Effects of Cholesterol on Growth and Development of the Aster Leafhopper, Macrostele fascifrons (STAL) (Hemiptera : Deltocephalidae)

Abstract

Requirement of the aster leafhopper, Macrosteles, for cholesterol was studied by feeding on a holidic diet. Although the absence of cholesterol from the diet did not markedly affect the growth of the leafhopper nymphs derived from plants from first to fifth instar in the first generation, cholesterol was found important to their imaginal moult and the growth of their progeny. Newly hatched nymphs produced by the cholesterol-deficient mothers were unable to survive and to grow normally on the cholesterol-free diet. The optimal concentration of cholesterol for rearing consecutive generations ranged from 2.5 to 5.0 mg/100ml of diet. Lower concentrations could support nymphal growth only. It was concluded from the feeding experiments that cholesterol was an indispensable component in the leafhopper diet. Continuous rearing with the lecithin-containing diet seemed attributable to the presence of growth factor(s) as an impurity, probably cholesterol. Linoleic and linolenic acids did not substitute for the cholesterol requirement for continuous culture.