LIFE-HISTORY VARIATION IN CHRYSOPERLA-CARNEA - IMPLICATIONS FOR REARING AND STORING A MEXICAN POPULATION

A population of Chrysoperla carnea from San Pedro, Coahuila, Mexico, s howed phenological responses that differ from those of previously stud ied North American biotypes. Short daylengths that induce diapause in other biotypes resulted in low incidences of diapause in the San Pedro population. Diapause induction required a decrease in daylength (from long to short days). Constant long days produced variable reproductiv e responses, whereas an increase in daylength (from short to long day) resulted in high incidences of reproduction. Providing prey to adults that had been reared under short days consistently increased the inci dences of reproduction. Storage of either diapausing or nondiapausing adults at low temperature (5 degrees C) for 13 weeks yielded better su rvivorship and reproductive performance than in unstored (24 degrees C ) controls. For efficient production, the San Pedro population of C. c arnea may be reared either with an increase in daylength or with the r egular intervention of a storage period. To induce diapause in individ uals destined for storage, larvae may be reared under long-day photope riod and the prepupae transferred to short days. (C) 1997 Academic Pre ss.