Anatomical, agro-morphological and physiological changes in rice under cumulative and stage specific drought conditions prevailed in eastern region of India

•Multi-stage (seedling, vegetative and reproductive) drought tolerant rice genotypes were identified.•Multi-stage drought (MSD) affects physiological and biochemical functions of rice genotypes and stage specific responses were observed.•Physiological and biochemical basis of MSD tolerance was established in terms of PN rate, chlorophyll, protein and proline content.•Drought induced defective sugar mobilization leads to loss of pollen viability and finally grain yield.•Overall, the study provided a comprehensive understanding of multi-stage drought tolerance in rice.