Performance ofAphis Fabae on Chocolate Spot Disease-Infected Faba Bean Plants

The effect of chocolate spot disease (incited byBotrytis fabae) on the host plant quality of two cultivars of faba beans (Vicia faba) for the black bean aphid (Aphis fabae), was investigated under greenhouse conditions. Faba bean cultivar Bolero is resistant to the aphid, whereas cv. Diana is susceptible. On healthy leaves of cv. Bolero, aphids completed their development one day later than the aphids reared on infected leaves of this cultivar and those which matured on healthy or infected leaves of cv. Diana. Mean weight of apterous virginoparae, mean relative growth rate, and intrinsic rate of natural increase were enhanced if the aphids were reared on infected leaves of either cultivar. Mean total progeny per female increased only on infected leaves of cv. Bolero, but not on cv. Diana.