On the Natural Enemy of the Tea Red Spider Mite, Tetranychus kanzawai KISHIDA

Abstract

In this paper, the results of survey on the natural enemies of the tea red spider mite, Tetranychus kanzawai KISHIDA, in the tea cultivating area, of Japan, were described.According to the results of field survey in 1960-'61, 6 species were found to be the natural enemies of the mite ; they are Scolo-thrips sexmaculatus PERGANDE, Arthrocnodax sp., Planipennia Gn. sp., Coccinellidae Gn. sp., Agistemus fleshneri SUMMERS, and Ambly-sieus largoensis (MUMA). Three species of natural enemies of mite, Scolothrips sexma-culatus PERGANDE, Arthrocnodax occidental is FELT, and Oligota oviformis CASEY have been, well known in the tea garden of Shizuokaken. However, Oligota oviformis was not found in this survey.The population density of Scolothrips sex-maculatus, Arthrocnodax sp., Agistemus fleshneri, and Amblysieus largoensis was higher than that of the other three species.For each natural enemy of tea red spider mite, a high population density was observed in the following periods : Scolothrips sexmaculatus, from April to September ; Arthrocnodax sp., May to July ; Planipennia Gn. sp., April to June ; Coccinellidae Gn. sp., April to November ; Agistemus fleshneri, May to July ; and Amblysieus largoensis, June to October.Scolothrips sexmaculatus, Arthrocnodax sp., Agistemus fleshneri, and Amblysieus largoensis were spread in all tea cultivating areas in Japan, but Planipennia Gn. sp., Coccinellidae Gn. sp., and Oligota oviformis were restricted in some districts.