Effect of different sowing dates on growth and yield of wheat (Triticum aestivum) cultivars under mid hill situation of West Bengal

A field experiment was conducted during the rabi 2008–09 and 2009–2010 at the Regional Research Station (Hill Zone) of Uttar Banga Krishi Viswavidyalaya, Kalimpong (1250 m amsl), to elucidate the effect of different sowing dates and cultivars on yield of wheat (Triticum aestivum (L.) emend Fiori & Paol.). The experiment was conducted in split plot design with 3 replications with treatments comprising five dates of sowing viz. Nov. 1, Nov. 15, Nov. 30, Dec. 15 and Dec. 30 in main plots and 6 different wheat cultivar viz. ‘HS 473’, HPW 236, ‘VL 875’, ‘HS 365’, ‘VL 832’, ‘PBW 343’ and ‘SKW 196’ in sub-plots. Sowing on November 15, significantly influenced most yield attributes and was at par with November 30 sowing, but significantly superior to later sowings. The highest grain yield was obtained with November 15 sowing (2.79 and 2.49 t/ha), which was at par with November 30, and November 1 sowings in first year and in second year this was statistically similar with all date of sowing except extreme late sown condition. Sowing in mid November gave 14.9 and 26.2% more grain yield over December 30 sowing. Amongst the cultivars, ‘HS 473’ was found to be best and gave significantly more grain yield than ‘HS 365’ (2.93 and 2.74 t/ha) and was at par with ‘VL 875’ (2.86 and 2.50 t/ha) and ‘PBW 343’ (2.89 and 2.61 t/ha). More biomass production was recorded with early November 15 sowing, which was at par with November 30 sowing. Within the cultivars, maximum biomass production was recorded with ‘HS 473’ (7.78 and 7.28 t/ha) and was statistically at par with ‘VL 875’, ‘‘SKW 196’’ and ‘PBW 343’. Uptake of NPK was most with ‘PBW 343’, which was at par with ‘HS 473’. Maximum net return (24,926 and 23,192/ha, respectively) recorded with November 15 sowing, followed by November 30 sowing. This treatment also recorded higher B: C ratio (2.11 and 2.03, respectively). Amongst cultivars, maximum net return (26,986 and 24,368/ha) and B: C ratio (2.21 and 2.08) was recorded with cultivar ‘HS 473’ followed by ‘PBW 343’ and ‘‘SKW 196’’.