NaCl胁迫对大米草光合·蒸腾等生理特性的影响

研究了NaCl胁迫下大米草净光合速率(Pn)、蒸腾速率(Tr),叶片气孔导度(Gs)、细胞问CO_2浓度(Ci)、株高、叶长、叶宽、茎粗、叶绿素含量、气孔限制值和水分利用效率.结果表明:当NaCl浓度高于300mmol/L时,大米草Pn、Tr、Gs、株高、叶长以及叶绿素含量受到显著抑制(P＜0.05),叶宽及茎粗则无显著性差异.NaCl胁迫下,大米革光合速率的降低是气孔因素和非气孔因素综合导致的结果,Pn、Tr、Gs、株高以及叶绿素含量的降低可作为大米草受NaCl胁迫的症状,而WUE则保持在较高的水平,因此在防治大米草蔓延时,排水处理不是最佳选择.

Effects of NaCl stress on photosynthesis·transpiration and other physiological characteristics of Spartina anglica

The effects of NaCl stress on some physiological characteristics of Spartina anglica were studied. These characteristics are photosynthetic rate(Pn) , transpiration rate(Tr) , stomatal conductance (Gs) , carbon dioxide between cells (Ci) , relative chlorophyll content, Ls, water use efficiency( WUE) including it's height, leaf length, leaf width and diameter. The results indicated that characteristics like Pn, Tr, Gs, height, leaf length and chlorophyll content were inhibited seriously(P <0. 05) when NaCl concentration was higher than 300mmol/L However, leaf width and diameter was no significant difference. Under NaCl stress, the primary reason of the decrease of photosynthetic rate was stomatal and non-stomatal limitation. Reduction of Pn, Tr, Gs, height, leaf length and Chl contents could take as NaCl stress symptoms. At the same time, WUE kept on a relative high level, so drainage was not the best way to prohibit the spread of S. anglica.