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【目的】研究阐明不同光周期条件下棉花粉蚧Phenacoccus solenopsis Tinsley实验种群的发育历期、繁殖和数量动态规律,为制定该虫防治对策、研究治理措施等提供科学依据。【方法】以扶桑为寄主,在温度27±1℃、相对湿度70%±5%、光照强度4 000 lx及不同光周期(8L∶16D,10L∶14D,12L∶12D,14L∶10D和16L∶8D)条件下,观察了棉花粉蚧实验种群的生长发育特性和繁殖能力,组建了实验种群生命表。【结果】不同光周期处理下棉花粉蚧1龄若虫和3龄若虫的发育历期及雌成虫产仔量均发生了变化,但不同龄期若虫存活率之间差异不大。随着光照时间增加,棉花粉蚧1龄若虫、3龄若虫发育速率加快,8 h光照时发育历期分别为5.43 d和6.35 d,而16 h光照时发育历期分别缩短至4.16 d和4.75 d;整个若虫发育历期也由8 h光照时的15.54 d缩短至16 h光照时的12.74 d,世代历期由27.75 d缩短至23.45 d。长光照时雌虫更早进入产仔期,也有利于雌虫繁殖后代,16 h光照时进入产仔期是18日龄,8和10 h光照时均推迟至22日龄;16 h光照时单雌产仔量为417.06头,明显高于12,10和8 h光照时的353.59,347.61和336.00头。长光照条件下实验种群趋势指数(I)明显较大,增长潜能更大,16,10和8 h光照时种群趋势指数分别为175.37,133.94和141.99。该虫生命表参数表明,随着光照时间加长净增值率(R0)呈逐渐增大趋势,8,10,12,14和16 h光照时分别为88.57,86.85,100.77,124.16和126.86;内禀增长率、周限增长率表现类似的规律,8~16 h光照时内禀增长率(rm)为0.1616~0.2066,周限增长率(λ)为1.1754~1.2294;而种群倍增时间(t)则随着光照时加长而缩短,8~16 h光照时为4.29~3.36 d。【结论】长光照有利于棉花粉蚧生长发育和繁殖,世代历期缩短,种群增长潜能变强。
【Objective】 The objective of this study is to elucidate the developmental history, population and dynamics of Phenacoccus solenopsis Tinsley population under different photoperiod conditions and to provide a scientific basis for the development of this pest control strategy and research and treatment measures. 【Method】 The experiment was carried out under the conditions of temperature 27 ± 1 ℃, relative humidity 70% ± 5%, light intensity 4000 lx and different photoperiods (8L: 16D, 10L: 14D, 12L: 12D, 14L: 10D and 16L : 8D), the growth and development characteristics and reproductive capacity of experimental population of cotton mealybugs were observed, and the life table of experimental population was established. 【Result】 The results showed that the developmental stages and the female litter size of 1st instar nymphs and 3rd instar nymphs of cottonseed mealybugs changed under different photoperiod treatments, but there was no significant difference in the survival rates of nymphs at different instars. With the increase of light time, the developmental rates of 1st instar nymphs and 3rd instar nymphs in cottonseed mealybugs accelerated at 8 h and 5.43 d and 6.35 d, respectively, while their developmental duration at 16 h light was shortened to 4.16 d and 4.75 d d. The whole nymph’s developmental period was also shortened from 15.54 days at 8 hours of illumination to 12.74 days at 16 hours of illumination, and the generational period was shortened from 27.75 days to 23.45 days. In the long light, the females earlier entered the littermate stage, which also benefited the females to reproduce. The litter size of the females was 18 days at 16 hours light and 22 days at 8 and 10 hours. The number of single females was 417.06, which was significantly higher than that of 353.59, 347.61 and 336.00 at 12, 10 and 8 hours. Under long light conditions, the trend index (I) of the experimental population was significantly larger and its growth potential was greater. The population trend indices at 16, 10 and 8 h illumination were 175.37, 133.94 and 141.99, respectively. The worm life table parameters showed that the net increment rate (R0) tended to increase with the increase of light time, and reached 88.57, 86.85, 100.77, 124.16 and 126.86 at 8, 10, 12, 14, (Rm) was 0.1616 ~ 0.2066 and the growth rate of the cycle (λ) was 1.1754 ~ 1.2294 at 8-16 h, while the population doubling time (t) was With the lengthening and shortening of illumination, it was 4.29 ~ 3.36 d in 8 ~ 16 h light. 【Conclusion】 The long light illumination is beneficial to the growth and reproduction of cottonseed mealybugs, shortening the generational duration and strengthening the potential of population growth.