Development of Spodoptera exigua (Hübner) (Lepidoptera: Noctuidae) on Different Feed Plants

Abstract

       The development and life cycle of the beet armyworm, Spodoptera exigua (Hübner), were determined in the laboratoryusing six feed plants: welsh onion ( Allium fistulosum); amaranth (Amaranthus viridis) ; mustard greens (Brassica integrifolia); mung bean (Vigna radiata); cabbage ( Brassica oleracea capitata); and turmeric (Curcuma longa). The life cycle of S. exigua was shortest on amaranth (24.2 days) and longest on turmeric (34.7 days). Feed plants did not significantly affect the percentage of egg hatching or pupal survival. However, larval survival differed among feed plants, being highest on amaranth (87.6%) and lowest on turmeric (50.0%). The highest percentage of female progeny was recorded from S. exigua reared on welsh onion (46.7%) and the lowest for larvae reared on turmeric (36.1%). The fecundity of S. exigua females ranged from 174.3 eggs on turmeric to 453.8 eggs on amaranth. Within each feed plant, the increased pupal weight resulted in increased fecundity. It means that the fecundity was significantly related to the female pupal weight of S. exigua reared on test feed plants (r = 0,883 - 0,965).