Evaluation of the Relationship between Phenological Traits and Yield per Plant and the Application of These Traits in Selection and Grouping Quinoa Genotypes

This research aimed to study the relationship between different phenological traits with grain yield and investigate the effectiveness of these traits in single plant selection in quinoa, which was done based on a randomized complete block design. Grain yield per plant showed the most significant positive correlation with day-to physiological maturity and grain filling period and the most significant negative correlation with day-to-ten leaves and day-to germination.  Day-to physiological maturity, day-to-ten leaves (with negative coefficient), and grain filling period were entered into the regression model. The two traits of day-to-ten leaves and day-to physiological maturity had the most direct negative and positive effects on grain yield changes, respectively. The most indirect positive effect was related to the grain filling period, due to the increase in day-to physiological maturity. The distribution of genotypes in all four biplot areas indicated high genetic diversity of genotypes. The favorite genotypes (16, 8, 15, and 14) had the highest amount of traits of day-to physiological maturity, grain filling period, and day-to milky grain and were located in the favorable area of the biplot. According to the results of the cluster analysis, these genotypes were located in the "grain yield cluster". On the contrary, unfavorable genotypes (2, 7, and 12) had the highest day-to-ten leaves, day-to-germination, and day-to-four leaves. In general, the selection to increase the day-to physiological maturity and the grain filling period and the selection against the day-to-ten leaves and the day-to germination will improve the yield per plant of quinoa.