Field-evolved resistance to Bt toxin Cry1Ac in the pink bollworm, Pectinophora gossypiella (Saunders) (Lepidoptera: Gelechiidae), from India
Field-evolved resistance to Bt toxin Cry1Ac in the pink bollworm, Pectinophora gossypiella (Saunders) (Lepidoptera: Gelechiidae), from India
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DOI：
10.1002/ps.2127
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发表时间：
2011-08-01
影响因子：
4.1
通讯作者：
Gujar, Govind T.
中科院分区：
文献类型：
--
作者：
Dhurua, Sanyasi;Gujar, Govind T.
背景：棉铃虫是危害棉花最严重的害虫之一。产生Bt毒素Cry1Ac或Cry1Ac与Cry2Ab2组合的转基因棉花已被有效地用于防治这种害虫。然而，其他一些昆虫在田间已经进化出对Bt毒素的抗性。在2007-2008和2008-2009两季，对印度的粉棉铃虫种群进行了调查，以评估它们对Cry1Ac和含有Cry1Ac和Cry2Ab2的种子粉的反应。结果：研究结果表明，到2008年，印度西部古吉拉特邦Amreli地区的非bt棉花种群对Cry1Ac的抗性已经进化。2008年产自Amreli的昆虫5日龄幼虫的Cry1Ac致死浓度中位数（LC50）明显高于在印度4个地点测试的任何其他田间种群。对于Cry1Ac， 2008年来自Amreli的菌株的平均LC50比最易感人群高44倍。然而，对于主要含有Cry2Ab2的Bollgard II种子粉，2008年Amreli群体的易感程度仅略低于最易感群体。结论：本文报道的数据构成了棉铃虫对Cry1Ac田间进化抗性的第一个证据。这一初步证据促使在2009-2010生长季节进行了更广泛的评估，证实了Amreli对Cry1Ac的田间进化抗性。缺乏对Cry2Ab2的交叉抗性表明，产生这种毒素的植物可能比只产生Cry1Ac的植物对抗性群体更有效。(C) 2011年化学工业学会
BACKGROUND: The pink bollworm is one of the most destructive pests of cotton. Transgenic cotton producing Bt toxin Cry1Ac or a combination of Cry1Ac and Cry2Ab2 has been used effectively against this pest. However, some other insects have evolved resistance to Bt toxins in the field. During the 2007-2008 and 2008-2009 seasons, pink bollworm populations in India were surveyed to evaluate their responses to Cry1Ac and seed powder containing Cry1Ac and Cry2Ab2.RESULTS: The results provide evidence that resistance to Cry1Ac had evolved by 2008 in a population sampled from non-Bt cotton in the Amreli district of Gujarat in western India. The median lethal concentration of Cry1Ac for five-day-old larvae (LC50) was significantly higher for insects derived in 2008 from Amreli than for any of the other field populations tested from four locations in India. For Cry1Ac, the mean LC50 for the strain derived from Amreli in 2008 was 44 times higher than for the most susceptible population. However, for seed powder of Bollgard II containing primarily Cry2Ab2, the 2008 Amreli population was only slightly less susceptible than the most susceptible population.CONCLUSIONS: The data reported here constitute the first evidence of field-evolved resistance of pink bollworm to Cry1Ac. This initial evidence spurred more extensive evaluations during the 2009-2010 growing season, which confirmed field-evolved resistance to Cry1Ac in Amreli. The lack of cross-resistance to Cry2Ab2 suggests that plants producing this toxin are likely to be more effective against resistant populations than plants producing only Cry1Ac. (C) 2011 Society of Chemical Industry