秸秆还田与氮肥减施对旱地春玉米产量及生理指标的影响

Effect of straw incorporation and nitrogen fertilizer reduction on spring maize yield and eco-physiological traits in an arid farming area

通过在陇东黄土旱塬雨养农业区进行的3年田间定位试验,研究了秸秆还田与氮肥减施对旱地春玉米产量、水分利用效率及生理指标的影响。试验设置6个处理,分别为:1)常规施氮(F,225 kg·hm-2);2)秸秆还田(TS,9000 kg·hm-2);3)F+TS;4)80%F+TS;5)60%F+TS;6)不施肥不还田(CK)。结果表明:与F+TS相比,不同年份秸秆翻压还田与减量20%~40%氮肥配施均表现出产量和水分利用效率不同程度的增加,差异不显著,平均产量和水分利用效率大小变化顺序均为80%F+TS>60%F+TS>F+TS>F>TS>CK。其中80%F+TS平均产量和水分利用效率较F+TS增加9.9%、8.2%,较CK增加46.9%、52.4%,60%F+TS较F+TS增加2.6%、3.7%,较CK增加37.2%、46.1%。同时,秸秆翻压还田与减量20%~40%氮肥配施提高了春玉米全生育期干物质积累量,改善了产量性状和拔节期玉米光合性能及叶片叶绿素相对含量(SPAD)。因此,在陇东黄土旱塬雨养农业区,60%~80%F+TS处理即秸秆翻压还田与氮肥减量20%~40%的配施方式是该地区最优施氮栽培方式。

A 3-year field experiment was conducted in a dryland area on the Loess Plateau,eastern Gansu Province,China,to study the effects of straw incorporation and nitrogen fertilizer reduction on the yield,water use efficiency(WUE),and physiological traits of spring maize(Zea mays).The six treatments included normal fertilization with nitrogen fertilizer at 225 kg N·ha-1(F),total straw incorporation of 9000 kg dry matter·ha-1(TS),F+TS,80%F+TS,60%F+TS,and no fertilization or straw incorporation(control,CK).Compared with the F+TS treatment,both the 80%F+TS and 60%F+TS treatments increased the yield and WUE of spring maize.However,the differences in the grain yield and WUE were not significant among the F+TS,80%F+TS,and 60%F+TS treatments.The treatments could be ranked,from highest 3-year average yield and WUE to lowest,as follows:80%F+TS>60%F+TS>F+TS>F>TS>CK.Compared with the F+TS treatment,the 80%F+TS treatment increased yield by 9.9%and the WUE by 8.2%.Compared with CK,the 80%F+TS treatment increased yield by 46.9%and increased the WUE by 52.4%.Compared with the F+TS treatment,the 60%F+TS treatment increased yield by 2.6%and increased the WUE by 37.2%.Compared with CK,the 60%F+TS treatment increased yield by 3.7%and increased the WUE by 46.1%.Compared with all other treatments,the 80%F+TS and 60%F+TS treatments increased soil and plant analyzer development(SPAD)values and dry matter accumulation during the whole growth period of spring maize.The results of this study suggest that 60%-80%F+TS treatments are the optimal fertilization methods for spring maize crops cultivated in dryland areas on the Loess Plateau in eastern Gansu Province,China.