CHRYSOPERLA-EXTERNA (NEUROPTERA, CHRYSOPIDAE) - LIFE-HISTORY AND POTENTIAL FOR BIOLOGICAL-CONTROL IN CENTRAL AND SOUTH-AMERICA

The predacious insect Chrysoperla externa (Hagen) has a number of traits that make it amenable to mass-rearing and use as a biological control agent. Developmental and reproductive rates were relatively high and directly related to temperature between 15.6 and 26.7-degrees-C. Survival also was high throughout this temperature range. Lower thermal thresholds for development (t) of all immature stages fell between 11 and 12.5-degrees-C, and the K value for total development was 320 heat degree-days above 11.8-degrees-C. At 21.1-degrees-C, oviposition averaged 284 eggs during the first 30 days. Variability in diapause induction occurred within and among populations: a proportion of the Chilean and the Brazilian populations went into diapause under a short daylength, whereas no diapause occurred in the Honduran population. Chrysoperla externa appears well suited as a biological control agent for use in pest management programs in tropical and temperate regions of Central and South America. (C) 1994 Academic Press, Inc.