减量施氮对玉米-大豆套作体系中大豆根瘤固氮及氮素吸收利用的影响  

Effect of Reduced N Application on Nodule N Fixation,N Uptake and Utilization of Soybean in Maize-Soybean Relay Strip Intercropping System

作　　者：刘文钰[1] 雍太文[1] 刘小明[1] 陈鹏[1] 董茜[1] 徐婷[1] 杨文钰[1] 

机构地区：[1]四川农业大学农学院/农业部西南作物生理生态与耕作重点实验室,四川成都611130

出　　处：《大豆科学》2014年第5期705-712,共8页Soybean Science

基　　金：现代产业技术体系建设专项(CARS-04-PS19);国家自然科学基金(31271669;31201169)

摘　　要：通过田间试验,研究了种植模式(大豆单作、玉米-大豆套作)和施氮水平(0,180,240 kg·hm-2)对大豆根瘤固氮特性和氮素吸收利用的影响。结果表明:随生育时期的推移,大豆的单株根瘤数、根瘤干重在单作模式下呈先增加再降低的趋势,而套作模式下则呈持续增加的趋势,在R5期最高;单株根瘤固氮潜力在两种种植模式下均呈先增加再降低的趋势,在R2期最高。与单作比较,套作大豆的单株根瘤数、根瘤干重、根瘤固氮潜力和总吸氮量在V5、R2期降低,在R5期则提高,氮素收获指数、氮肥农学利用率和吸收利用率显著提高。适量施氮有利于提高大豆的根瘤固氮能力,增加植株对氮素的吸收利用。套作模式下,减量施氮处理R5期的单株根瘤数、根瘤干重、根瘤固氮潜力及R8期的总吸氮量比不施氮处理高26.9%、15.5%、14.3%和58.2%,比习惯施氮处理高19.7%、12.0%、23.1%和11.3%,氮肥农学利用率和吸收利用率比习惯施氮处理高73.5%和20.1%。玉米-大豆套作减量一体化施肥促进了大豆根瘤固氮,提高了套作大豆和整个玉米-大豆套作系统的氮肥吸收利用效率。To investigate the effects of cropping patterns and N application rates on nodule N fixation characteristics,N uptake and utilization of soybean,a field experiment was conducted with three N application rates（0,180,240 kg·hm^-2）representing zero,reduced and conventional N application,respectively）and two planting patterns（soybean monoculture and maize-soybean relay strip intercropping）. The results showed that,with the development of soybean growth stages,soybean nodules number,nodules dry weight per plant increased first and decreased afterwards in monoculture,but kept increasing in relay strip intercropping system,and got the highest value at R5 stage;Nodule N fixation potential per plant in both monoculture and relay strip intercropping system increased first and decreased afterwards,and got the highest value at R2 stage. Compared to monoculture soybean,nodules number,nodules dry weight,nodule N fixation potential per plant and total N uptake of intercropping soybean decreased at R2 stage,but increased at R5 stage,besides,N harvest index,N agromomy efficiency（AEN）,and N uptake efficiency（UEN）of intercropping soybean increased significantly. Reduced N application was beneficial to improve the ability of soybean nodule N fixation,N uptake and utilization. In the reduced N application treatment,nodules number,nodules dry weight,nodule N fixation potential per plant at R5 stage and total N uptake at R8 stage of relay intercropping soybean increased by 26. 9%,15. 5%,14. 3% and 58. 3%,respectively,compared with the zero N application treatment,and increased by19. 7%,12. 0%,23. 1% and 11. 3% respectively compared with the conventional N application treatment,furthermore,AEN and UENwere 73. 5% and 20. 1% higher than the conventional N application treatment. The reduced N application in maizesoybean relay strip intercropping system promoted nodule N fixation,improved N uptake and utilization efficiency of intercropping soybean and the whole maize-soybean relay strip intercropping system.

关 键 词：减量施氮 根瘤固氮 氮素吸收 大豆 玉米-大豆套作 

分 类 号：S565.1[农业科学—作物学]