporioides, C. fructicola, C. horii ,C. siamense and C. camelliae. Both fermentation filtrates had the best inhibitory effects on C. gloeosporioides, with the inhibition rates being 83.46% and 62.20%, respectively, and the inhibition rates on C. camelliae were the lowest, being 49.15% and 30.99% respectively. The titer of YL13 to C. gloeosporioides and C. fructicola was about 100 times and 400 times respectively. The titer of F10 to C. gloeosporioides and C. fructicola was 40 times. When the two antagonistic fermentation filtrates were diluted to a lower concentration, the inhibition efficiency decreased to varying degrees. With the increase of the dilution, the inhibition activity of YL13 decreases much faster than F10. Both YL13 and F10 had certain effects on preventing anthracnose on separated leaves. If YL13 was inoculated two days earlier than the pathogen, the inhibition efficiency reached the best, which was 60%. Whether prevention or treatment, F10 and pathogen inoculated one day apart, the inhibition efficiency reached the best, which was 70%.【Conclusion】The antagonistic effects of YL13 and F10 on Colletotrichum spp. were different, but both of them have obvious inhibitory effects. YL13 and F10 have good inhibition efficiency on anthracnose of C. oleifera in vitro leaves, which can be used for the development of biological control agents.