Short internode,double podding and early flowering effects on maturity and other agronomic characters in chickpea

Chickpea is an indeterminate species, which continues to flower and set new pods over a long period under wet and cool growing conditions, resulting in excessive canopy development and delayed maturity. We hypothesized that the chickpea's long season requirement could be reduced through introgression of short internode, double podding and early flowering. Four populations E100Ym/CDC Anna, 272-2/CDC Anna, 298T-9/CDC Anna, and 298T-9/CDC Frontier were developed to test this hypothesis with the first parents of each cross being the donor of the short internode, double podding and early flowering traits, respectively. Also, the donor parents E100Ym, 272-2 and 298T-9 were intercrossed. Segregating populations of F₂ to F_3:6 generations were then evaluated under greenhouse and field conditions. When expressed well, double podding significantly reduced time to maturity as compared to the single podding counterparts. The best double podding lines were about 1 week earlier maturing than the early parent and standard checks. Days to flowering (DF) was positively associated with days to maturity (DM) (r = 0.44, P < 0.001), and partial path analysis revealed that DF contributed to DM mainly via days to first pod maturity (DFPM). In the two early flowering populations 298T-9/CDC Anna and 298T-9/CDC Frontier, DF determined about 32% of the variation in DFPM. Conversely, the short internode trait had an undesirable effect, in that all the short internode segregants were too late to mature. In conclusion, the alleles for double podding and early flowering may be used to improve early maturity in chickpea and subsequently minimize the risks associated with the production of this crop in environments where the growing conditions allow excessive crop canopy development, as in the Canadian prairies.