Combating Heat Stress in Late Sown Wheat through Pre-Sowing Seed Priming

The goal of the current study was to evaluate the effectiveness of various seed priming methods in enhancing wheat growth and yield when sown late. Therefore, a field experiment was conducted at the Agronomy Field Laboratory, Bangladesh Agricultural University, Mymensingh, following a Split-plot design with three replications. The experiment comprised two factors, Factor A: wheat sowing date viz., (i) 30 November; (ii) 15 December; (iii) 30 December; Factor B: seed priming agent namely, (i) control (no priming); (ii) hydro priming; (iii) priming with 20000 ppm CaCl₂; (iv) priming with 20000 ppm KCl; (v) priming with 15000 ppm KNO₃; and (vi) priming with 40000 ppm Mannitol. The study found that BARI Gom-33’s grain yield was highest (3.06 t ha^-1) when sown on 30 November, which was reduced by 39.87% and 64.37%, respectively, by late and very late sowing. Grain yield was significantly increased by seed priming, especially with CaCl₂, by 0.66 t ha^-1 when compared to the control. Moreover, when CaCl₂ priming was used on November 30, the highest grain yield was obtained (3.37 t ha^-1). In contrast, when no priming was used on December 30, the lowest yield (1.11 t ha^-1) was obtained. Consequently, to mitigate the effects of high temperatures, wheat should be sown by November 30th, ideally with 20,000 ppm of CaCl₂.