饲养密度对大蜡螟实验种群生命表参数的影响

大蜡螟是蜜蜂蜂群的主要害虫，也是重要的模式昆虫，其饲养条件的优化对获得大量试虫进而推动昆虫免疫及昆虫病理学研究有着重要作用。密度是影响昆虫生长发育重要的生物因子之一，饲养密度对人工种群的个体发育与存活有重要影响。设置20、30、40、60头·300 cm-3 4个饲养密度，采用年龄-龄期两性生命表分析大蜡螟实验种群的密度效应，比较不同饲养密度对大蜡螟发育、繁殖及种群参数的影响，估计种群动态，进而探究大蜡螟实验室饲养的适宜密度。结果表明，饲养密度最小（20头·300 cm-3）的种群，内禀增长率r(0.136 3±0.003 7 d-1)、周限增长率λ(1.146 0±0.004 2 d-1)均为最高（P<0.05），净增殖率R0(724.50±11209粒卵）最大。饲养密度增加后，r和λ显著降低（P<0.05），净增殖率下降。特定年龄-龄期存活率sxj、种群特定年龄繁殖力mx、和种群年龄净增殖率lxmx在低密度（20头·300 cm-3）种群中保持较高水平，随着饲养密度增加，参数值明显变小。4个密度饲养的大蜡螟种群，蛹期虫体收获率均在99%以上。较高密度饲养条件下，给予充足食物，在相同空间内可获得较多的大蜡螟个体，但低密度饲养有助于缩短种群发育历期，且饲养的个体和种群具有较高繁殖潜力，适于实验室种群维持，因此要根据研究目的合理设置饲养密度。研究结果为进一步优化大蜡螟实验室种群饲养，推动模式昆虫研究提供了理论依据。

Effect of Rearing Density on Life Table Parameters of the Laboratory Population of Galleria mellonella L.

The Galleria mellonella L. is a serious pest of honey bee colony, and also is one of the most important research model insect. The optimization of rearing conditions is very important for maintaining mass-rearing system and promoting research on insect immunity and insect pathology. Density is one of the most important biological factors in the rearing process, so it has an important effect on the growth and development of laboratory insect population or individual. Four densities of G. mellonella population were set at 20, 30, 40, 60 individuals·300 cm-3 in the present paper to explore suitable rearing density for laboratory population. The population and individual parameters were analyzed by age-stage two-sex life table to evaluate the effect caused by the rearing density. The results showed that the intrinsic rate of increase (r=0.136 3±0.003 7 d-1) and the finite rate of increase (λ=1.146 0±0.004 2 d-1) were the highest at the lowest rearing density (20 individuals·300 cm-3) among 4 treatments (P<0.05), and the net reproductive rate (R0=724.50±112.09 eggs) was the highest as well. The r and λ decreased significantly (P<0.05) when the rearing density increased, and R0 decreased as well. The age-stage-specific survival rate (sxj), cohort age-specific fecundity (mx) and age-specific maternity (lxmx) reached high level in the population at 20 individuals·300 cm-3, and the values decreased obviously when the rearing density increased. The pupal harvest rate of population was above 99% in all treatments. Given enough food, more individuals could be obtained in the same space at higher rearing density, but the developmental period of the population was significantly shorter at the lower rearing density. It was suitable for maintaining the population in the laboratory to rear G. mellonella at the lower rearing density, with higher reproductive potential. Therefore, the rearing density should be set reasonably according to the research purpose. The results provided a theoretical basis for further optimizing the laboratory population rearing of G. mellonella and promoting the study as a model insect.