Effect of early sowing, N levels and seed rates on yield and yield attributes of different wheat (Triticum aestivum) varieties

A field experiment was conducted for three consecutive years during 2007 to 2010 at Karnal by using three high yielding disease resistant wheat [Triticum aestivum (L.) emend. Fiori & Paol] varieties namely ‘PBW 502’, ‘HD 2687’ and ‘DBW 17’ with two sowing time (last week of October and mid November), two seed rates (100 and 125 kg/ha) and two N rates (150 and 200 kg/ha) and replicated thrice. Pooled analysis revealed that early sowing produced 10.06% higher grain yield than normal sowing due to higher biomass, spikes/m2, harvest index and thousand grain weight. This was achieved due to 15 days earlier flowering in early sown, which provided more conducive environment for proper growth and development of wheat grain than timely sowing. Among varieties, ‘HD 2687’ produced significantly higher grain yield than other varieties. Application of 50 kg more N/ha than recommended dose exhibited significantly higher grain yield, whereas 25% higher seed rate application showed no significant effect on grain yield. October sowing recorded higher gross returns (9.6%), net returns (19.3%) and benefit cost ratio (2.01) than mid November sowing.