Performance of late sown wheat crop under different planting geometries and irrigation regimes in arid climate

Proper orientation of plants in the field and management of soil moisture for appropriate utilization of land, water and environmental resources plays a significant role in the optimum development and functioning of vital plant organs. A two factor field experiment was conducted for two consecutive crop growth seasons viz. 2006–07 and 2007–08 at Research and Demonstration Farm, Regional Agricultural Economic Development Centre (RAEDC), Vehari, Pakistan to make a comparison of four different planting geometries viz. planting in 22 cm apart rows under conventional, minimum and zero tillage, respectively and planting in 11 cm apart rows under conventional tillage system. Wheat cultivar, Inqlab-91 was planted late in December. Crop was subjected to five irrigation levels in which irrigation was applied equivalent to 120%, 100%, 80%, 60% or 40% of ETo. Lower soil bulk density and penetration resistances at 10–20 cm soil depth were recorded with conventional tillage with either narrow or wider row spacing as compared to other planting geometries. The maximum values for LAI, LAD, TDM, productive tillers (m−2), 1000-grain weight and grain yield were recorded with planting geometry having 11 cm apart rows under conventional tillage system along with irrigation level of 120% ETo that remained statistically at par with the same planting geometry subjected to the irrigation regime of 100% ETo. This planting geometry also resulted in minimum weed fresh biomass. It is concluded that late planted wheat crop planted in 11 cm wide rows under conventional tillage irrigated @ 100% ETo may serve as an appropriate technology for enhancing the wheat productivity of late sown wheat crop under limited water supplies.