摘要
为了探明缺氮及不同氮素形态对烟草幼苗糖代谢的影响机理。该试验以‘中烟100’为试材,设置正常供氮为对照(CK,NO3-∶NH4+=1∶1)、缺氮(T1)、单一铵态氮(T2)和单一硝态氮(T3)4个处理的沙培试验,检测烟株功能叶片的全氮、还原糖、总糖、蔗糖淀粉的含量及糖代谢相关酶的活性,并分析根、茎、叶等3个部位糖代谢关键基因(SUT1、INV、GBSSI、AGPase)的表达差异。结果显示:(1)烟株功能叶片的全氮含量表现为T3>CK>T2>T1。(2)与CK前期相比,T1处理显著增加了烟株叶片的还原糖、总糖、蔗糖及淀粉含量,降低了淀粉酶的活性,但对转化酶活性影响不显著;其中烟株叶片淀粉积累表现为T1>T2>CK>T3。(3)缺氮及氮素形态对糖转运蛋白基因(SUT1)、焦磷酸化酶基因(AGPase)和颗粒淀粉合成酶基因(GBSSI)等关键基因的表达影响显著。研究认为,缺氮及不同氮素形态下烟草幼苗氮素利用率与淀粉积累成反比,其中蔗糖转运蛋白基因(SUT1)在氮素形态影响烟叶糖代谢过程中起关键作用。
In order to demonstrate the mechanism of nitrogen stress and different nitrogen torms on glucose metabolism of tobacco seedlings,we used ‘Zhongyan 100＇ as the material. Sand culture were adopted in the normal supply of nitrogen （CK,NO3^- ： NH4^＋ = 1 ： 1）, nitrogen deficiency （T1）, single ammonium （T2） and single nitrate （T3） of the four treatments. The contents of reducing sugar,total sugars, sucrose, starch and the activities of glucose metabolism-related enzymes in functional leaves of tobacco plants were detec- ted. Meanwhile,we analyzed the differences of key glucose metabolism genes （SUT1, INV,GBSSI,AG- Pase） in roots, stems, leaves. The results showed that ： （1） The total N in four treatments are T3〉CK〉T2〉T1. （2）The contents of sugar,total sugar,sucrose and starch in tobacco leaves of T1 were increased sig- nificantly （P〈0.05） compared with CK during early plant development;The amylase activity was signifi- cantly reduced,however the invertase activity was different （P〉0.05）. The accumulation of starch in four treatments are T1〉T2〉CK〉T2. （3）The glucose metabolism gene expression showed that SUT1, INV, AGPase,GBSSI were expressed significantly in T1 ,T2 and Ta ,indicating that biosynthesis of grain starch in T1 ,T2 and T3 were more active. Altogether,our data suggest that the accumulation of starch and nitro- gen utilization rate are inversely proportional,and the SUT1 gene may be very important in starch biosyn-thesis under different nitrogen forms.
出处
《西北植物学报》
CAS
CSCD
北大核心
2014年第3期530-535,共6页
Acta Botanica Boreali-Occidentalia Sinica
基金
中国烟草总公司特色优质烟叶开发重大专项浓香型项目(Ts-01)
关键词
烟草
氮素形态
糖代谢
基因表达
tobacco
nitrogen forms
glucose metabolism
gene expression
