Nitrate leaching losses reduction, N-use efficiency optimization in Triticum aestivum L. and Oryza sativa L. rotation to improve production and soil reclamation rate with gypsum in salt-affected soil

Nitrogen management is the major challenge due to narrow understanding of yield and N uptake relationship on salt-affected soils. To address this problem, a lysimeter experiment for rice and wheat was conducted on salt-affected soil with two lower (15 and 30 %) and three higher N rates (15, 30 and 45 %) with 50 and 100 % SGR. NO3- leaching was greater with higher N rates (up to 188 mg Leachate-1) in rice as compared to wheat. After the harvesting of rice and wheat, maximum decrease in soil pHs (7.75 %), ECe (41.50 %), SAR (63.64 %) was with N130 G100 which indicated that applied gypsum 100 % SGR with higher N rate ameliorated the soil more efficiently as compared to 50 % SGR. The highest yields recorded with N130 + 100 % SGR. The highest NUE (15.88 g/g) was with treatment G100 N130 in rice but in wheat (NUE, 44.76 g/g) G100 N70 proved to be the best. It was concluded that G100 N130 proved to be the best and reduced the environmental risks.