The Difference Research On Mineral Content And Photosynthetic Characteristics Among Soja

Wild soybean, semi-wild soybean, and cultivated soybean are classified as Glycine Soja belonging to Leguminosae or Papilionoideae. Although these plants are of the same species, wild soybean is regarded as the ancestor of cultivated soybean. Among these plants, cultivated soybean is considered as a valuable economic crop; cultivated soybean is also domesticated as wild soybean. Semi-wild soybean exhibits combined traits of wild soybean and cultivated soybean. Nevertheless, these three plants differ genetically and vary in morphological characteristics, structures, and adaptability traits.In this study, different experimental materials, namely, salt-tolerant wild soybean(tongyu06311), salt-sensitive wild soybean(huinan06116), semi-wild soybean, and cultivated soybean, were selected. The seeds of these experimental materials were sown in Gongzhuling City, Jilin Province, China, by using a standard field management mode. Functional leaves were collected in different growth stages(S1, seedling stage; S2, initial bloom stage; S3, full bloom stage; S4, pod-bearing period; and S5, seed-filling period). These leaves were then used to determine cation and anion contents. Chlorophyll content, chlorophyll fluorescence parameters, gas exchange parameters, and carbohydrate content were also identified in initial bloom stage. This study aimed to reveal the physiological metabolic pattern of Soja plant evolution.Exposed to natural environment pressure, salt-tolerant wild soybean absorbed higher average H2PO4- and Cu2+ contents than salt-sensitive wild soybean. Salt-tolerant wild soybean also exhibited improved resistance compared with salt-sensitive wild soybean. Chlorophyll a, chlorophyll b, chlorophyll(a+b), and carotenoid contents, Fv/Fm, Y(NPQ), NPQ, leaf net photosynthetic rate(pN), stomatal conductance(gs), intercellular CO2 concentration(Ci/Ca), transpiration rate(E), water-use efficiency(WUE), and carbohydrate content were higher. Thus, photosynthetic characteristics of salt-tolerant wild soybean showed more advantages than salt-sensitive wild soybean. In artificial domestication and breeding, the average NO3-, Mo4+, Fe2+, H2PO4-, Cu2+, and SO42- contents absorbed by semi-wild soybean and cultivated soybean were significantly lower than those absorbed by salt-sensitive wild soybean; by contrast, the average Ca2+ and B3+ contents absorbed by semi-wild soybean and cultivated soybean were significantly higher than those absorbed by salt-sensitive wild soybean. This result showed that changes in semi-wild soybean were similar to those of cultivated soybean; conversely, changes in semi-wild soybean and cultivated soybean were different from those of salt-sensitive wild soybean. In photosynthetic characteristics, chlorophyll b, carotenoid contents, Fv/Fm, pN and E of salt-sensitive wild soybean, semi-wild soybean, and cultivated soybean gradually increased. Therefore, The correlation analysis of mineral element absorption and photosynthetic characteristics in initial bloom stage showed that the trend of H2PO4-,SO42-,K+,Mg2+,Mo4+,Mn2+ and photosynthetic characteristics were significant difference under natural selection and artificial domestication.After long-term natural selection and artificial domestication occurred, mineral contents and photosynthetic characteristics of Soja indicated that these plants gradually adapted to different habitats and human needs. Our results contributed to our understanding of evolutionary functional changes in Soja plants.