不同氮肥品种对高羊茅生长及养分吸收的影响

Effects of different nitrogen fertilizers on the growthand nutrient absorption characteristicsof Festuca arundinacea

摘要:

为明确不同氮肥对高羊茅(Festuca arundinacea)生长及养分吸收的影响,采用砂培试验,以无氮处理为对照,研究了硝酸铵、硝酸钙、尿素3种氮肥施肥条件下高羊茅的株高、地上和地下生物量、根系形态及养分吸收与分配特性。结果表明:与对照相比,施用氮肥可增加高羊茅植株株高和地上部干物质累积量,且氮、磷、钾各养分在地上部的累积数量和分配比例提高,单位根长的养分吸收量增加,植株根系长度降低。施用硝酸铵高羊茅植株具有较大的株高、干物质累积量、养分吸收量和根系长度,硝酸钙可显著提高植株地上部氮、钾浓度和地下部磷浓度,施用尿素高羊茅植株的根系直径和根表面积较大,地上部磷浓度和地下部氮、钾浓度较高。植株地上部养分分配比例3种氮肥间差异不显著,单位根长的养分吸收量硝酸铵>硝酸钙>尿素。综合分析植株生长及养分吸收状况,硝酸铵可作为首选氮源用于高羊茅的养护管理。

Abstract:

In order to clarify the effects of different nitrogen(N) fertilizers on the growth and nutrient absorptioncharacteristics of Festuca arundinacea,a sand culture test was employed and N-free treatment as a control,the plant height,aboveground and underground biomass,root morphology and nutrient absorption and distributioncharacteristics of F.arundinacea under the supply conditions of ammonium nitrate,calcium nitrateand urea were studied.The results showed that compared with the control,the application of N fertilizer couldincrease the plant height and the accumulation of dry matter aboveground in F.arundinacea,and the accumulativeamount and distribution ratio of N,phosphorus(P) and potassium(K) nutrient in the aboveground part increased,the same with the nutrient absorption per unit root length,while the total root length of plant decreased.Nitrogen fertilizers had significant effects on the growth and nutrient absorption of F.arundinacea.Amongthe three nitrogen fertilizer varieties,the application of ammonium nitrate could have a large plant height,dry matter accumulation,nutrient absorption and total root length.Calcium nitrate could significantly increasethe N and K concentration of aboveground and the P concentration of underground.The root diameter and rootsurface area were larger,P concentration aboveground andN,K concentrations underground of F.arundinaceawere higher with the application of urea than the other two fertilizers.There were no significant differences inthe distribution ratio of nutrients in the aboveground part among the three N fertilizers.Nutrient absorption perunit root length was ranked as ammonium nitrate > calcium nitrate > urea.From the comprehensive analysisof the plant growth and nutrient absorption ,ammonium nitrate can be used as the preferred nitrogen source forthe conservation and management of F.arundinacea.