Effects of Shading on Leaf Morphology and Function of Wild Soybean

In order to clarify the changing trend of leaf morphology and function of wild soybean（Glycine Soja） under shading conditions, we studied the effects of shading on leaf morphology, photosynthetic characteristics, chlorophyll content and chlorophyll fluorescence characteristics of wild soybean materials from five collection areas. The results showed that the morphological characteristics of wild soybean leaves were different under shading treatments. The leaf size and leaf color value changed after shading treatment. The leaf area and leaf color value increased when the shading rate was 50%, but decreased when the shading rate continued increasing. The photosynthetic rate, transpiration rate, stomatal conductance and intercellular carbon dioxide concentration of wild soybean changed after shading. Different shading rate conduced on different materials induced different variation trends, different materials showed sensitive or insensitive light response. With the shading rate increasing, the chlorophyll a, chlorophyll b and carotenoid contents of each materials increased firstly and then decreased. The chlorophyll a/b showed a decreasing trend, and the higher the shading rate, the smaller the chlorophyll a/b. Wild soybean had the characteristics of shade plants, and both normal illumination and shading will lead to the decrease of Fv/Fm, resulting in the phenomenon of light stress. Different materials had different conversion efficiency of light energy. According to the comparison of phenotypic traits and photosynthetic performance, after shading, A5 material had a smaller change in leaf area, increased photosynthetic rate, and maintained a higher leaf color value and Fv/Fm ratio, so A5 was a shade-resistant material.