Photoperiod Response of Annual Wild Species and Cultivated Chickpea on Phenology, Growth, and Yield Traits
Frequent utilization of wild Cicer species in chickpea (Cicer arietinum L.) improvement programs, as well as the regeneration of these wild species for efficient conservation in genebanks, is hindered due to photoperiod and/or temperature sensitivity (vernalization). In this study, the response to four extended photoperiod treatments (15, 18, 21, and 24 h) was compared with a control (12 h) for phenology and growth in terms of reduction in number of days to first flowering, as well as for yieldrelated traits in cultivated chickpea and seven annual wild Cicer species. The study revealed that wild Cicer species required long photoperiods (varying from 15 to 18 h) for transition from the vegetative to reproductive phase. Optimum photoperiods also improved agronomic traits such as pod number and seed yield per plant. Of the photoperiods studied, 18 h was the most appropriate photoperiod treatment for both reducing the vegetative phase and for efficient regeneration in C. reticulatum Ladiz. Fifteen hours was the most appropriate photoperiod in C. judaicum Boiss. and C. yamashitae Kitamura. Both 15 and 18 h were the most appropriate photoperiods in C. bijugum K.H. Rech. and C. pinnatifidum Jaub. & Sp., depending on the objective (15 h for regeneration and 18 h for reducing vegetative phase). Cicer chorassanicum (Bunge) M. Pop. and C. cuneatum Hochst. ex A. Rich. showed a weak response to all the extended photoperiod treatments. These results contribute to enhanced utilization of wild Cicer species for chickpea improvement through synchronization of flowering facilitating hybridization and for efficient regeneration by using species specific extended photoperiod treatments.