CONSUMPTION OF SUGAR-BEET LEAF AREA BY THE TORTOISE BEETLE, Cassida vittata VILL

Abstract

Feeding experiment was carried out on Cassida vittata Vill. under out door conditions. Sugar-beet leaf area consumption of larval and adult stages was estimated. The mean sugar-beet leaf area consumption was 170.5 mm 2 per larva during 17 days. The 4th and 5 th instars consumed 84.4% of the total leaf area consumption. The newly emerged adult consumed 754.3 mm 2 of sugar-beet foliage during 28 days, while reactivated adult consumed 2369 mm 2 for a period of 80 days, the mean sugar-beet leaf area consumed by one adult over mature stage (before and after diapause) was 3123.3 mm 2 , represents Ca. 94.8% of the total consumption. The mean consumed by a single individual of Cassida vittata throughout its life span (larva and adult) was 3293.8 mm 2 for a period of 125 days. The adult female laid an average of 190.7 + 7.44 eggs/female and oviposition period averaged 37.67 + 3.06 days.