Determinate growth habit of grain legumes: role in domestication and selection, genetic control

Abstract

This review is devoted to the analysis of molecular genetic mechanisms of controlling the type of growth habit of grain legumes (pea, soybean, common bean, vigna); it provides information about known homologous genes TFL1, LFY, AP1, FUL, FT, and FD. Significant changes in plant architecture were during domestication of grain legumes. Many wild relatives of legumes are characterized by an indeterminate growth habit type, cultivated plants are characterized by indeterminate and determinate types. In plants with a determinate growth habit type, terminal inflorescence is formed at transition from the vegetative phase to the reproductive phase. These plants are characterized by a complex of features: simultaneous maturation of beans, resistance to lodging, etc. In indeterminate type of growth habit, the apical shoot meristem remains active during plant life. The main genes responsible for the plant transition to flowering are the homologs of the Arabidopsis genes LFY, TFL1, AP1. TFL1 gene is responsible for maintenance of growth of the shoot apical meristem; its homologs were identified in pea (PsTFL1a), soybean (Dt1/GmTFL1), common bean (PvTFL1y), cowpea (VuTFL1). The identification and characterization of the genes responsible for the type of stem growth habit are necessary for the successful selection of modern varieties suitable for mechanized cultivation. Design of molecular markers that diagnose this important breeding trait at early plant development stages, will help to determine the type of stem growth habit.