Qualitative Traits of Heat Stressed Bread Wheat (Triticum aestivum L.) were Improved by Exogenous Potassium Signaling

Deterioration of grain quality of wheat due to high temperature at reproductive stages has become a global issue. The current study deals with (i) comparative sensitivity of terminal stages of wheat towards heat and its impacts on quality of grain (ii) quantifying the foliar potassium to alleviate adverse implications of heat on qualitative traits of wheat grain (iii) determining the type and strength of correlation among qualitative traits and yield of heat stressed wheat. The experiment was carried out over 2 years. The trial was laid out in a randomized complete block design with split structure of treatments. Treatments were consisted of heat imposition in main plot viz. H0 = no heat imposition (control); H1 = Heat from spike to grain filling; H2 = Heat from flowering to grain filling and exogenous potassium in sub plots viz. 0, 15, 30, 45, 60 g L- 1. 'Heat from spike to grain filling' proved more detrimental than 'no heat stress' and 'heat from flowering to grain filling' for quality, rheological and yield traits. Foliar potassium at 60 g L- 1 improved grain yield, gluten contents, dough departure and arrival times, dough stability, pasting temperature, setback and final viscosities and decreased damaged starch and dough peak compared to other doses. Strong associations of qualitative traits with grain yield were quantified. Conclusively, 'heat form spike to grain filling' proved more damaging while 60 g L- 1 foliar potassium effectively reduced heat-triggered damages to grain quality.