Abstract
The mortality during the nymphal stage of Palomena angulosa MOTSCHULSKY did not vary significantly among groups exposed to decreasing and stationary photoperiods, ranging from 16 to 28%. Irrespective of whether decreasing or stationary, shorter photophase conditions promoted nymphal growth. A significant correlation was found between the nymphal period and photophase. The nymphal period (y days) in x hr or photophase per day could be represented by the equatio, y=10.5x-101.8. Whether decreasing or stationary, shorter photophases promoted daily weight gain. This compensated, to a certain extent, for the limited growth period under short-day conditions.
