施氮对不同抗旱性小麦叶片光合及生长特性的影响  

Effects of application nitrogen on photosynthesis and growth of different drought resistance winter wheat cultivars

作　　者：张绪成[1] 上官周平[1] 

机构地区：[1]中国科学院水土保持研究所黄土高原土壤侵蚀与旱地农业国家重点实验室

出　　处：《中国生态农业学报》2007年第6期59-64,共6页Chinese Journal of Eco-Agriculture

基　　金：中国科学院重要方向项目(KSCX2-YW-N-003);中国科学院西部之光人才培养项目资助

摘　　要：在大田试验条件下,对2个不同抗旱特性的小麦品种在5个N素营养水平下各生育时期叶片光合速率（Pn）、气孔导度（Gs）、气孔限制值（Ls）等气体交换参数以及地上生物量进行了测定。结果表明,两个小麦品种的叶片Pn随生育进程呈逐渐递减趋势,对照在拔节期出现Pn峰值,N素各处理Pn的峰值均出现在分蘖期。不同N素处理的两个小麦品种的Gs、Ls峰值均出现在拔节期~抽穗期,依生育进程呈先升后降的变化趋势。适量N素提高了叶片Pn和Gs,降低了Ls。不同抗旱性小麦光合参数的差异因生育期不同而有差别,N180处理旱地品种较水地品种有高的Pn和Gs,在拔节期～抽穗期旱地品种的Pn、Gs均高于水地品种。小麦地上单株干重随生育进程持续增加。N素对地上单株生物量的影响因抗旱性差异而不同,旱地品种的地上单株生物量随施N量的增加而表现先降低后升高的变化趋势,水地品种则表现出持续下降的趋势;两个品种的籽粒产量随N素水平提高呈先升高后下降趋势,在N180处理达到最高。因此,N180处理是旱地小麦最为适宜的施N水平。结合光合、生长及叶片水势变化特性,认为适量N素可提高干旱环境下叶片光合机构的适应能力,说明N素对提高小麦抗旱能力有积极意义。The net photosynthetic rate（Pn）,stomatal conductance（Gs）,stomatal limited value（Ls） and aboveground biomass is at different growth stages of two contrasted drought-resistance cultivars of winter wheat treated by five nitrogen levels were investigated in field experiment.The results show that the net photosynthetic rate decreases as the plant growth,the highest Pn of the CK（no N fertilization） is on the jointing stage and those of other treatments（N fertilization） are on the tillering stage.The highest Gs and Ls of all N treatments are on the jointing stage to heading stage.They first increase and decrease finally as plant growing.Reasonable nitrogen supply can increase Pn and Gs and decrease Ls.The Pn and Gs of different cultivars are different with growth stages and nitrogen fertilizations,the Pn and Gs of dryland cultivar are higher than those of watered cultivar at the N180 treatment,and those of the dryland cultivar are higher than those of watered cultivar from the jointing stage to heading stage.The aboveground biomass increases continuously as the plant growing.The effect of nitrogen supply on the aboveground biomass is different between cultivars,which of dryland cultivar increases firstly and decreases finally as the nitrogen supply increase,and which of the watered cultivar decreases continuously.The grain yield of the two cultivars increases firstly and decreases finally with the nitrogen fertilization increase,the highest grain yield of two cultivars is on N180 treatment,so the N180 treatment is the optimize nitrogen supply level in field.

关 键 词：小麦 N素营养 光合特性 生物量 籽粒产量 叶片水势 抗旱性 

分 类 号：S661.1[农业科学—果树学]