Effects of light on the germination of dominate plant seeds in an abandoned cropland in northern Shaanxi

During seed germination, the light sensitivity of seeds can guarantee germination and emergence of seedlings under appropriate conditions. Therefore, the presence or absence of light can affect seed germination of certain species. In this study, 10 dominate plant seeds from an abandoned cropland in northern Shaanxi were chosen as research material. Seed germination characteristics were observed under both full-light and full-darkness conditions. The results showed that most of the 10 dominate plants germinated quickly. Under light conditions, the germination of seeds of 7 species reached T₅₀ (time at which the number of germinated seeds reaches 50% of the total number of germinated seeds) within 4 days (d), and the minimum T₅₀ was 9 d. Among all the experimental species, there were 7 species that achieved T₉₀ in a shorter time under light conditions. Additionally, the seed germination index of different species under light conditions was significantly different. The seeds of species, including Dracocephalum moldavica, Artemisia sacrorum, Leonurus artemisia, Potentilla tanacetifolia, and Patrinia scabiosaefolia had a significantly higher germination percentage under light conditions than that under dark conditions. Only the germination percentage of Setaria viridis was significantly greater in darkness than in light. The germination percentage of seeds of other plants was not significantly different between the two conditions studied. The above results show that light is an important factor affecting plant seed germination on the abandoned cropland in the study region and darkness had an inhibitory effect on seed germination in most species. Thus, during the soil erosion process, sediment silting and shading are potential limiting factors for plant regeneration.