Survival of Immature Citrus Blackfly, 1Aleurocanthus woglumi , and Its Parasite, Amitus hesperidum , 2 on Excised Leaves

Abstract

One known means of dispersal of the citrus blackfly, Aleurocanthus woglumi Ashby, and its parasite, Amitus hesperidum Silv., is by survival of immature stages on excised leaves. Under screenhouse conditions, 1st, 2nd, and 3rd instars of the citrus blackfly on excised leaves all died before completing development. No significant difference was found in the adult emergence from 4th instars on different host plants tested, or with fruit still attached to sweet orange leaves, the average emergence being only one percent. In contrast, 4th instars stored at high humidity had a significantly greater adult emergence (19%). Of the various cool storage conditions tested, A. hesperidum on excised leaves could be safely stored at 10°C for at least 4 weeks, resulting in delayed adult emergence and no significant loss of viability.