前氮后移对寒地水稻根系吸收能力的影响  

Effects of N Application at Later Stage on Absorbability of Rice Root in Cold Area

作　　者：郁燕[1] 彭显龙[1] 刘元英[1] 张慧[1] 陈丽楠[1] 

机构地区：[1]东北农业大学资源与环境学院,哈尔滨150030

出　　处：《土壤》2011年第4期548-553,共6页Soils

基　　金：公益性行业科研专项(200803030);东北农业大学创新团队项目资助

摘　　要：采用田间小区试验方法，在高氮（135kg／hm2）和中氮（105kg／hm2）水平下，研究了穗肥比例对寒地水稻根系吸收能力的影响。试验结果表明：高氮水平下，穗肥比例为15％的处理各个时期伤流量和根系含糖量均最低，中氮水平下祧肥比例为35％的处理伤流量和根系含糖量均最高。相同氮量条件下，随着穗肥比例增加根系伤流量增加，幼秘分化期增加均达到了5％的显著水平；中氮条件下，前氮后移使幼穗分化期和抽穗后20天的根系含糖量显著提高了14．0％和35．1％（p〈0．05）。穗肥比例由15％增加到35％，水稻吸氮量增加了11．1％～15．6％，氮肥吸收利用率提高了20％～43％，农学利用率提高了37．5％～38．5％，氮肥偏生产力提高了12．6％～20．8％，水稻产量提高了12.3％～12．7％．且均达到了5％的显著水平。以上结果表明，前氮后移促进了水稻碳氦代谢的协调．增加了根系可溶性糖含量，提高了水稻根系吸氮能力，增加了氮素积累量，因此提高了氮肥利用率和产量。A plot experiment with different N rates （135 kg/hm2 and 105 kg/hm2） was designed to study the effects of panicle N fertilizer ratio on absorbability of rice root in cold area. The results showed that the root bleeding and soluble sugar content of root in the 15% panicle N under high N level （135 kg/hm2） was lower and in the treatment of 35% under middle N level （105 kg/hm2） was higher at each period. Under the same N level, compared with 15% panicle fertilizer, the root bleeding of 35% panicle fertilizer were significantly increased at panicle initiation. At the same time, the soluble sugar content of rice root at panicle initiation stage and 20 days after heading were improved by 14.0% and 35.1% （p〈0.05） respectively, Compared with 15% panicle fertilizer treatment, 35% panicle fertilizer treatment significantly increased total N uptake rate, N recovery efficiency, agronomic efficiency and partial factor productivity by 11.1% - 15.6%, 20% - 43%, 37.5% - 38.5% and 12.6% - 20.8% （p〈0.05）, respectively, and increased average yield by 12.3% - 12.7% （p〈0.05） as well. The results suggested that the increase of soluble sugar rate of rice root and root bleeding improved N uptake and N use efficiency by improving the concert of riee root C and N metabolism.

关 键 词：水稻 伤流量 可溶性糖 氮素吸收 氮肥利用率 

分 类 号：S158.3[农业科学—土壤学]