| The differences in life-table demographic parameters, asexual and sexual reproduction, and developing rate and fecundity of rotifer Brachionus calyciflorus between/among different geographic regions and seasons were investigated, and the main results were presented as the following:1. The life-table demographic parameters of B. calyciflorus collected respectively from Wuhu and Guangzhou in spring, summer, autumn and winter, and cultured at different temperatures were investigated by means of life-table demographic approach. The results showed that the responses of life-table demographic parameters to the increasing temperature depended on geographic regions and seasons from and in which the rotifers were collected. Three-way analysis performed for all the life-table demographic parameters of the rotifers collected in spring, summer and autumn showed that season affected significantly all the life-table demographic parameters (P<0.01); geographic population, temperature and their interaction affected life expectancy at hatching, generation time and proportion of sexual offspring (P<0.05). Two-way analysis for all the life-table demographic parameters of the rotifers collected in winter showed that temperature affected significantly all the life-table demographic parameters except the proportion of sexual offspring, geographic population affected generation time, intrinsic rate of population increase and proportion of sexual offspring, the interaction of geographic population×temperature affected all the life-table demographic parameters.2. Differences in asexual and sexual reproductions of B. calyciflorus collected respectively from Wuhu and Guangzhou in spring, summer, autumn and winter, and cultured at different temperatures were investigated, with 3.0×106cells ml-1 of S. obliquus as the rotifers'food. The results showed that the responses in population growth rate, mictic rate, fertilization rate of mictic females and resting egg production to the increasing temperature depended on geographic regions and seasons from and in which the rotifers were collected. Three-way analysis performed for all the reproductive parameters of the rotifers collected in spring, summer and autumn showed that temperature affected significantly all the reproductive parameters except the mictic rate, and they increased with the increasing temperature. Season affected significantly population growth rate and mictic rate. The population growth rate of the rotifers collected in autumn was higher than that in summer, but both of them were similar to that in spring. The mictic rates of the rotifers collected in summer and autumn were similar, but higher than that in spring. Geographic population affected significantly all the reproductive parameters except the population growth rate, and those of the rotifers collected from Wuhu were higher than those from Guangzhou. Two-way analysis for all the reproductive parameters of the rotifers collected in winter showed that temperature affected significantly all the reproductive parameters except the fertilization rate of mictic females, and they increased with the increasing temperature. Geographic population affected all the reproductive parameters except the population growth rate, and those of the rotifers collected from Wuhu were higher than those from Guangzhou.3. The durations of principal developing stages and the number of eggs produced in life of the rotifers collected respectively from Wuhu and Guangzhou in spring and summer, and cultured at 18℃, 23℃and 28℃and with 3.0×106cells ml-1 of S. obliquus were compared by means of individual culture method. The results showed that the responses in durations of pre-reproductive period, reproductive period and post-reproductive period, mean lifespan and number of eggs produced by females in her life to the increasing temperature depended on geographic regions and seasons from and in which the rotifers were collected. Three-way analysis performed for all the parameters showed that temperature affected significantly all the durations of developing stages, and they decreased with the increasing temperature. Geographic population affected significantly durations of pre-reproductive period and reproductive period, and those of the rotifers collected from Guangzhou were longer than those from Wuhu. The interaction of temperature×geographic population affected the duration of pre-reproductive period, and that of season×geographic population affected the duration of reproductive period. The spatial differentiation of the durations of principal developing stages of the rotifers was more obvious than the temporal (seasonal) differentiation.
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