Removal of Apical Dominance in Common Buckwheat Improves Grain Fill and Yield

Poor grain filling and light grain test weight limit the grain yield potential of crops. The quality of grain filling is closely related to the grains on the position of the plant. This study assesses the positive effect of apical dominance removal treatment (ADR) on poor grain filling and the yield formation of common buckwheat (Fagopyrum esculentum Moench). Common buckwheat cultivar "Fengtian 1" was used to study the effects of ADR on grain filling, starch synthesis enzyme activities, endogenous hormone content, root morphology and physiology, and yield. Compared to no apical dominance removal (CK), the grain filling rate, abscisic acid (ABA), and indo-3-acetic acid (IAA) content of grains of the ADR treatment were increased by 54.9%, 26.2%, and 24.5%, respectively. The ADR treatment had better root growth and stronger antioxidant enzyme activity than the CK treatment. The grains per plant, grain weight per plant, and yield in the ADR treatment were 1.17, 1.34, and 1.12 times higher than the CK treatment, respectively. The findings indicate high starch synthesis activity, and high ABA and IAA contents accounted for the increased grain weight and filling rate of buckwheat grains in the ADR treatment. This research demonstrates potential for improved management in buckwheat production to increase the yield and improve the grain quality.