温度和食物对褶皱臂尾轮虫种群增长及繁殖的影响

本试验设3个温度（20、25和30℃）和3个食物浓度（1×106、10×106和20×106 cells/mL），研究不同温度和不同食物浓度对褶皱臂尾轮虫种群增长及繁殖的影响。试验期为10 d。结果表明，最大种群密度均随温度和食物浓度的升高而先增加后减少。温度为25℃食物浓度为10×106 cells/mL时，最大种群密度为74.39±1.81 ind/mL，与其他组比差异显著（P〈0.05）。随温度升高，轮虫的最大种群密度高峰值出现的时间也呈现逐渐前移的趋势，最大种群增长率则随温度和食物浓度的增加而升高。温度30℃食物20×106 cells/mL时，最大种群增长率为0.70±0.013，与其他组比差异显著（P〈0.05）。食物浓度对轮虫的怀卵率有显著影响，在同一温度下最大怀卵率随食物浓度的升高而增大，食物为20×106 cells/mL的最大怀卵率为56.43±1.07%，与其他浓度组比差异显著（P〈0.05）。在本试验条件下，温度和食物对褶皱臂尾轮虫的种群增长及繁殖均有显著影响。温度25℃食物浓度10×106 cells/mL为培养条件的最优组合。

Effects of temperature and food on population growth and reproduction of rotifer,Brachionus plicatilis

Effects of temperature and food concentration on population growth and reproduction of rotifer, Brachionus plicatilis were studied in growth three temperatures （20℃,25℃ and 30℃） and different food concentrations （1 ＆#215; 106cells/mL,10 ＆#215; 106cells/mL and 20 ＆#215; 106cells/mL）. The culture was lasted for 10d. The results showed that there were very significant in the effects of tempera-ture and food concentration on the population density, population growth rate and egg ratio. The maximum population density decreased after the first increase with temperature and food concentra-tion increase. When the food concentration was 10＆#215;106cells/mL at 25℃, the maximum population den-sity was 74.39 ＆#177; 1.81ind/mL, which was significantly higher than that in the other groups（P＆lt;0.05）. With the increase of temperature, the time of maximum peak rotifer population density also showed a gradual emergence of forward trends, the largest population growth rate increased with the in-crease of temperature and food concentration. When the food concentration was 20 ＆#215; 106cells/mL at 30℃, the largest population growth rate was 0.70＆#177;0.013 which significantly higher than the other groups（P＆lt;0.05）. At the same temperature, the maximum egg ratio increased with the increase of con-centration in food. When the food concentration was 20 ＆#215; 106cells/mL, the maximum egg ratio was 56.43＆#177;1.07%, which was significantly higher than in the other groups（P＆lt;0.05）. In conclusion, tem-perature and food concentration had significantly effects on the population growth and the repro-duction of rotifer, Brachionus plicatilis. It is suggested that the optimum food concentration was 10＆#215;106cells/mL and the temperature was at 25℃.