杂种优势作为自然界的普遍现象,其产生机理一直是人类研究的热点。在此基础上,关于杂种优势的原因产生了众多理论假说,诸如显性假说、上位效应、基因表达调控网络等。多年来,众多科研工作者试图从生理生化水平和分子水平求解杂种优势产生的机理,发现杂种优势植株光合能力强,组织相对发达,对外界环境变化的适应和缓冲能力较强;杂种优势在相对弱光、低温、低CO2浓度条件下往往表现得更为明显;此外,遗传距离、基因表达差异、DNA甲基化等都与杂种优势关系密切。文中对农业和林业上的研究成果进行了综述和思考,并对这一领域今后的研究方向进行了探讨。 Heterosis, as a common phenomenon in nature, has always been the focus of human research. On this basis, many theoretical hypotheses have been made on the causes of heterosis, such as dominant hypothesis, epistatic effect, gene expression regulation network and so on. Over the years, many researchers tried to find out the mechanism of heterosis arising from physiological and biochemical level and molecular level. It was found that heterosis plants had strong photosynthetic ability, relatively well-organized tissues and strong adaptation and buffering capacity to external environmental changes. Low light, low temperature, low CO2 concentrations tend to be more obvious; In addition, genetic distance, gene expression differences, DNA methylation are closely related with the heterosis. In this paper, the research results on agriculture and forestry are reviewed and considered, and the future research directions in this field are discussed.