Larval rearing density effects on lipid reserves and wing-loading in fail armyworm adults (Lepidoptera: Noctuidae)

摘要

abstract_textpA laboratory study was conducted to determine if a high larval rearing density produces premigrant traits in the fall armyworm, Spodoptera frugiperda (J. E. Smith), and if these traits can be used as criteria for separating non-premigrant from premigrant groups. The putative premigrant traits of high lipid reserves and low wing-loading were measured in newly emerged adult fall armyworm. An increase in rearing density significantly increased adult whole-body lipid content, but the increase may be due, in part, to enhanced nutrition through cannibalism. Although larval rearing density did not affect wing-loading, the fall armyworm as a migrant species showed lower than theoretically expected wing-loading values. The lack of density-dependent increases in lipid reserves and the lack of density effects on adult activity, developmental time, and size (documented herein and in previous studies) may indicate that a premigrant phase induced by high larval density does not exist in the fall armyworm./p/abstract_text