摘  要  【目的】 明确雄螨数量对二斑叶螨Tetranychus urticae雌成螨繁殖潜力的影响，研究配对性比在种群变化中的关键作用，为害螨发生的预测预报提供科学依据。【方法】 采用离体叶片饲养法，研究了不同性比结构（♀︰♂=3︰0、3︰1、3︰2、3︰3和3︰4）对二斑叶螨单雌产卵量、产卵历期、雌成螨寿命以及子代孵化率、羽化率和性比的影响。【结果】 配对雄螨数量对二斑叶螨雌成螨的生殖力、雌成螨寿命及子代适合度有显著影响：二斑叶螨营两性生殖时，其产卵量均低于孤雌生殖（97.64粒/雌），雌成螨的产卵历期随着配对雄螨数量的增加逐渐缩短；孤雌生殖的二斑叶螨雌成螨平均寿命显著长于有性生殖（P<0.05），且随雄螨密度的增大而降低；孤雌生殖和两性生殖的二斑叶螨子代（卵）孵化率与子代（若螨）羽化率无显著差异（P>0.05），均达90%以上；二斑叶螨孤雌生殖时子代全为雄性，两性生殖时以产雌为主，性比接近3︰1。【结论】 孤雌生殖的二斑叶螨繁殖力高于两性生殖；不同性配比对二斑叶螨后代适合度无影响；二斑叶螨种群有性比自调节能力，孤雌生殖的后代都是雄性，随着配对雄螨数量的增加，有性生殖率增加，后代以雌螨为主。

Abstract  [Aim]  To investigate the effects of paired males on the reproduction potential of adult female Tetranychus urticae. This study aims to determine the key role of sex ratio in population dynamics to establish a scientific foundation for predicting mite population trends. [Methods]  A single head feeding technique using the isolated leaf feeding method was employed to investigate the effects of different sex ratios (♀︰♂=3︰0, 3︰1, 3︰2, 3︰3, 3︰4) of T. urticae on female oviposition, oviposition period and adult longevity, as well as offspring hatch rate, eclosion rate and sex ratio. [Results]  Reproductive fitness, female adult longevity and offspring fitness were significantly affected by the number of paired males. Mated female T. urticae laid significantly fewer eggs per female compared to unmated females (97.64/female). The oviposition period for mated females gradually decreased with an increasing number of males. Adult longevity was significantly longer in unmated females compared to mated females（P<0.05）. Additionally, adult longevity decreased as the number of males increased. There was no significant difference between mated and unmated females in egg hatch rate or nymph eclosion rate (P>0.05), both of which were above 90%. The offspring resulting from parthenogenesis were all male, while offspring from sexual reproduction were predominantly female, with a sex ratio close to 3︰1. [Conclusion]  The fecundity of parthenogenic females was higher than amphigenetic females. Different maternal sex ratios had no effect on offspring fitness of T. urticae. T. urticae population has self-regulation ability of sex ratio, the offspring resulting from parthenogenesis were all male. As the number of male mites increased and they paired with females, the rate of sexual reproduction increased, resulting in predominantly female offspring.