Genetics of flowering time in chickpea and its bearing on productivity in semiarid environments

Chickpea (Cicer arietinum L.),a grain legume of Near-East origin has a unique natural history. The crop cycle in most of its traditional growing areas is completely different from the autumn germination, spring flowering, and summer maturation of its wild progenitor Cicer reticulatum Ladiz., in eastern Turkey. Millennia of summer cropping in the Near-East and later dissemination into the lower latitude growing areas of eastern Africa and the Indian subcontinent,as a postrainy season crop, had profound effects on allelic variation in major adaptive loci of chickpea. In this chapter we discuss the consequences of the traditional cropping practices on the flowering time genes of chickpea. The recently identified genes for flowering time are described with special reference to their effect on chickpea adaptation, seed weight, seed yield, and stability under semiarid Near-East and Indian subcontinental growing environments. It is suggested that the genetic research on flowering time of this species and its wild relatives needs much attention, as only two genes affecting this trait are identified so far. Genes allowing a reduced crop cycle will provide pathways for new cropping systems and increased population density. Reduced crop duration may also help chickpea escape damage by the major biotic and abiotic stresses that mostly affect the crop at flowering and podding stages. It is concluded that the relatively simple inheritance of flowering time opens up new possibilities for breeding high yielding and stable chickpea cultivars for the semiarid and arid regions globally.