氮素水平和形态对小麦幼苗叶最小导度的影响  

Effect of nitrogen concentration and form on leaf minimum conductance of winter wheat seedlings

作　　者：左力翔[1,2] 赵丽敏[1,2] 李秧秧[2,3] 李俊辉[3] 

机构地区：[1]西北农林科技大学资源环境学院,陕西杨凌712100 [2]西北农林科技大学黄土高原土壤侵蚀与旱地农业国家重点实验室,陕西杨凌712100 [3]中国科学院水利部水土保持研究所,陕西杨凌712100

出　　处：《干旱地区农业研究》2012年第5期82-87,共6页Agricultural Research in the Arid Areas

摘　　要：叶最小导度反映了叶片气孔关闭后残余蒸腾的大小,因而是植物抗旱性的一个重要方面。采用水培试验,研究了不同氮素浓度(低氮:2 mmol/L;高氮:15 mmol/L)和形态(硝态氮、铵态氮和硝酸铵)对小麦叶最小导度的影响,试图揭示氮素营养影响植物抗旱性的生理机制。结果表明:铵态氮和硝态氮处理高氮的叶最小导度低于低氮,但硝酸铵处理两个氮水平下的叶最小导度无差异;氮素形态对叶最小导度无显著影响。氮浓度对与叶最小导度有关的形态和生理特征无影响,氮素形态对比叶片重、绒毛密度、蜡质含量和蜡质晶体形态结构和气孔特性亦无显著影响,对叶含水量有显著影响,铵态氮处理叶含水量低于硝态氮和硝酸铵处理。相关分析表明,叶最小导度与比叶片重呈显著正相关。本研究结果说明比叶片重的差异是导致不同处理最小导度不同的重要原因,氮素形态并未通过影响叶最小导度而对植物的抗旱性产生影响。Leaf minimum conductance （gml.） reflects leaf residual transpiration after stomatal closure, thus it is one important aspect of plant drought resistance. The effect of nitrogen concentration and form on groin is studied in this re search aimed to elucidate related physiological mechanism of nitrogen nutrition on plant drought resistance. The results indicated that gmin of high nitrogen concentration （15 mmol/L） was lower than that of low nitrogen concentration （2 mmol/L） for nitrate and ammonium treatments but no difference of gmin existed between two nitrogen levels for ammoni- um nitrate treatment. Nitrogen form had no effect on groin. Nitrogen concentration had no effect on the morphological and physiological traits related with groin, nitrogen form also had no effect on specific leaf weight, tricome density, wax load and crystal structure and stomatal traits, but it had significant effect on leaf water content, ammonium treatments had lower water content than the other two treatments. Pearson correlation analysis indicated gmin was significantly and posi tively related with specific leaf weight, suggesting the difference of gmin is caused by specifc leaf weight in this study, nitrogen form did not affect plant drought resistance through change of groin.

关 键 词：叶最小导度 氮素浓度和形态 小麦幼苗 

分 类 号：Q945.78[生物学—植物学] S131[农业科学—农业基础科学]