文献类型： 外文期刊

作者： Kaur, Gagandeep ¹ ; Guo, Jianguo ¹ ; Brown, Sebe ³ ; Head, Graham P. ⁴ ; Price, Paula A. ⁴ ; Paula-Moraes, Silvana; ¹ ;

作者机构： 1.Louisiana State Univ, Dept Entomol, Agr Ctr, Baton Rouge, LA 70803 USA

2.Gansu Acad Agr Sci, Inst Plant Protect, Lanzhou 730070, Gansu, Peoples R China

3.Louisiana State Univ, Agr Ctr, Winnsboro, LA 71295 USA

4.Monsanto Co, St Louis, MO 63167 USA

5.Univ Florida, UF IFAS West Florida Res & Educ Ctr, Jay, FL 32565 USA

6.USDA ARS, Crop Genet & Breeding Res, Tifton, GA 31739 USA

关键词： Corn earworm; Cry1A.105/Cry2Ab2 resistance; Bt maize; Resistance management

期刊名称：JOURNAL OF INVERTEBRATE PATHOLOGY （ 影响因子：2.841； 五年影响因子：3.368 ）

ISSN： 0022-2011

年卷期： 2019 年 163 卷

页码：

收录情况： SCI

摘要： The corn earworm, Helicoverpa sea (Boddie) (Lepidoptera: Noctuidae), is a major target pest of pyramided Bt maize and cotton in the U.S. In 2017 and 2018, notable ear damage and larval survival of H. sea were observed on pyramided Cry1A.105/Cry2Ab2 maize in some fields in northeast Louisiana, U.S. The objective of this study was to determine if the field control problem was due to resistance development to the Bt proteins in plants. A total of 15 H. zea populations were collected from Bt and non-Bt maize plants in 2017 and 2018 in multiple locations in Louisiana, Florida, and Georgia. Diet-overlay bioassays showed that LC(50)s of Cry1A.105 and Cry2Ab2 for populations collected from the areas with control problems in northeast Louisiana were as much as > 1623- and 88-fold greater than that of a susceptible strain, respectively. In addition, two field trials in 2018 validated that CrylA.105/Cry2Ab2 maize failed in managing natural H. sea populations, while Bt maize containing Vip3A was effective in northeast Louisiana. Results of the study documented that the observed field control problems of Cry1A.105/Cry2Ab2 maize against H. sea in northeast Louisiana were due to resistance development of the insect to the Bt proteins in plants. This is the first documentation of field-evolved resistance to pyramided Bt maize in a target insect species in southern U.S. However, susceptibility levels to Cry1A.105 and Cry2Ab2 varied greatly among populations collected from the three states, suggesting uneven distributions of the resistance in the region.