VARIABILITY OF DIAPAUSE IN POPULATIONS OF HELIOTHIS-ARMIGERA HB

The incidence of diapause in some populations of Heliothis armigera co llected between latitudes 25-degrees-S to 44-degrees-N was examined. D iapause occurred in all populations reared in short photoperiod situat ion (LD < 12:12). The percentage of pupae in diapause was variable. Th e effect of family and the dates of collecting samples from adjacent m arroccan populations in diapause and its intensity was measured. Signi ficant heterogeneity in diapause induction and development was found b etween and in populations and families. However, there is little evide nce of any geographicA pattern to this variation.