摘要
基于田间小区试验,在常规施氮(U100,普通尿素,施氮量250kg/hm^(2))基础上,设置普通尿素、控释尿素减量20%(U80和C80)和40%处理(U60和C60),通过测定玉米产量及产量构成、氮素吸收和利用效率,结合土壤养分动态和植株光合特征与氮同化关键酶活性,评价控释尿素在玉米减氮增效中的作用。结果表明,氮肥减量20%时玉米产量和氮肥利用率都达到常规施氮水平,其中C80比U80增产14.5%;氮肥减量40%后产量有所降低,减产原因主要是百粒质量降低7.0%~9.5%。与U100相比,减氮20%的光合特征,土壤硝铵态氮水平,谷氨酸脱氢酶(NADH-GDH)、谷草转氨酶(GOT)和谷氨酰胺合成酶(GS)的活性均未显著下降,其中C80的净光合速率和光合氮利用效率比U100显著提高15.0%和24.8%,且C80较U80在提高氮素吸收总量、氮利用率、收获指数、光合氮利用率、酶活性和维持籽粒百粒质量方面更具优势。减氮40%后,U60的酶活性和光合特征与U100相比平均降低31.5%和27.6%,而C60的光合氮利用效率达到常规施氮水平。可见,氮肥减量20%时可以有效维持玉米产量,其中控释尿素一次性施用效果更佳,值得推广应用。
Reduced nitrogen(N)application rate is an important approach to realize the sustainable de-velopment of agriculture in China.Conventional N application(U100,common urea at a rate of 250kg/hm^(2)),common urea and controlled-release urea application with a N reduction of 20%(U80 andC80)and 40%(U60 and C60)were conducted respectively through a field plot experiment.Maizeyield,yield components,N uptake and N use efficiency(NUE)were detected;soil nutrient dynamics,photosynthetic characteristics and key enzyme activites for N assimilation were analyzed,and the roleof controlled-release urea in reducing N fertilizer application and increasing NUE was evaluated.Theresults showed that both the maize yield and NUE were equal to the treatment of U100 although re-duced 20%N application rate,and the maize yield increased by 14.5%in C80 compared to U80.Themaize yield decreased because the 100-grain mass was reduced by 7.0%-9.5%,after 40%N wasreduced.Compared with U100,reduced 20%N fertilizer did not result in lower photosynthetic charac-teristics,soil nitrate N,ammonium N,NADH-GDH,GOT and GS activities.In addition,the net pho-tosynthetic rate and photosynthetic NUE increased by 15.0%and 24.8%respectively under the treat-ment of C80 compared to U100.Compared to U80,C80 presented more advantages in improving total N uptake,NUE,harvest index,photosynthetic NUE,N assimilation enzyme activity,and maintaining100-grain mass.N assimilation enzyme activity and photosynthetic characteristics reduced by 31.5%and 27.6%,respectively under the treatment of U60 compared to U100,while the photosynthetic NUEof C60 still reached the same level under treatment of U100.It is concluded that maize yield can bemaintained when N fertilizer is reduced by 20%,and one-time application of controlled release urea ismore effective,which is worth being widely applied.
作者
杨清夏
龙光强
吴开贤
何澍然
李扬
赵平
YANG Qingxia;LONG Guangqiang;WU Kaixian;HE Shuran;LI Yang;ZHAO Ping(College of Resources and Environment Science,Yunnan Agricultural University,Kunming 650201.China;Yunnan Scientific Observation Station for Cultivated Land Conservation of the Ministry of Agriculture and Rural Affairs,Kunming 650201,China;College of Agronomy and Biotechnology,Yunnan Agricultural University,Kunming 650201,China)
出处
《西北农业学报》
CAS
CSCD
北大核心
2022年第1期34-43,共10页
Acta Agriculturae Boreali-occidentalis Sinica
基金
云南省重点研发计划(2018BB015)
云南省农业联合专项(2017FG001-027)
云南省中青年后备人才项目(2017HB027)。
关键词
控释尿素
玉米
产量
氮肥利用率
光合特征
氮同化酶
Controlled-release urea
Maize
Yield
Nitrogen use efficiency
Photosynthetic character-istics
N assimilation enzyme
