不同氮素形态培养对枳橙幼苗硝酸还原酶活性及相关基因表达的影响  

Effect of different forms of nitrogen on the activity of nitrate reductase and expression of the relative genes in Citrus sinensis × Poncirus trifoliate

作　　者：孙敏红[1,2] 卢晓鹏[1] 曹雄军[1] 李静[1] 熊江[1] 谢深喜[1] SUN Minhong LU Xiaopeng CAO Xiongjun LI Jing XIONG Jiang XIE Shenxi(Horticulture and Landscape College, Hunan Agricultural University, Changsha 410128, Hunan, China Forestry College, Central South University of Forestry ＆ Technology, Changsha 410004, Huaan, China)

机构地区：[1]湖南农业大学园艺园林学院,长沙410128 [2]中南林业科技大学林学院,长沙410004

出　　处：《果树学报》2017年第4期410-417,共8页Journal of Fruit Science

基　　金：现代农业(柑橘)产业技术体系(CARS-027);国家自然科学基金(31401824);教育部高校博士点基金(20134320120006)

摘　　要：【目的】进一步探讨枳橙对氮素吸收利用机制,为柑橘生产上提高氮素利用效率和科学施肥提供科学依据。【方法】以枳橙为材料,采用水培方法,在Hoagland配方的基础上进行调节,研究了不同形态氮素配比对枳橙幼苗硝酸还原酶(NR)活性变化及相关基因表达量的影响。【结果】幼苗叶片及根系NR活性均随着培养时间的延长而增加,且叶片NR活性高于根系。其中2号(NO_3^-∶NH_4^+=7∶3)和3号(NO_3^-∶NH_4^+=5∶5)处理的叶片酶活最高;1号(NO_3^-∶NH_4^+=10∶0)和2号(NO_3^-∶NH_4^+=7∶3)处理根系的NR活性显著高于其他处理;进一步研究NR相关基因表达情况表明:3个基因(CitNia1、CitNia2、CitNia OA)在不同处理的枳橙幼苗体内均有表达,其中CitNia1和CitNia2分别是根系和叶片NR相关主效基因,2者均受到NO_3^-、NH_4^+配比诱导,且3号处理(NO_3^-∶NH_4^+=5∶5)下表达量最高。【结论】枳橙幼苗硝态氮代谢的主要部位为叶片,且CitNia2是主效基因,通过调节铵硝比例可以促进其表达。[ Objective ] Citrus is one of the main fruit trees in the world, and China is the biggest country in its production. There are a number of factors affectting growth and fruitting of Citrus. The nutrition defi- ciency can cause physiological disorder. Nitrogen is the most important element for Citrus. At present, seedling rootstocks are used for citrus production in China. The ability of absorption and transportation of inorganic nutrients varies with the species of rootstocks. Thus, it is necessary to investigate the ability of nitrogen absorption of the main rootstock. Citrus sinensis （L.） OsbeckxPoncirus trifoliate （L.） Raf. is a hy- brid of trifoliate and sweet orange being widely used due to its anti-aging disease characteristic. NO3^- and NH4^＋ are the two main forms of inorganic nitrogen used. The influence of the forms of nitrogen and the ra- tio of NO3^- and NH4^＋ on C. sinensis （L.） OsbeckxP. trifoliate （L.） Raf. and the nitrogen metabolism mechanism remains unknown at present. Nitrate reductase （NR） plays an important role in the metabolism pro- cess of nitrogen. Therefore, this research aims to study the nitrate absorption ability and mechanism in C. sinensis （L.） Osbeck × P. trifoliate （L.） Raf. to provide a scientific basis for improving efficiency of nitro- gen usage in citrus production. [Methods]C. sinensis （L.） Osbeck × P. trifoliate （L.） Raf., were planted by hy- droponic method with Hoagland nutrient solution. Five treatments were made as follows： No. 1 （NO3^- ： NH4^＋=10 ： 0）, No.2 （NO3^- ： NH4^＋=7 ： 3 ）, No.3 （NO3^- ： NH4^＋=5 ： 5 ）, No.4 （NO3^- ： NH4^＋=3 ： 7） and No.5 （NO3^- ： NH4^＋=0 ： 10）. The seedlings were planted in environmental chamber, and the culture medium for each treatment was added 7 μmol. L^-1 C2H4N4 in the nutrient solution to inhibit nitrate. The pH value of media was 6 or so, ventilation time was 15 min every 3 h. The seedlings were cultured for different times （0, 20, 40, 60, 80

关 键 词：枳橙 硝态氮 铵态氮 硝酸还原酶 

分 类 号：S666.4[农业科学—果树学]