›› 2015, Vol. 58 ›› Issue (9): 981-988.

• RESEARCH PAPERS • Previous Articles     Next Articles

Oviposition strategy of the camellia weevil, Curculio chinensis (Coleoptera: Curculionidae), on oil tea (Camellia meiocarpa)

LI Zhi-Wen1, HE Li-Hong1, YANG Liu-Jun1, HE Bin2, ZENG Ai-Ping1,*   

  1. (1. Hunan Provincial Key Laboratory for Biology and Control of Plant Diseases and Insect Pests, Institute of Insect, Hunan Agricultural University, Changsha 410128, China; 2. Forestry Bureau of Ziyang District Yiyang City Hunan Province, Yiyang, Hunan 413001, China)
  • Online:2015-09-20 Published:2015-09-20

Abstract: 【Aim】 The camellia weevil,  Curculio chinensis Chevrolat, is an important pest attacking fruits of the oil tea  Camellia, an endemic genus to China, and causes tremendous fruit drop of its host plants. To reveal the oviposition strategy of  C. chinensis, we explored the relationships between oviposition activity of C.chinensis  and the traits of its host fruit. 【Methods】 During the most active oviposition season, 960 fruits of  C. meiocarpa  were collected randomly from an oil tea ( Camellia meiocarpa) farm. The number of punctures and clutch size of C. chinensis, as well as the weight, length and diameter of each fruit were measured, and the difference of fruit size among oviposition-punctured fruits, feeding-punctured fruits and non-damaged fruits was analyzed through one-way ANOVA (LSD), and the effect of fruit traits on feeding and oviposition activity was analyzed through linear regression model. A choice test of the pest on fruits size was carried out, and the difference of fruit size between selected and non-selected fruits was analyzed by paired-samples t test. 【Results】 Oviposition-punctured fruits of C. meiocarpa were significantly larger than feeding-punctured fruits, while the latters were significantly larger than non-damaged fruits in terms of weight, length, diameter, and volume (P<0.01). The number of punctures, clutch size and weevil parasitism rate were positively correlated with fruit size (P<0.01), suggesting that parental weevils prefer larger fruits to feed and oviposite. The female adults of C. chinensis showed obvious preference to larger fruits when the difference of fruit size between the two fruits tested was significant, and heavily damaged fruits were significantly larger than lightly damaged fruits in terms of length and diameter after infection by female adults of C. chinensis for 12 h. Independent of host fruit traits, C. chinensis laid one egg in each puncture hole. 【Conclusion】 C. chinensis adults prefer larger fruits to feed, which supports the optimal foraging theory. C. chinensis adults also prefer larger fruits to oviposite. The small clutch size would reduce intraspecific competition C. chinensis between offsprings and increase the probability of larval development, and thus they would be more likely to successfully exit from host fruits. We infer that the single egg laying behavior in C. chinensis is a riskspreading strategy, an adaptation toward limited food resource.

Key words: Curculio chinensis, Camellia meiocarpa, fruit size, clutch size, choice test, oviposition strategy