Terminal drought-priming improves the drought tolerance in desi and kabuli chickpea

Chickpea productivity, throughout the world, is being threatened by water deficit. In this study, the influence of terminal drought-priming on the performance of desi and kabuli chickpea types was evaluated under drought and well-watered conditions. During first season, chickpea plants were grown under well-watered conditions (75% water holding capacity). At flower initiation, drought was imposed in half of the pots by maintaining soil moisture at 50% water holding capacity while remaining half continued to grow under well-watered conditions. Terminal drought stress significantly affected the seed composition of both chickpea types as indicated by increase in total proteins (10%), zinc (9.5%), potassium (3.2-0.9%), calcium (2.5-1.3%), and total soluble phenolics (4-57%) than the plants raised under well-watered conditions. During second growing season, chickpea seeds collected from well-watered and droughted source were grown in soil filled pots under well-watered and drought conditions maintaining soil moisture at 75% and 50% water holding capacity, respectively. Drought suppressed the stand establishment, seedling growth, total chlorophyll contents, rate of photosynthesis, PSII efficiency, a-amylase activity, sugar metabolism, and trehalose contents of both chickpea types. Chickpea types also differed in their response to drought; kabuli chickpea type was more affected by drought than the desi type. The desi chickpea type had better stand establishment and growth than the kabuli chickpea type. However, under drought, terminal drought-priming improved the performance of both types of chickpea; nonetheless the improvement was more pronounced in desi chickpea types. Terminal drought-priming stimulated the build-up of trehalose, proline and total phenolics, and improved the germination metabolism, which assisted improve drought tolerance in desi chickpea. In conclusion, changes in seed composition induced by drought-priming improved drought tolerance in chickpea owing to better germination and carbon assimilation, and more accumulation of trehalose, free proline and total soluble phenolics.