THE LIFE-HISTORY OF RODOLIA-ICERYAE JANSON (COL, COCCINELLIDAE) AND THE POTENTIAL FOR USE IN INNOCULATIVE RELEASES AGAINST ICERYA-PATTERSONI NEWSTEAD (HEM, MARGARODIDAE) ON COFFEE

Rodolia iceryae Janson is a predator of Icerya pattersoni Newstead, wh ich is a pest of coffee in Kenya. It was studied under controlled cond itions at 27 degrees C and 70% relative humidity. The beetle mates 1-2 days after emergence. Eggs were laid in very close association with t he host suggesting that R. iceryae was well adapted to exploit I. patt ersoni. The duration of immature development was 36.3 days and adult l ongevity ranged from 15 to 74 days. Measurements of the sizes of diffe rent developmental stages were also taken. The age-specific fecundity and life table statistics under laboratory conditions were determined as follows: R(0), 50.160; G, 61.175; r(m), 0.064; lambda, 1.067; and p opulation doubling time, DT, 10.830 days. These statistics suggest tha t the beetle may be an effective agent as it has the potential to mult iply much faster than its host. The host specificity of R. iceryae is also discussed in relation to other Rodolia spp. and it is concluded t hat the beetle will be restricted to feeding on I. pattersoni.