Effects of larval density on the development and reproduction of Athetis lepigone
Author of the article:LI Yan1, 2** JIANG Xing-Fu2*** ZHANG Lei2 CHENG Yun-Xia2 LIU Yan-Qun1 LUO Li-Zhi2
Author's Workplace：1. College of Bioscience and Biotechnology, Shenyang Agricultural University, Shenyang 110866, China;2. State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Beijing 100193, China
Key Words：Athetis lepigone, larval density, growth and development, reproduction
Abstract： [Objectives] To investigate the effects of larval density on the development, reproduction, and population growth of Athetis lepigone. [Methods] The growth, development, and reproduction of A. lepigone were examined by rearing larvae at densities of 1, 5, 10, 20, and 30 larvae/750 mL. [Results] The developmental duration of different instars, all larvae, pupae, survival rate from larvae to pupae, pupal weight and adult reproduction of A. lepigone were significantly affected by larval density. The duration of larval development was lowest at a density of 10 larvae/750 mL (18.27 d) but significantly increased with increasing larval density. The survival rate from larvae to pupae decreased with larval density and was only 39.37 % at a density of 30 larvae/750 mL. Pupal developmental duration was prolonged with increasing larval density, except at a density of 10 larvae/750 mL. Pupal weight and the number of eggs laid per female significantly reduced with increasing larval density. The longevity of both sexes was greatest at 10 larvae/750 mL, but less at either lower or higher density. Life table analysis suggested that larval density significantly affected the population growth index, being highest at a density of 5 larvae/750mL and significantly lower when the larval density was too high. [Conclusion] The results suggest that larval density is one of the major ecological factors influencing the population dynamics in A. lepigone.