Influence of heat stress during grain development on the wheat grain yield, quality, and composition

Wheat grain quality is a range of compositional and physical properties where threshold levels are set according to end-use requirements. The heat stress limits resource translocation to developing grains, causing a significant reduction in grain yield due to a decrease in the grain dimension and size. Moreover, heat stress also decreases the starch content; however, the grain gliadin content increases. Heat stress affects wheat quality by affecting grain appearance, size, weight, hardiness, protein, starch and mineral content, flour yield, and dough handling properties. However, the extent of change largely depends on the timing and severity of the stress and the type of wheat genotype. This review discusses the impact of heat stress on flower development, fertilization, grain development, and reproductive failure. The influence of heat on wheat grain yield, quality, and composition and associated biochemical and molecular mechanisms has been described.