Terminal heat stress in wheat and its mitigation options through agronomic interventions

Abstract

Since the beginning of century, the ambient temperature has increased and is predicted to rise further under prevailing climate change. Heat stress is the rigorous threat to wheat particularly during reproductive and grain filling stages which results into yield losses. At flowering stage, heat stress causes sterility of pollen and anther leading to underdeveloped embryo which in turn reduces
grain number, while heat stress during grain filling stage leads to reduced grain filling rate and in turn reduces grain weight and overall yield. There are various strategies for yield improvement under high temperature stress during reproductive phases in wheat but agronomic measures like timely sowing of wheat, retaining rice residue in field, irrigation during stress period, providing enough nutrition to the plants and spraying osmoprotectants can all help to reduce this stress.