Inheritance of time to flowering in chickpea in a short-season temperate environment

Time to flowering is central in determining the adaptation and productivity of chickpea in short-season temperate environments. We studied the genetic control of this trait in three crosses, 272-2 x CDC Anna, 298T-9 x CDC Anna, and 298T-9 x CDC Frontier. From each cross, 180 F-2 plants and parents were evaluated for time to flowering under greenhouse conditions. In summer 2004, multiple generations including P-1, F-1, P-2, F-2, and F-2:3 ( also called MG5) were evaluated for time to flowering under field conditions. The data on time to flowering in the F-2 populations were continuous in distribution but deviated from normal distribution. The F-2:3 families derived from this showed a bimodal distribution for time to flowering, a typical case of major-gene inheritance model with duplicate recessive epistasis. A joint segregation analysis of MG5 also revealed that time to flowering in chickpea was controlled by two major genes along with other polygenes. Late flowering was dominant over early flowering for both major genes with digenic interaction between them, mainly an additive x additive type. This information can be used to formulate the most efficient breeding strategy for improvement of time to flowering in chickpea in short-season temperate environments.