| By means of biology and ecology, The life history divergence was studied in Carposina sasakii, on the basis of the research concerning its seasonal history, hosts, parasites, photoperiod reaction of diapause as well as the ingredient of food nutrition.The main research items and the results are as follows:1. Developmental zero and effective accumulated temperature of the period of over-wintered larvae emerging from ground and adult emergence of C. sasakii on apple, hawthorn, wild date, apricot and date are measured under constant temperature. The results show that developmental zero do not vary greatly, with the lowest temperature on apple population as 6.31℃ and the highest on apricot as 6.98℃. The effective accumulated temperature are 221.91 day-degrees on apple, 217.58 day-degrees on hawthorn, 216.75 day-degrees on wild date, 200.60 day-degrees on apricot and 216.11 day-degrees on date, respectively.2. Developmental zero and effective accumulated temperature of the first generation eggs are measured under constant temperature on different hosts. The results show that developmental zero between 7.22℃ and 7.78℃ has no distinctive difference, and effective accumulated temperature has no clear difference between 101.72 day-degrees and 103.95 day-degrees.3. The responses of grown larvae diapause to photoperiods were studied on apple, hawthorn, wild date, apricot and date. The results show that under the constant temperature of 25°C, incidence of diapause is almost 100% on apricot except 14h30min, while the critical photoperiod are 14h25mim on apple, 14h28mim on hawthorn, 14h40mim on wild date, 14h25mim on date. This means that larva diapause differs greatly on various plants, and plays a key role in the life history divergence.4. The parasites differ greatly on from different plants, indicating that has already been undergoing speciation. Developmental zero and effective accumulated temperature of the first...
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