球孢白僵菌对四种十字花科蔬菜害虫的兼控潜力评价

Pathogenicity of Beauveria bassiana isolate to cruciferous vegetable insect pests.

研究了分离自小猿叶甲的一株球孢白僵菌(Beauveria bassiana(SCAU-BB01D))对十字花科蔬菜4种非目标害虫烟粉虱Bemisia tabaci、小菜蛾Plutella xylostella、黄曲条跳甲Phyllotreta striolata和菜缢管蚜Lipaphis erysimi的致病能力.结果表明,在实验室条件下,该菌株对以上4种害虫均有不同程度的侵染力.1×108孢子/mL的白僵菌悬浮液对1,2,3,4龄烟粉虱若虫的侵染率分别为84.88,86.81,55.94和38.78%;对小菜蛾2,3和4龄幼虫的侵染率为67,59和44%;对黄曲条跳甲幼虫和成虫分别为63%和60%;对菜缢管蚜成蚜和若蚜的侵染率分别为44%和35%.通过机率值分析,得出该菌株对烟粉虱1～4龄若虫的LT50分别为4.14,3.78,6.24和7.59 d;对小菜蛾2～4龄幼虫的LT50分别为7.29,8.16和9.82d;对黄曲条跳甲成虫和幼虫的LT50分别为11.22和8.11d;对菜缢管蚜成蚜和若蚜的LT50分别为11.01和12.15 d.说明该球孢白僵菌菌株对烟粉虱、小菜蛾和黄曲条跳甲3种非目标害虫具有一定的兼控作用,在蔬菜害虫的生物防治中具一定的应用潜力.

An isolate of Beauveria bassiana （SCAU-BB01D） derived from Phaedon brassicae was found to infect four non-target cruciferous vegetable insect pests, Bemisia tabaci, Phyllotreta striolata, Plutella xylostella and Lipaphis erysimi, in the laboratory. Immersion of B. tobaci in the fungal suspension of 1 × 10^8 conidia/mL caused 84.88, 86.81,55.94 and 38.78% of the 1 - 4 instar nympls dead, and 67,59 and 44% of the 2 - 4 instar larvae of in P. xylostella dead respectively. The mortalities of P. striolata adult and larva attributed to fungal infection were 63 % and 60% ,while the mortalities of L. erysimi adult and nymph caused by the fungal infection were only 44% and 35% , The probit analysis showed that the LTs0 values of B. bassiana were 4.14,3.78; 6.24 and 7.59 d to B. tabaci; 7.29,8.16 and 9.82 d to the 2 - 4 larvae of P. xylostella; 11.22 and 8.1 l d to P. striolata adult and larva; 11.01 and 12.15d to L. erysimi adult and nymph, respectively. It showed that B. bassiana had a potential in control of cruciferous vegetable insect pests.