Laboratory Rearing of Rhynchophorus Cruentatus and R. Palmarum (Coleoptera: Curculionidae)

Abstract

Larvae of Rhynchophorus cruentatus (F.) of variable starting weights gained weight when incubated at 23@* C for 21 days in sugarcane stems. R. cruentatus was reared through one generation on sugarcane stems with a mean generation time of >212 days at 23@* C. Comparisons were made with the syncarpium of pineapple as a growth medium for R. cruentatus at 23@* C and 28@* C for 25 days. Mean fecundity of R. cruentatus on pineapple was not significantly different at the two temperatures or between newly-emerged field-collected adults or those reared on sugarcane. Larvae from the pineapple syncarps at 28@* C were significantly heavier than those reared at 23@* C for 25 days. Complete development of R. cruentatus did not occur on pineapple. From these preliminary studies a method for laboratory rearing R. cruentatus was developed. Single pairs of newly-emerged females and males were confined to individual pineapple syncarps for >25 days at 28@* C. Resultant larvae were individually transferred into sugarcane stems to complete metamorphosis. Using a pineapple-sugarcane diet, R. cruentatus was reared through five successive generations in Florida and R. palmarum (L.) was reared through one generation in Trinidad.