EFFECT OF CARBOHYDRATE ON THE FECUNDITY OF THE SPOTTED TENTIFORM LEAFMINER, PHYLLONORYCTER BLANCARDELLA (LEPIDOPTERA: GRACILLARIIDAE)

Abstract

The spotted tentiform leafminer, Phyllonorycter blancardella (Fabr.), is an important pest of apple in Ontario (Pree et al. 1980), Michigan (Dutcher and Howitt 1978), and New York (Weires et al. 1980). In Ontario, the leafminer has three generations per year (Johnson et al. 1976) and overwinters as a diapausing pupa in the leaf litter (Trimble 1983). Considerable variation exists in the reported fecundity of P. blancardella. For example, Bagdavaze (1963) found that females laid from 11 to 33 eggs whereas Baumgartner et al. (1981) reported an average of 102 eggs per female. One possible source of this variation could be the availability of carbohydrate to ovipositing females as was suggested by the results of Pottinger and LeRoux (1971) who studied a Quebec population of P. blancardella. The objectives of the present study were to determine the effects of carbohydrate on female longevity and fecundity (number of eggs laid) and egg viability.