Comprehensive evaluation of agronomic, processing, nutritional and functional properties of 22 main-cultivated adzuki bean varieties in China and identification of elite varieties for different applications.

Adzuki bean (Vigna angularis) is an important medicinal and edible legume with high nutritional and functional value. However, a systematic multi-dimensional quality evaluation system for mainstream varieties remains insufficient, restricting targeted breeding and industrial diversified utilization of adzuki bean. This study comprehensively assessed the agronomic, nutritional, processing and functional traits of 22 dominant Chinese adzuki bean varieties to screen promising candidate germplasms for specific applications. Multiple indices covering agronomic traits, mineral nutrition, seed color, processing quality and antioxidant capacity were determined, and 18 core indices were analyzed via principal component analysis (PCA). Results revealed abundant phenotypic variation across all traits, with pods per plant, isoflavone monomers and soluble sugar showing the most pronounced phenotypic variation. PCA ranked Baihong 2, Jihong 8 and Jihong 13 as the top three varieties under the tested conditions, and identified special-purpose cultivars including high-yield Jihong 9218, isoflavone-rich Baohong 8824 and antioxidant-rich Kenjianhong. This study established a multidimensional quality evaluation framework, providing scientific reference for promising cultivar screening, targeted breeding and sustainable industrial development of adzuki bean.