Profiling and associations of seed nutritional characteristics in Chinese and USA soybean cultivars

Abstract

Soybean is an important oilseed crop both in China and the USA owing to its nutritional and functional characteristics. The formation of nutritional components in soybean is influenced by the genetic background of cultivar as well as environmental factors. Here, we profiled protein, oil, fatty acids, soluble sugars and isoflavone in 218 Chinese and 115 USA soybean cultivars which were grown across three locations for two years in China. Significant differences (p < 0.05) were observed among the cultivars, countries of origin and maturity groups for all the nutritional characteristics measured. Higher levels of oil (20.5%), linoleic acid (56.4%), sucrose (58.6 mg g−1), total soluble sugars (109 mg g−1) and total isoflavone (3,161.8 μg g−1) were observed in USA cultivars, while higher levels of protein (42.4%) and oleic acid (23.2%) were observed in Chinese cultivars. From the principal component analysis, protein, oil, oleic acid, linoleic acid and isoflavone were identified as the major discriminative characteristics in the soybean cultivars. Furthermore, correlation analysis presented various beneficial associations among the different nutritional traits. The nutritional characteristics varied in their associations with the geographical factors (latitude, longitude and altitude), indicating that the origin of the cultivars has a pronounced effect on the nutritional characteristics. This study reveals the profiles of nutritional characteristics of Chinese and USA soybean cultivars and also identified unique cultivars that can be utilized for various industrial uses and breeding programs aimed at improving soybean nutritional characteristics.