干旱胁迫对乌桕幼苗光合色素及光合性能的影响  

Effect of Drought Stress on Photosynthetic Pigment and Photosynthesis of Sapium sebiferum Seedlings

作　　者：金雅琴[1] 张丽娟[1] 李冬林[2] 王磊[2] 

机构地区：[1]金陵科技学院园艺学院,江苏南京200038 [2]江苏省林业科学研究院,江苏南京211153

出　　处：《江西农业大学学报》2011年第4期731-737,共7页Acta Agriculturae Universitatis Jiangxiensis

基　　金：江苏省自然科学基金资助项目(BK2010094);国家林业局林业公益性行业科研专项(201004091)

摘　　要：应用控水试验研究干旱胁迫对乌桕1年生幼苗光合色素及光合性能的影响。结果表明,种源GC2、SC4、HS1、XN1叶绿素含量变化基本一致,在整个干旱期尽管存在一定起伏,但差异不显著(P>0.05),说明干旱对4种源幼苗叶绿素含量的影响不明显;种源GC2、SC4、HS1、XN1类胡萝卜素含量在干旱后期均有一定程度升高,且含量变化达显著水平(P<0.05),说明干旱对幼苗类胡萝卜素的合成具有促进作用;HZ2断水后叶绿素与类胡萝卜素含量迅速下降,复水含量回升。干旱胁迫下,乌桕幼苗净光合速率(Pn)普遍下降,气孔导度(Gs)也呈下降趋势。相关分析表明,Pn与Gs、Tr呈极显著正相关(P<0.01),相关系数(R)分别为0.642、0.728,与光合色素指标的相关性不显著(P>0.05)。在干旱胁迫下,乌桕幼苗光合作用强度下降可能源于叶片气孔的关闭以及细胞间隙CO2浓度降低,而与光合色素的含量变化无直接相关。Effect of drought stress on photosynthetic pigment and photosynthesis of Sapium sebiferum Seedlings was studied by water control experiment.The results showed that the changes in chlorophyll a,chlorophyll b,and chlorophyll（a＋b） contents of S.sebiferum seedings from GC2,SC4,HS1 and XN1 provenances were consistent with drought time extended,and the changes were not significant（p0.05）during the drought period.Meanwhile the carotenoid increased significantly（p0.05）,this illuminated that drought stress accelerated the synthesis of the carotenoid.The contents of both chlorophyll,and carotenoid from HZ2 provenances droped rapidly under drought stress,but reversed afterwatering.Net photosynthetic rate（Pn） and the stomatal conductance（Gs）of seedings showed the tendency of decreasing under drought stress.Correlation analysis showed that Pn was significantly positively correlated to Gs and Tr（p0.01）,the correlation coefficients（R） were 0.642,0.728,respectively.Correlation was not significant between Pn and photosynthetic pigment（p0.05）,so the decline of Pn could be due to the stomatal restriction and the decrease of intercellular CO2 concentration（Ci）,and did not result from the decline of photosynthetic pigment content.

关 键 词：乌桕 干旱胁迫 光合色素 光合作用 

分 类 号：Q948.112[生物学—植物学] S718.43[农业科学—林学]