Dry-matter accumulation-at pre-and post-anthesis and yield of wheat (Triticum aestivum) as affected by temperature stress and genotypes

A field experiment was carried out during 2000-2001 and 2001-2002 to study the effect of sowing time and genotypes on biomass accumulation and yield in wheat (Triticum aestivum L. emend. Fiori & Paol.) at Pantnagar, Uttaranchal. Normal sown crop (22 November) accumulated significantly higher dry matter in different plant parts and yielded higher than late-sown crop (22 December). Leaf dry weight increased up to 10 days after anthesis and declined thereafter, whereas stem, spike and total dry weight increased up to maturity without showing any decreasing pattern. The highest spike dry weight at all the stages was recorded in 'UP 2425', whereas 'WH 542' had minimum spike dry weight. At maturity, the highest total dry weight was recorded in 'PBW 343' during both the years. Variety 'PBW 343' performed better and 'WH 542' yielded lower than other varieties under normal sown condition, while 'UP 2425' followed by 'UP 2338' was highest grain-producing variety in December-sown crop.