The bionomics of Anastatus sp. and its utilization for the control of lichee stink bug. Tessaratoma papillosa Drury.

Abstract

Liberation of the indigenous egg-parasite, Anastatus sp. to control the lichee stink bug, Tessaratoma papillosa was proved to be highly effective through the field experiments during 1966 and 1967 in the orchards of People's Communes and this control method has been widely adopted in practice in the lichee-producing districts of the Pearl River Delta of Kwangtung Province.Anastatus sp. overwinters in prepupal stage within its host egg from mid November and the adult emerges in mid or late March of the following year. This parasite completes its life cycle at 26-28℃ between 18 and 21 days, in which the egg stage lasts 2 days, the larval stage 5-6 days, the prepupal stage 5-6 days and the pupal stage 6-7 days.The values for the velocity of development at 24-34℃ computed from the data of experiments were fitted to a temperature-velocity curve with the formula 1/y= 8.659/1+e6.449-0.2440.Humidity does not effect the velocity of development significantly, but the adults emerged from the immature stage exposed to higher humidity would have a shorter life span.The longevity of male adults fed with honey is 5-10 days while that of the female is 30-40 days. The total number of offsprings produced by one female is 228.2 in average with daily averages ranging from 5.7 to 11.3. The oviposition is concentrated within 25 days after emerging. A condition of 25-30℃ and 70-80% E. H. is favorable for oviposition of Anastatus sp.The fresh eggs of Eri-silkworm, Samia cynthia ricini are favorable host eggs for mass propagation of this parasite and the host eggs preserved in frozen condition even up to one year are still suitable for this purpose.During sexual reproduction the adults exposed to the dim light or higher temperature would produce more male individuals in the progeny. Parasitized host eggs of smaller size and the host eggs to be parasitized at the later stage of embryonic development would emerge more male individuals.The female parasites is parthenogenetic arrhenotokous.For the accumulation of large quantity of the parasites during mass propagation the larvae of first or second instar are kept in cold storage of 10-12℃. The parasites are not affected by low temperature in cold storage even up to six months and they develop quite normally when return to the suitable higher temperature.A wooden box with 416 criss-cross cells for mass propagation of Anastatus sp. was deviced.