摘要
使用苏云金芽胞杆菌库斯塔克亚种(Btk)可湿性粉剂对小菜蛾进行继代汰选获得F80代和F100代抗性品系。通过分别测定Cry1Ab、Cry1Ac、Cry1Ah和Cry1Ca四种杀虫晶体蛋白对小菜蛾Btk抗性品系F80代和F100代的室内毒力,明确了小菜蛾Btk抗性品系对四种Bt杀虫晶体蛋白抗性发展规律。研究结果表明,汰选至F80代时,Cry1Ca对小菜蛾的毒力最高,LC_(50)约12.1 mg/L,其次为Cry1Ac,LC_(50)约47.7 mg/L;而汰选至F100代时,仍以Cry1Ca对小菜蛾的毒力最高,LC_(50)约21.4 mg/L,其次为Cry1Ab,LC_(50)约72.2 mg/L。与相对敏感品系相比,小菜蛾抗性品系对Cry1Ac的抗性发展较快(抗性倍数高达67.3~106.8倍),对Cry1Ab的次之(抗性倍数高达60.0~66.1倍),而对Cry1Ca和Cry1Ah的抗性发展较慢(抗性倍数分别为3.4~6.0倍和1.6~2.5倍)。以上结果说明,在主效杀虫基因为Cry1Ac的Btk药剂选择压力下,小菜蛾对四种Bt杀虫晶体蛋白的抗性发展速度差异较大,且Cry1Ac和Cry1Ab存在交互抗性风险。
The Bacillus thuringiensis(Bt)-resistant strains of Plutella xylostella(L.)were selected using a wettable powder formulation of Bt var.kurstaki(Btk)for 80 and 100 generations in the laboratory,respectively.The toxicities of four Bt-insecticidal crystal proteins(Cry1Ab,Cry1Ac,Cry1Ah,and Cry1Ca)against Btk-resistant and-susceptible strains of P.xylostella were determined using a standard leaf-dipping method.For the F80 generation of Btk-resistant strain,Cry1Ca had higher toxicity with a LC_(50) value about 12.1 mg/L than the other three Cry proteins,followed by Cry1Ac with a LC_(50) value about 47.7 mg/L.For the F100 generation of Btk-resistant strain,Cry1Ca still showed higher toxicity with a LC_(50) value about 21.4 mg/L than the other three Cry proteins,followed by Cry1Ab with a LC_(50) value about 72.2 mg/L.The Btk-resistant strains of P.xylostella showed quick development of resistance to Cry1Ac,with a resistance ratio(RR)increased from 67.3-fold to 106.8-fold when compared with the susceptible laboratory strain.The resistance to Cry1Ab was relatively low,with a RR value from 60.0-fold to 66.1-fold,and the resistance to Cry1Ca and Cry1Ah was even lower,with RR values of 3.4—6.0-fold and 1.6—2.5-fold,respectively.In conclusion,these results suggest that,under the selection pressure of Btk with a dominant gene of Cry1Ac,P.xylostella strains show significant differences in the development of resistance to four insecticidal crystal proteins,and that there is a potential risk of cross-resistance between Cry1Ac and Cry1Ab.
作者
符伟
唐涛
王培
王勇
尹丽
马明勇
张政兵
FU Wei;TANG Tao;WANG Pei;WANG Yong;YIN Li;MA Mingyong;ZHANG Zhengbing(Institue of Plant Protection,Hunan Academy of Agricultural Sciences,Changsha 410125,China;Hunan Plant Protection and Quarantine Station,Changsha 410005,China)
出处
《中国生物防治学报》
CSCD
北大核心
2022年第2期328-332,共5页
Chinese Journal of Biological Control
基金
国家重点研发计划(2017YFD0201200)
国家自然科学基金(31401775)。
关键词
小菜蛾
苏云金芽胞杆菌
杀虫晶体蛋白
生物测定
抗药性
Plutella xylostella
Bacillus thuringiensis
insecticidal crystal protein
bioassay
resistance
