苏云金芽胞杆菌与绿僵菌对椰心叶甲的协同控制作用

Synergism between Bacillus thuringiensis and Metarhizium anisopliae against Brontispa longissima

测定了3个苏云金芽胞杆菌(Bacillus thuringiensis,Bt)菌株F6、NBT-18、Rt184与绿僵菌(Metarhizium ani-sopliae)菌株HK4复配剂对椰心叶甲致死作用。结果表明,3株Bt菌株对绿僵菌控制椰心叶甲的效果都有不同程度增强。在HK4孢子含量为106个/mL时,F6与HK4、NBT-18与HK4的复配剂处理椰心叶甲,5 d后死亡率分别达71.67%、61.35%,与单独用HK4分生孢子处理(死亡率为30.71%)相比,具有显著差异;而Rt184和HK4复配剂处理的死亡率与HK4单独处理无显著差异。在HK4孢子含量为107个/mL时,3种复配剂处理椰心叶甲5 d后,死亡率分别为82.74%、83.07%、68.61%,均与绿僵菌HK4单独处理(死亡率61.49%)有显著差异;且3个Bt菌株均能使绿僵菌HK4菌株侵染椰心叶甲的致死时间提前。

To investigate the synergistic effect between Bacillus thuringiensis and iVletarhiziwn anisopliae, three B. thuringiensis strains F6, NBT-18 and Rt184, were respectively mixed with M anisopliae strain HK4 for control of Brontispa longissirna （Gestro）. The bioassay results showed that all of the Bt strains F6, NBT-18 and Rt184 synergized with IVL anisopliae HK4 to some extent. When the concentration of M.. anisopliae HK4 was 10^6 conidia/mL, the mortality of B. longissima inoculated with the mixture of F6 and HK4 and that of NBT-18 and HK4 was 72% and 61%, respectively, after five days, significantly different from that treated with HK4 only （30%）, but there was no significant difference between the mortality caused by Rt184 mixed with or without HK4. When the concentration of M. anisopliae HK4 was 10^7 conidia/mL, the mortality of B. longissima treated with the three mixtures was 82%, 83% and 68%, respectively, after five days, all significantly different from that treated with HK4 only. When M. anisopliae was combined with Bt strains, the lethal time of B. longissima was shortened.