The Correlation between Maturity, Plant Architecture and Yield Related Traits of Soybean Cultivars in Northern China

Background: The traits of the time to flowering and maturity and other important agronomic traits, e.g., plant height, the numbers of nodes and branches are key factors for the adaptability of soybean cultivars to a certain photoperiodic length and ecological environment. Correlation analysis of these traits will facilitate fine-tuning of phenotyping procedure for each trait. Methods: In this field investigation during 2017-2020 at two experimental stations in Heilongjiang Province, northern China, a total of 1133 cultivars or accessions were phenotyped for traits related to maturity, architecture, e.g. plant height, the numbers of nodes and branches and yield. Statistical analysis was performed to reveal the correlation between different traits, years and locations. Result: R1 (days to the first flowering stage) and R2 (days to the fully flowering stage) are strongly stable traits among different years and different locations in this study. Significant correlations were identified between maturity trait, plant height, the numbers of nodes and branches. However, the traits of the height of the first effective node and the pod number per plant demonstrated some weak correlation among different years or with these maturity traits. Therefore, phenotyping procedures in this study can be directly applicable for accurate evaluation of maturity and plant architecture-related traits e.g. plant height, the numbers of nodes and branches.