Utilisation of food by Zonocerus variegatus (L.) (Orthoptera: Pyrgomor phidae)

Abstract

AbstractIndividuals and groups of adults of Zonocerus variegates (L.) were fed on various food-plants. Somatic growth, maturation and reproduction were all faster in group-fed insects than in isolated ones. Dry-season insects grew faster and produced greater numbers of egg pods than did wet-season ones. Short-winged insects developed faster than long-winged ones. Zonocerus that fed on cassava (Manihot esculenra) had a shorter somatic growth period and produced greater numbers of egg pods than insects that fed on any other foods. Cassava-fed Zonocerus had a greater efficiency of conversion of digested food to body substance, particularly during oocyte growth, than similar insects given other foods. Food plants such as Citrus and A spilia were inefficiently utilised, and often compensatory increases in consumption occurred. The success of the large dryseason population of Zonocerus in southern Nigeria is probably due to the increase in cassava cultivation.