不同氮素添加水平对紫花苜蓿生长性能的影响  

Effects of Different Nitrogen Application Levels on Alfalfa Growth

作　　者：万里强[1] 王丹[1] 何锋[1] 吕会刚[1] 谢开云[1] 李向林[1] 王栋[1] 秦燕[1] 

机构地区：[1]中国农业科学院北京畜牧兽医研究所,北京100193

出　　处：《西南农业学报》2014年第3期1175-1180,共6页Southwest China Journal of Agricultural Sciences

基　　金：基本科研业务费项目(2013ywf-yb-1);国家自然科学基金项目(31372370)

摘　　要：氮素添加对于紫花苜蓿生长具有重要作用。本试验研究了不同氮素添加水平对于紫花苜蓿生长性能各个指标的影响机制。结果表明,施氮对不同茬次苜蓿的株高、茎粗影响效果不明显,而对苜蓿的分枝数影响效果显著。每一茬次的苜蓿分枝数都随施氮量的增加而增加,并且处理之间差异显著(P<0.05);苜蓿单株地上生物量随施氮量的增加而增加,但从第1茬到第4茬,增加的趋势逐渐平缓。施氮对第1茬、第2茬和第4茬的苜蓿单株生物量有显著影响(P<0.05),而对第3茬苜蓿单株生物量影响不显著;随着施氮量的增加,紫花苜蓿根系的总表面积、总体积、根颈粗和交叉数呈逐渐增加的趋势,而紫花苜蓿的总根长、平均直径和分叉数随施氮量的增加并未呈现逐渐增加的趋势,而是先增加后降低,N60处理的紫花苜蓿总根长、平均直径和分叉数最大。Nitrogen addition is rather important for the growth of alfalfa.The experiment was conducted to study the effects of different nitrogen applications on the growth index of alfalfa.The results showed that the effects of nitrogen application on plant height and stem diameter of alfalfa was not obvious,but nitrogen fertilization had significant influence on alfalfa branches.Alfalfa branches increased with increasing the amount of nitrogen application in each cut and the difference among treatments was extremely significant（P 〈 0.05）.Alfalfa biomass per plant increased with increasing the amount of nitrogen fertilizer,but the trend increased gently from the first cut to the fourth cut.Nitrogen fertilization had the significant effect on the alfalfa biomass of the first cut,second cut and fourth cut,while nitrogen fertilization had no significant effect on the alfalfa biomass of the third cut.With the increase of the amount of nitrogen fertilizer,alfalfa total surface area,total volume,root collar and crossings increased gradually,while the total root length,the average diameter and bifurcations did not increased gradually,but the first increase and then decrease,alfalfa total root length,average diameter and bifurcations were maximum in the treatment of N60.

关 键 词：氮素添加 紫花苜蓿 生长性状 生物量 根系 

分 类 号：S551.7[农业科学—作物学]