Abstract: The mechanism of plant sex expression adaptation to environmental factors is an important topic in evolutionary biology and ecology research. Plants show complex and diverse adaptations to environmental factors, and are affected by their own gene regulation and hormone synthesis. Therefore, sex expression patterns of plants vary with the changes of environmental factors. Understanding the sex expression strategies of plants has important theoretical significance for indepth understanding of the mechanisms of plant sexual diversity and variability. We reviewed the effects of four abiotic environmental factors, including mineral nutrients, light, water, and temperature, on plant sex expression and their underlying mechanisms. Mineral nutrition and temperature mainly regulate plant sex expression by affecting hormone synthesis and some metabolic pathways and metabolites in plants. In addition to the aforementioned effects, light and water also regulate plant sex by regulating the differential expression of plant sexrelated genes. A few plant species have been studied at the molecular level, and some of studies are still in the stage of comparative research on morphological structure and functional traits. Moreover, most studies are conducted with short-term experiments under artificially controlled environmental conditions, which are insufficient to reveal the sex expression characteristics of perennial plants that adapt to changing environments. Future researches should be conducted at long-term scale, and investigate the reproductive status of more plant species across multiple years. Moreover, we should strengthen molecular-level studies on the effects of different environmental factors on plant sex expression in natural habitats to reveal the environmental determination of plant sex expression.

Key words: environmental factor, sex expression, mineral nutrition, moisture, temperature