Relationship of Starvation and Critical Weight on Final Moult in the Desert Locust, Schistocerca gregaria

Abstract

Effect of starvation on last instar nymphs on final moult have been investigated in the both the
phases of the desert locust, Schistocerca gregaria (Forskal) (Orthoptera Acrididae). In gregarious
phase feeding to newly moulted fifth instar nymphs up to four days resulted 100 % mortality of 5th
instar in both male and female nymphs, whereas nymphs fed upto fifth day after initial moulting,
achieved weight 0.915± 0.0716 g in male and 1.255 ± .0870 g in female moulted into adult stage. In
solitary phase fifth instar nymphs required initial feeding of 2 days needed to achieve critical weight
0.97 ± 0.1094 g in male and 1.52 ± 0.01736 g in female to moulting into adult male and female. The
present investigation suggest that the gregarious fifth instar individuals while marching if they need
food for five days to metamorphose into adult, whereas solitary require 2 day of food to reach the
stage where resultant individual is adult.
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