PhD defence Iftikhar Khan
Iftikhar Ahmad Khan (GREEN)
Promotor: Prof. J.T.M. Elzenga; copromotor: Dr H. van Veen
Cold stress effects on morpho-physiological traits in chickpea (Cicer arietinum L.) genotypes at early developmental stages
Chickpea, often called the "poor man's meat," is a vital, protein-rich crop grown globally. It serves as a low-cost alternative to animal-based protein and enhances soil quality through nitrogen fixation. However, chickpea cultivation faces challenges, particularly cold stress during early growth stages, which can lower yields. This study focused on understanding how two main chickpea types, Desi and Kabuli, respond to cold temperatures during the seedling stage to identify traits that could aid in breeding cold-tolerant varieties. The research involved testing 22 genotypes at both normal (23°C) and suboptimal (15°C) temperatures. Cold stress significantly reduced growth across all genotypes, especially affecting shoot and root weights. However, Desi types performed better under cold conditions compared to Kabuli types. Six varieties were then selected for further analysis of their root and physiological traits.
Cold temperatures severely inhibited early root growth, particularly the lateral roots. However, early root development did not predict cold tolerance during later growth stages. Detailed root analysis revealed that Desi varieties had beneficial traits, such as a greater number of lateral roots, larger lateral root diameter, and thicker root vessels, which appeared to contribute to their cold tolerance. Additionally, the physiological responses between one Desi and one Kabuli variety showed that Desi types had higher photosynthesis rates, less chlorophyll damage, and better growth under cold stress. These findings suggest that selecting for specific root and physiological traits could enhance cold tolerance in chickpeas, though further research is needed to develop cold-resistant varieties.