1Former Ph.D Student, Division of Agronomy, Indian Agricultural Research Institute, New Delhi, India.
2Director, ICAR-Directorate of Weed Research, Jabalpur, India.
3Assistant Professor, Department of Soil Science, Ramin Agricultural and Natural Resources University, Iran.
The effect of tillage, crop establishment and weed management was studied on the performance of wheat grown after soybean at New Delhi, India during 2010-11 to 2011-12. Sixteen treatment combinations involved 2 tillage, viz. conventional tillage (CT) and zero tillage (ZT), two crop establishment practices, viz. raised-bed and flat-bed and four weed management, viz. isoproturon + hand weeding, mesosulfuron+ iodosulfuron, soybean stover + isoproturon and unweeded control. Population density and dry weight of weeds was significantly more under raised-bed than flat-bed, particularly under ZT condition, while under flat-bed, the differences between CT and ZT were on par. Weed control efficiency was the highest (90.7-91.4%) under isoproturon + hand weeding and significantly higher than other treatments (86.5-90.2%). Yield losses under unweeded control were 23.1-26.1%. Grain yield of wheat under ZT-flat-bed (4.46-4.73 ton ha-1) was equal to that under CT-flat-bed (4.44-4.79 ton ha-1), which was comparatively more than raised-bed conditions. All weed control practices were on par and equally effective improving the yield of grain (19.2-27.5%) as well as straw (14.0%) compared with unweeded control. Nutrient uptake by crop decreased linearly with increase in nutrient removal by weeds. The highest net benefit: cost ratio was under ZT-flat-bed and mesosulfuron + iodosulfuron (3.04) followed by soybean stover mulch + isoproturon (2.84). It was concluded that wheat can be grown underzero-till condition with post-emergence herbicide application for realizing higher productivity and profitability in the Indo-Gangentci plains of India.