供氮形态与部位对局部根区水分胁迫下玉米水分吸收与利用的影响  

Water Uptake and Utilization of Maize under Partial Rootzone Water Stress with Different Nitrogen Forms and Application Positions

作　　者：周秀杰[1] 王海红[1] 束良佐[1] 祝鹏飞[1] 周伟[1] 闫凯[1] 

机构地区：[1]淮北师范大学生命科学学院,资源植物生物学安徽省重点实验室,安徽淮北235000

出　　处：《西北植物学报》2010年第7期1426-1434,共9页Acta Botanica Boreali-Occidentalia Sinica

基　　金：国家自然科学基金项目(30771286);资源植物生物学安徽省重点实验室项目(KLPRB200905)资助

摘　　要：试验以玉米品种金海五号幼苗为材料,在分根条件下采用聚乙二醇(PEG-6000)模拟局部根区水分胁迫,设置3种供氮形态(硝态氮、铵态氮、两者各占50%的混合氮)和2种供氮部位(水氮同区,氮加入到无PEG侧;水氮异区,氮加入到含PEG侧),研究局部根区水分胁迫下氮形态与供应部位对玉米水分吸收和利用的调节与作用机制,为局部根区灌溉水分高效利用提供理论依据.结果发现:(1)同一氮形态下水氮同区供应的植株蒸腾速率、耗水量、木质部汁液流速和生物量较高,加有硝态氮源处理无PEG侧根系的导管数目及单一氮形态处理无PEG侧根系的导管直径较高,但木质部汁液、叶片中脱落酸(ABA)浓度以及水分利用效率均较低.(2)同一供氮部位下,植株的蒸腾速率、耗水量、木质部汁液流速和生物量的顺序均为混合氮>硝态氮>铵态氮依次,但单一铵态氮处理植株的ABA浓度较高,水分利用效率较高.研究表明,同一氮形态下水氮同区供应植株生长较好、水分吸收能力较强,但水氮异区供应下植株的水分利用效率较高;同一供氮部位下,植株生长和水分吸收能力的顺序为混合氮>硝态氮>铵态氮,但单供铵态氮植株的水分利用效率较高.To provide theoretical basis for improving water use efficiency,effects of nitrogen forms and its application positions on water uptake and utilization of maize under partial root-zone water stress were studied.Maize seedlings （Jinhai No.5） were employed as plant meterial.A split-root system composed of two root compartments was used.Polyethylene glycol （PEG 6000） was added to only one root compartment simulating partial root-zone water stress.Nitrogen was set as three forms （ammonium nitrogen;nitrate nitrogen;mixed nitrogen of ammonium and nitrate at the ratio of 1：（1）Nitrogen was supplied just to water-stressed-compartment or non-water-stressed-compartment,to form two application positions.The results showed that,compared to nitrogen supplied to water stressed compartment,nitrogen supplied to non-water-stressed compartment improved plant transpiration rate,total water consumption,xylem sap flow rate and plant biomass.Number of vessel of non-PEG added side root with nitrate nitrogen supplied and vessel diameter of non-PEG added side root with sole nitrogen source supplied were higher.But ABA concentration of leaf and xylem sap,water use efficiency was increased when nitrogen was supplied to water-stressed compartment.Plant transpiration rate,total water consumption,xylem sap flow rate and plant biomass decreased at the following tendency as mixed nitrogen source,nitrate nitrogen,ammonium nitrogen when nitrogen was supplied to the same position.However,ammonium nutrition had a greater effect on the increment in ABA concentration and water use efficiency of plant compared to other nitrogen sources.The results indicated that,plant grew better and water uptake capacity was improved when nitrogen was supplied to non-water-stressed compartment,but water use efficiency improved by nitrogen supplied to water-stressed compartment.However,when nitrogen was supplied to the same position,plant growth and water uptake decreased at the following tendency as mixed nitrogen source,nitrate nitrogen,ammonium nitro

关 键 词：氮形态 供氮部位 局部根区水分胁迫 玉米 水分吸收能力 水分利用效率 

分 类 号：Q945.78[生物学—植物学]