EFFECT OF OVER-WINTERING AND INCUBATION TEMPERATURES ON ADULT EMERGENCE IN OSMIA-CORNUTA LATR (HYMENOPTERA, MEGACHILIDAE)

Cocoons of the potential orchard pollinator Osmia comuta were exposed to different over-wintering and incubation temperatures to see if adult emergence could be manipulated and bees could be induced to emerge in synchrony with almond bloom. Bees over-wintered in a warehouse in an almond-growing area emerged over a period of time longer than the blooming period of commercial almond orchards. Conversely, bees over-wintered in refrigerators completed emergence in less than a week. Longer over-wintering periods yielded shorter emergence periods, but lower over-wintering temperatures did not. Incubation of over-wintered cocoons for 24 h failed to consistently accelerate emergence. The shortest emergence periods were obtained when bees were over-wintered at 3 degrees C for 120 d.