The effect of food on the development and reproduction of 4 geographic populations of Ectropis oblique Prout
Author of the article:LIN Qiang1** ZHENG Ji-Shu1 LI Ping1 GAO Dong-Mei1 GUO Xiao1*** HAN Shuang2
Author's Workplace：The effect of food on the development and reproduction of 4 geographic populations of Ectropis oblique Prout
Key Words：Ectropis oblique, geographic population, tea leaves, life table parameters, feeding adaptability
Abstract： [Objectives] To provide a theoretical foundation for differentiated control strategies for different geographic populations of Ectropis oblique Prout. [Methods] Larval and pupal developmental duration, larval mortality rates and the intrinsic rate of increase of larvae collected from 4 geographic populations of E. oblique were investigated on young tea leaves, mature tea leaves and old tea leaves, under laboratory conditions. Specimens were collected from populations in Zhejiang Province, Hubei Province, Fujian Province and Jiangxi Province. [Results] Significant differences in larval and pupal developmental duration were found between populations. Larval and pupal development was shortest on mature leaves. Mortality of < 3rd instar larvae was highest (33%) on old tea leaves and lowest (15%) on young tea leaves. The number of eggs per female was highest (362.23 eggs) on young tea leaves and lowest on old tea leaves (56.67 eggs). There were no significant difference in the intrinsic rate of increase, net reproductive rate, doubling time or finite rate of increase of larvae from the four geographic populations on mature tea leaves (P>0.05). Significant difference among populations in all these variables were, however, apparent when larvae were kept on young, or old tea, leaves (P<0.05). Correlations between population life-history parameters and the main chemical constituents of tea leaves were clearly inconsistent between the 4 populations. 2 substances found in tea leaves had a significant impact on the Jiangxi and Hubei populations and 1 substance greatly affected the Zhejiang and Fujian populations of the E. oblique. [Conclusion] There were obvious differences in the ability of E.oblique larvae from 4 geographic populations to feed on young, mature and old, tea leaves. The Zhejiang population was the most adaptable in this regard and had the highest larval survival rate, number of eggs per female and net reproductive rate (R0) of the four populations. The Hubei population had the highest mortality rate and lowest net reproductive rate (R0) on old tea leaves and the Jiangxi population also displayed relatively high mortality and low fecundity when fed old tea leaves.