三种寄主植物对扶桑绵粉蚧发育和繁殖的影响

［目的］ 研究棉花、番茄和茄子3种寄主植物对扶桑绵粉蚧生长发育和繁殖的影响。［方法］ 在恒温27 ℃下观察扶桑绵粉蚧的个体发育及种群发展情况，记录并分析各虫态的发育历期、存活率及实验种群生命表参数。［结果］ 扶桑绵粉蚧在3种寄主植物上的平均存活率为棉花﹥茄子﹥番茄，存活曲线差异明显，但均以l龄和2龄若虫的死亡率最高。若虫的发育历期除1龄外无显著差异，棉花上蛹期显著长于其他两者，雌性成虫存活历期为棉花﹥番茄、茄子，雄性为棉花、茄子﹥番茄。交配过的扶桑绵粉蚧雌成虫多于夜间产卵，但棉花上部分扶桑绵粉蚧可于白昼产卵；其在3种寄主植物上的产卵能力为棉花﹥茄子﹥番茄。3种寄主上扶桑绵粉蚧种群的内禀增长率（rm）和周限增长率（λ）相近，但净增殖率（R0）及种群增长趋势指数（I）差异较大，均为棉花﹥茄子﹥番茄，分别为142.10、88.91、43.56和156.67、87.95、32.74。［结论］ 扶桑绵粉蚧繁殖力及种群发展能力极强，从而使其具备较强的环境适应性，是其极易大规模发生的主要原因。

Effects of three host plants on the development and reproduction of Phenacoccus solenopsis

［Objective］To study the effect of three host plants, cotton (Gossypium hirsutum Linn.), tomato (Lycopersicon esculentum Mill.) and eggplant (Solanum melongena Linn.), on the development and reproduction of the mealybug (Phenacoccus solenopsis Tinsley).［Method］ Under 27 ℃, developmental duration, survival rate and parameters of life table of mealybugs were recorded and analyzed.［Result］P. solenopsis on different host plants was in the order from high to low survival rates as followed: cotton, eggplant and tomato. Though the survival curves on three host plants were significantly different, the highest mortality during the lifespan all happened in the 1st and/or 2nd instar larval stages. Larval developmental duration on three hosts had no significant differences, except that the first instar larvae and pupal phase on cotton were significantly longer than others, and female adult survival duration on cotton was longer than that on tomato and eggplant, and males on tomato had shorter survival duration than on other plants. P. solenopsis oviposited at nights, but some on cotton could oviposited during days. The mated females was in the order from strong to weak reproductive ability as follows: cotton, eggplant and tomato. Intrinsic rate of increase and finite rate of increase on three hosts had no significant differences, but net reproductive rate or index of population trend on cotton was the highest, while those on tomato were the lowest. ［Conclusion］ The strong ability of reproduction and population development resulted in high environmental adaptability, which was the most important reason for quick spreading of this mealybug.