Reproductive polyphenism, which allows one genotype to produce sexual and asexual morphs, is an extreme case of phenotypic plasticity and is commonly observed in aphids. Aphids are typical species that switch these reproductive modes, and the pathway orientation is triggered by the environmental conditions (mainly photoperiod and temperature). The typical annual life of aphids includes a succession of parthenogenetic generations during the spring and summer and a single sexual generation in autumn. In this review, we describe how the environmental cues orientate the reproductive mode of aphids from photoperiodic perception to endocrine regulation, and how juvenile hormones may act on the target cells (oocytes) to initiate the gametogenesis and embryogenesis in sexual and asexual reproduction. We also discuss the paradox of sex, especially the advantages of sexual reproduction in aphids. With the recent development of genomic resources in aphids, many potential genes involved in the reproductive polyphenism will enter the public's awareness. In particular, we describe a novel RNAi method in aphids, which may provide a molecular technique for determining the developmental fate and multiple reproductive strategies.

生殖多态性允许一种基因型产生有性和无性形态，是表型可塑性的极端情况，通常在蚜虫中观察到。蚜虫是切换这些繁殖方式的典型物种，途径的方向是由环境条件（主要是光周期和温度）触发的。蚜虫的典型年度生活包括在春季和夏季的一系列孤雌生殖世代和秋季的单性世代。在这篇综述中，我们描述了环境线索如何将蚜虫的生殖方式从光周期感知转向内分泌调节，以及少年激素如何作用于靶细胞（卵母细胞）以启动有性生殖和无性生殖的配子发生和胚胎发生。我们还讨论了性的悖论，尤其是蚜虫有性生殖的优势。随着近来蚜虫基因组资源的发展，许多涉及生殖多态性的潜在基因将进入公众的视野。特别是，我们描述了一种在蚜虫中的新型RNAi方法，该方法可为确定发育命运和多种繁殖策略提供分子技术。