Characteristics and evolutionary analysis of soybean varieties released in Henan Province in the last 40 years

Abstract To establish a phenotypic reference framework for breeding high‑yield and high‑quality soybean varieties in Henan Province, we analyzed agronomic traits of 194 soybean varieties released from 1985 to 2024. The number of released varieties increased over time. Hybrid breeding was the primary method, and the breeding system shifted from a research‑institute‑dominated pattern to a more diversified one. Growth duration showed a significant increasing trend (0.20 d yr⁻ 1 , R 2 = 0.438, P < 0.001); yield increased at a rate of 27.64 kg·ha⁻ 1 yr⁻ 1 (R 2 = 0.797, P < 0.001); number of pods per plant increased by 0.31 yr⁻ 1 (R 2 = 0.330, P < 0.001); whereas protein content decreased by 0.12% yr⁻ 1 (R 2 = 0.445, P < 0.001). Yield was positively correlated with number of pods per plant (r = 0.627, P < 0.01), growth duration (r = 0.534, P < 0.01), fat content (r = 0.567, P < 0.01), 100-seed weight (r = 0.353, P < 0.05), and plant height (r = 0.338, P < 0.05), and negatively correlated with protein content (r = -0.490, P < 0.01). These findings provide a phenotypic reference framework for breeding high‑yield and high‑quality soybean varieties in Henan Province.