The potential of <i>Chrysopa carnea</i> as a biological control agent of <i>Myzus persicae</i> on glasshouse chrysanthemums

Abstract

SUMMARY Larvae of C. carnea lived for 13‐4 days at 21·1°C and consumed an average of 385 second‐instar Myzus persicae or 425 Aphis gossypii. At 15·5°C the larval lifespan was 29·5 days though the consumption of M. persicae was hardly affected. M. persicae developing on glasshouse chrysanthemum plants were eliminated by the introduction of 1‐day‐old larvae at aphid: chrysopid ratios up to 50:1; third‐instar larvae achieved control at a ratio of 200:1. At very low aphid densities control was less effective. Control by C. carnea of aphid populations developing on glasshouse chrysanthemums can be predicted mathematically.