NITROGEN UPTAKE, RECOVERY AND N-USE EFFICIENCY IN WHEAT (TRITICUM-AESTIVUM) AS INFLUENCED BY NITROGEN AND IRRIGATION LEVELS IN SEMI-RECLAIMED SODIC SOILS

A 2-year field experiment was conducted with wheat (Triticum aestivum L. emend. Fiori & Paol.) variety 'HD 2285' in semi-reclaimed sodic soi l of Karnal, comprising 4 levels each of nitrogen and irrigation. Sche duling irrigation at 1.2 irrigation water: cumulative pan evaporation (IW : CPE) ratio was better than other irrigation schedules in terms o f grain yield. With each increment of N level from 60 to 180 kg/ha, th ere was a significant increase in the grain yield as well as N uptake. Response to N of grain production at 1.2 IW : CPE ratio was significa ntly more than that at 0.6 and 0.9 IW : CPE ratios. The N content in s hoot at spike-initiation stage was higher in irrigated than in unirrig ated treatment, but reverse was true for N content in grain and straw at maturity. The N uptake through grain and straw was higher when irri gation was given at 1.2 IW : CPE ratio. Recovery of applied N and N-us e efficiency were maximum when irrigation was given at 1.2 IW : CPE ra tio along with 60 kg N/ha.