【目的】研究在实验室条件下,咖啡豆象Araecerus fasciculatus生命活动对不同相对湿度环境的适生性,并通过组建实验种群生命表,明确相对湿度对其种群增长的影响。【方法】实验设定30%、45%、60%、75%、90%5个相对湿度梯度,观察比较咖啡豆象卵、幼虫、蛹历期及其存活率、成虫寿命、单雌产卵量。【结果】在30%~90%范围内,随相对湿度的增加咖啡豆象幼虫发育历期缩短,卵至蛹期存活率、成虫寿命及繁殖力提高。相对湿度为90%时,卵、幼虫、蛹存活率最高且发育历期最短,成虫寿命最长,单雌产卵量最高。各湿度生命表参数内禀增长率(r_m)在0.197~0.319之间,相对湿度75%时最高;净增殖率(R_0)在9.653~73.493之间,相对湿度90%时最高。此外,内禀增长率(r_m)、净增殖率(R_0)与相对湿度关系符合Logistic模型,分别为y=0.32/1+exp(1.71-0.07x)(R~2=0.90442,P=0.00201)和y=78.13/1+exp(5.03-0.09x)(R2=0.98931,P=0.00213)。【结论】研究表明相对湿度是影响咖啡豆象生长发育、繁殖力、种群增长的重要因素,有助于进一步了解气象环境条件对咖啡豆象的影响,同时为其种群增长数学模型的拟合提供参考。
[Objectives] To investigate the effects of relative humidity on the development, fecundity, and growth, of a laboratory population of Araecerus fascilatus. [Methods] The development and subsequent fecundity of larvae and pupae of A. fascilatus reared at 30%, 45%, 60%, 75%, 90% r.h. were monitored and compared. [Results] Higher relative humidity was associated with a shorter larval stage, increased survival and higher adult female fecundity. The shortest developmental duration, and highest survival, adult longevity and fecundity, were observed in larvae and pupae that were kept at 90%RH. The intrinsic rate of increase(r_m) ranged from 0.209 to 0.330 and was highest at 75%r.h., The net reproductive rate(R_0) ranged from 9.653~73.493 and was highest at 90% RH. The relationships between rm, Ro and relative humidity were good fits to the logistic models y=0.32/1+exp(1.71-0.07x)(R~2=0.90442, P=0.00201) and y=78.13/1+exp(5.03-0.09x)(R~2=0.98931, P=0.00213), respectively. [Conclusion] The results suggest that relative humidity is a factor influencing the reproduction and phenology of Araecerus fascilatus, and that incorporating this in population models may improve their accuracy and predictive power.