施氮量对晋南旱地冬小麦光合特性、产量及氮素利用的影响  

Effects of Nitrogen Application Rate on Photosynthetic Characteristics,Yield,and Nitrogen Utilization in Rainfed Winter Wheat in Southern Shanxi

作　　者：李廷亮[1] 谢英荷[1] 洪坚平[1] 冯倩[1] 孙丞鸿 王志伟 

机构地区：[1]山西农业大学资源环境学院,山西太谷030801 [2]宁波市鄞州区姜山镇农技站,浙江宁波315191 [3]太原市农产品质量安全监测中心,山西太原030000

出　　处：《作物学报》2013年第4期704-711,共8页Acta Agronomica Sinica

基　　金：国家公益性行业(农业)科研专项经费项目(201303104);国家现代农业产业技术体系建设专项;山西农业大学科技创新基金项目(201231);山西农业大学引进人才科研启动费(XB2011007)资助

摘　　要：在自然降水条件下,通过2年大田试验研究了施氮量对晋南旱地冬小麦光合特性、产量、氮素利用效率以及0～200cm土层NO3-N残留的影响。结果表明,在0～270kghm-2施氮量范围内,随施氮量的增加,旗叶的净光合速率和叶绿素含量增加,气孔导度增大,胞间二氧化碳浓度降低,旗叶蒸腾速率显著提高;但施氮量超过180kghm-2时,除蒸腾速率外其他光合指标均无显著变化。N180处理的氮素当季回收率及氮素农学效率均最高,且显著高于N90处理。生物产量以N270处理最高,且与其他处理差异显著;但施氮量超过180kghm-2时,氮素营养对籽粒产量不再有显著贡献。从产量构成因素来看,提高穗数和穗粒数是增加当地旱作小麦籽粒产量的关键。施氮量90～270kghm-2会造成土壤NO3-N的残留,残留量占施氮量的35%左右,其中20～40cm和40～60cm土层出现NO3-N积累峰值,NO3-N残留会导致氮素淋失风险增加及产量对氮肥反应不明显。综合考虑光合特性、产量、氮素利用率和NO3-N残留量,当地旱作冬小麦施氮量以180kghm-2左右为宜。The objective of this study was to optimize the application rate of nitrogen （N） fertilizer in winter wheat production in the rainfed area of southern Shanxi Province, China. In a two-year field experiment from October 2008 to June 2010, we tested the effects of N application rate on photosynthetic characteristics, grain yield and its components, and N use efficiency of wheat cultivar ＂Linhan 6＂ and the soil residual nitrate-nitrogen （NO3-N） in 0-200 cm soil profile after harvest under four treatments of N application （N rates of 0, 90, 180, and 270 kg ha-l）. In the N application range tested, the chlorophyll content, net photosynthetic rate （Pa）, stomatal conductance （Gs）, and transpiration rate （Tr） of flag leaf were enhanced, and intercellular CO2 concentration （Ci） was declined with increasing N mount. When N application level was higher than 180 kg ha1, no significant changes in these photosynthetic indices, except for Tr, were observed. The values of N absorption in grain, seasonal N recovery efficiency, and N agronomic efficiency in N180 treatment were the highest, which were significantly higher than those in N90 treatment. The biomass of N270 was the highest among the treatments, which was significantly different from that of other treatments; however, the treatments with N rate higher than 180 kg ha-1 had no significant contributions to grain yield. In local wheat production, spike number and grain number per spike are the major restraints of wheat yield. Nitrogen application rates from 90 to 270 kg ha-1 resulted in NO3-N residues in 0-200 cm soil layers, with the residue rate as high as 35% of the total N application amounts, particularly in 20-40 and 40-60 cm soil layers, which caused a risk of increasing N leaching and the insensitive response of yield to N application. Therefore, in a comprehensive consideration of grain yield, N use efficiency, and NO3-N residue in soil, we propose the optimal N application rate of 180 kg ha-1 in rainfed winter wheat growing in south

关 键 词：冬小麦 施氮量 旱地 光合特性 产量 氮素利用 

分 类 号：S512.1[农业科学—作物学]