›› 2015, Vol. 58 ›› Issue (1): 45-52.

• RESEARCH PAPERS • Previous Articles     Next Articles

Hardiness characteristics of the overwintering generation of Helicoverpa armigera (Lepidoptera: Noctuidae) feeding on Bt cotton and corn

CAO Jing1, 2 , OUYANG Fang2, GE Feng2, YANG Zhong-Xia1, *, XIAO Tie-Guang1, *   

  1. (1. College of Plant Protection, Hunan Agricultural University, Changsha 410128, China; 2.State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China)
  • Online:2015-01-20 Published:2015-01-20

Abstract: 【Aim】 From the perspective of the farmland landscape in north China composed of Bt cotton and corn, the research aims to explore the influence of different hosts on hardiness of the overwintering generation of  Helicoverpa armigera. 【Methods】 H. armigera  larvae were inoculated on Bt cotton and corn in the field of scientific base in Langfang, Heibei, 2013. During this period, the pupation rate, diapause rate and emergence rate of overwintering pupae of H.armigera feeding on different types of crops were detected and compared. Indoors, H. armigera  larvae were fed on buds of cotton and fresh corn kernels and then the hardiness of diapausing pupae and non-diapausing pupae were compared in terms of the fresh weight, dry weight, fat content, glycogen content, and contents of low molecular substances. 【Results】 It was found that the diapausing pupae of  H. armigera  feeding on corn had obviously higher dry weight(117.5 mg vs 56.6 mg), fat content (457.2 μg/mg DW vs 239.6 μg/mg DW) and trehalose content(86.45 μg/g vs 13.87 μg/g), and lower freezing point (-10.2℃ vs -6.5℃) than the diapausing pupae feeding on Bt cotton (P<0.05). 【Conclusion】 The results indicate that corn is the ideal host for H. armigera to live through the winter in the field. According to the historical data, the planting area of corn has been increasing in recent years, which will facilitate the successful overwintering and population expansion of H. armigera. Therefore, it is significant to control H. armigera in corn field.

Key words: Helicoverpa armigera, transgenic cotton, corn, diapausing pupae, nondiapausing pupae, hardiness, trehalose