供氮水平对引黄灌区春小麦氮平衡及产量和加工品质的影响

Effects of N application rates on N balance,grain yield and industrial quality of spring wheat

以宁春4号为材料研究了不同供氮水平对土壤-作物体系氮平衡和春小麦产量和品质的影响,结果表明：氮肥利用率随施氮量的升高呈下降趋势,氮肥利用率在18.2%-27.2%之间,平均为23.2%;氮素表观损失率为31.2%-52.1%,随施氮量增加而增加。在0-240 N kg/hm2范围内,小麦籽粒产量和赖氨酸含量随施氮量增加而增加,当施氮量达到360 kg/hm2,籽粒产量和赖氨酸含量不再增加;施用氮肥可以明显改善小麦的加工品质,表现为湿面筋含量提高,容重和弱化度降低。综合考虑小麦的产量、品质以及土壤-作物氮素平衡状况,在本试验条件下,当季春小麦施氮量不应超过240 kg/hm2。

Field experiments were conducted with four N level treatments by N0： N 0 kg/hm2,N120： N 120 kg/hm2,N240： N 240 kg/hm2,and N360： N 360 kg/hm2 respectively to study the effects of different N application rates on N balance,grain yield and industrial quality of spring wheat in the irrigated areas with the Yellow River water in Ningxia.The results showed that N fertilizer could significantly increase the yield and improve the industrial quality of spring wheat.The grain yield and lysine content were the highest by N240 treatment,but when the amount of N application was greater than 240 kg/hm2,the grain yield and lysine content decreased by 1.9% and 5.5% respectively.Apparent N recovery was decreased with N rates increasing,which was ranged from 18.2%~27.2%.N balance results showed that N apparent losses were ranged from 31.2%~52.1% in treatment N120,N240 and N360.Considering high grain yield,industrial quality,apparent recovery of N fertilizer and low apparent losses rate,the amount of fertilizer N should be controlled under 240 kg/hm2 during the wheat growing period.