Black Parlatoria, Parlatoria Zizyphus (Lucas)

Abstract

The black Parlatoria, Parlatoria zyziphus (Lucas) was the most difficult to control by insecticides owing to its scale was so flat and firmly stick on the leaf, twig or fruit peel lack of effective parasitic wasps or other groups of natural enemies. In consequence of its infestation was severe over other scale insects infested at present. Therefore the writers reviewed and tried insecticlede control of this species, the results may be summaried in the following. Species and its generic characters had been described and differences among other species belonging to the same genus were presented in the key. The hosts seemed to limit various varieties of Citrus only on this islands. It took 7 generations a year, morphology of each stage was briefly described. Durations of egg, 1st, 2nd, 3rd stadium, oviposition period and one generation were 2-4, 6-13, 13-30, 11-24, 7-18, 42-93 days respectively. There were 4 species of parasitic wasps namely Aphytis chrysomphali (Mercet) A. proclia (Walker), Aspidiotiphagus citrinus Craw and A. lounsburyi (Berlese and Paoli) recorded but the percentage of parasitism was very low and not over 2%. The morphology of each parasitic wasps was also briefly described. 1, 1.25, 1.5% of five sauces of summer oil, 2, 2.5, 3% of CPC summer oil, 0.015, 0.0375, 0.05, 0.10% dimethoate, 0.05, 0.1% malathion alone, 0.05% malathion plus 1% CPC summer oil, solvent less and solvent parathion 0.025, 0:05, 0.1%, 0.05, 0.1% lebaycid, folithion, dimecron, nuvan (DDVP) and gusathion, diazinon, nuvan (0.025% each extra) were teated in the field, Among them, only 0.05% parathion, dimethoate and 0.05% malathion plus 1% summer oil or 3% summer oil alone were good and the mortality of the adult was over 95% and could be accepted for recommendation to control this species in Taiwan except parathion in present condition.