Response of late sown wheat (Triticum aestivum) to row spacing cum population densities and levels of nitrogen and irrigation in north western Rajasthan

Abstract

A field investigation was conducted during the winter (rabr) season of 1998 99 and 1999 2000, to find out the optimum row spacing cum population density, nitrogen and irrigation level requirement for late sown wheat (Trii cum aestivum L. emend. Fiori Paol.). Narrow row spacing of 15 cm using 205 kg seedha resulted in significant higher grain yield (29.9 and 27.9 qlha) compared with normally used spacing of 22 cm with 140 kg seedha. Sig nificant increase in yield was recorded up to 150 kg Nlha and it did not differ significantly with that obtained with 180 kg Nlha. Irrigations at IW : CPE 0.8 with each irrigation of 6.0 cm, recorded significantly higher grain yield (29.5 and 27.6 qlha) than that of irrigation at IW : CPE 0.6, but it was at par with that of irrigation at IW : CPE 1 .O. Similarly, 150 or,180 kg Nlha recorded higher water use efficiency (8.5 and 7.7 kglha mm). Increase in irrigation levels decreased water use efficiency. The highest water use efficiency of 76.4 and 66.9 kg grainlha cm during 1998 99 and 1999 2000, respectively, was recorded with narrow spacing. Narrow row spacing recorded higher net return (Rs 11,729 and 101 56)lha and benefit : cost ratio (2.2 and 2.0). Nitrogen levels of 150 kglha gave the highest net return (Rs 12, 203 and 10,678) and benefit : cost ratio followed by 180 kg and 120 kg Ntha. The high est net return and benefit : cost ratio were obtained with 6 cm irrigations applied at IW : CPE ratio 1.0 and IW : CPE ratio 0.8 in 1998 99 and 1999 2000, respectively, schedule for a wheat after a 10 cm pre sowing irrigation. Inter action effect of spacing and nitrogen, nitrogen and irrigation and spacing and irrigation had significant effect on grain yield in both the years.