Analysis of the relationship between agronomic traits and yield of Chenopodium quinoa

In this study, 14Chenopodium quinoa cultivars (strains) were selected as research materials. The whole growth period, plant height, stem diameter, fresh weight per plant, grain weight per plant, 1000-grain weight, spike color, stem color, seed color, and spike type of quinoa were observed and the relationship between agronomic characteristics and quinoa yield was determined using correlation, principal component, multiple linear regression, path, and cluster analyses. The results revealed abundant variation in the agronomic traits of C. quinoa, with a coefficient of variation ranging from 16.31% to 46.18%. Grain weight per plant was positively correlated with both the fresh weight per plant and 1000-grain weight (P < 0.01), negatively correlated with the whole growth period and plant height, and positively correlated with the stem diameter. Three principal components, the morphological, yield, and growth cycle factors, were extracted using principal component analysis, with a cumulative contribution rate of 81.107%. Path analysis showed that the 1000-grain weight and fresh weight per plant limited the grain weight per plant. Q-type cluster analysis of 14 different quinoa cultivars (strains) was carried out using the group-average method. Using a distance of 3 between clusters, the quinoa cultivars could be divided into six groups. The 1000-grain weight and fresh weight per plant were the main factors affecting quinoa yield, per plant. This comprehensive evaluation system for quinoa, established using principal component and cluster analyses, can provide a theoretical basis for the screening and utilization of quinoa cultivars (strains).