4种喷雾助剂对解淀粉芽胞杆菌Lx-11的增效作用及安全性评价

Synergistic effect and safety evaluation of four kinds of spray adjuvants on Bacillus amyloliquefaciens Lx-11 strain

为提高解淀粉芽胞杆菌Lx-11悬浮剂对水稻白叶枯病的防治效果,通过研究添加4种喷雾助剂(有机硅、TM-10、卵磷脂和SY-6535)对解淀粉芽胞杆菌Lx-11含菌量的影响、药液的表面张力和接触角的变化、助剂对水稻生长的安全性影响等,并测定了添加助剂生防菌对白叶枯病的盆栽防治效果以及在水稻叶表定殖动态,最终筛选出适合的喷雾助剂。结果表明:添加卵磷脂的解淀粉芽胞杆菌Lx-11悬浮剂的含菌量显著降低;添加有机硅、TM-10和SY-6535均能有效降低悬浮剂的表面张力及其在水稻叶片上的接触角。安全性评价显示,有机硅、TM-10和SY-6535对水稻幼苗生长无影响。盆栽试验结果表明,添加TM-10和SY-6535后,解淀粉芽胞杆菌Lx-11悬浮剂(4.0×109cfu/mL)对水稻白叶枯病的防治效果达到57.70%和56.56%,显著高于未添加助剂的悬浮剂的防治效果;定殖试验结果表明,添加助剂后,解淀粉芽胞杆菌Lx-11在水稻叶表的定殖量也显著高于对照处理。

To improve the control efficacy of Bacillus amyloliquefaciens Lx-11 suspension concentrate on rice bacterial blight,four kinds of spray adjuvants(silicone,TM-10,lecithin,and SY-6535)were selected in this study and their effects on B.amyloliquefaciens Lx-11 bacterial content,the liquid’s surface tension,contact angle changes,and the safety of rice growth were evaluated.In addition,the control effect of Lx-11 strain against bacterial blight in the pot experiment and the colonization dynamics on rice leaf surface were determined for an applicable spray adjuvant.The results showed that the bacterial content of B.amyloliquefaciens Lx-11 is significantly declining when treated with lecithin among four spray adjuvants.Silicone,TM-10,and SY-6535 effectively reduce the surface tension of the suspension solution and the contact angle on rice leaves.The safety evaluation of rice showed that silicone,TM-10,and SY-6535 does not affect the growth of rice seedlings.The pot experiment results showed that the control efficacy of biocontrol bacteria Lx-11(4.0×10~9 cfu/mL)against bacterial blight reaches 57.70%and 56.56%after adding TM-10 and SY-6535,which was significantly higher than that of the suspension agent without adjuvants.The colonization experiment showed that the colonization of Lx-11 strain on the rice leaf surface is significantly higher after adding adjuvants than that of the control treatment.