Keywords : Wheat, seeding method, mulching, nitrogen application, yield

Yield stability of wheat under different combinations of seeding methods, mulching and time of nitrogen application was assessed by conducting field studies in the farmer’s field, Bairahani, east Chitwan and in the research block of Institute of Agriculture and Animal Science (IAAS) Rampur, Chitwan in the wheat seasons of 2003/04 to 2005/06. The experiments were carried out in factorial Randomized Complete Block Design which consisted of two seeding methods (surface seeding and conventional seeding); two levels of mulch (no mulch and rice straw mulch @ 4 mt/ha) and two different times of nitrogen application (½ at sprouting+ ½ at CRI and ½ at CRI + ½ at 40 DAS) with four replications at Bairahani and three replications at Rampur. The seeding methods significantly affected growth, yield attributing characters and yield of wheat. In surface seeding, values of these characters were lower in the first year but, from the second year, they were gradually increased and were significantly higher than those in conventional seeding in third year. Significantly higher yield was obtained in surface seeding treatments than that in conventionally tilled treatments in sandy clay loam soil at Rampur from the second year where as that was obtained in clay loam soils at Bairahani only after third year. Similarly, higher no. of tillers at 30 DAS and lower weed dry matter were found in mulch treated plots from the first year, which ultimately promoted growth, yield attributing characters and yield as compared to no mulch. Likewise, time of nitrogen application significantly affected the growth and yield of wheat. Application of ½ N at sprouting+ ½ N at CRI produced significantly higher yield. Similarly, the interaction effect of such time of nitrogen application with mulch in surface seeding significantly increased yield in later years than in the first year, where as in conventional seeding no such increment in yield was observed. Application ½ N at sprouting+ ½ N at CRI with mulch in surface seeding increased yield by 80.64% (1.86 mt/ha vs. 3.36 mt/ha) at Bairahani in third year. In contrast, at Rampur, yield was increased by 46.64% (2.98 mt/ha vs. 4.31 mt/ha) in second year. Thus, cultivation of wheat with the application ½ N at sprouting+ ½ N at CRI with mulch in surface seeding condition may be technique for getting higher yield and net return in the long run.