不同光照条件下花榈木幼苗的生理生化响应及生长效应  

Physiological and biochemical responses and growth effects of Ormosia henryi seedlings under different light conditions

作　　者：段如雁[1] 韦小丽[1] 孟宪帅[1] 

机构地区：[1]贵州大学林学院,贵州贵阳550025

出　　处：《中南林业科技大学学报》2013年第5期30-34,共5页Journal of Central South University of Forestry & Technology

基　　金：贵州省林业厅项目(黔林科合[2010]重大02号);贵州省国际合作项目(黔科合外G字[2012]7012号);贵州省省长基金(黔省专合字(2009)01号)

摘　　要：为探讨花榈木幼苗对光照环境的生态适应性,采用人工模拟不同的光照条件(100%全光照、75%光照、50%光照、25%光照)进行盆栽试验,测定了不同光照条件下花榈木幼苗生理生化和生长指标。结果表明:随着遮光程度的增加,幼苗净光合速率、蒸腾速率有减小的趋势;强度遮光(全光照的50%和25%)使幼苗的光合日变化曲线由双峰型变成单峰型,没有午休现象;其水分利用效率和光能利用率大小排序为75%光照>50%光照>100%光照>25%光照;随着光照强度的减弱,幼苗叶绿素a、叶绿素b、叶绿素总量和SOD活性都逐渐增加,而可溶性糖含量总体上则呈降低趋势,丙二醛含量则表现为弱光下和强光下较大;苗高生长量、地径生长量、生物量最大的是75%光照处理,不同光照强度下花榈木幼苗的根冠比差异不显著,但有随着光照减弱而降低的趋势。对花榈木幼苗生理生化和生长发育有利的光照强度是全光照的75%左右,因此,花榈木幼苗培育中应适当遮荫。In order to study the ecological adaptability of Ormosia henryi seedlings to photoenvironment,by artificially simulating different light conditions(100% full light;75%,50% and 25% of full light),a pot experiment was conducted,the physiological and growth indexes were determined of Ormosia henryi seedling.The results show that with the increasing of shading intension,the photosynthetic rate and transpiration rate of seedlings decreased;the strong shading(50% and 25% full light) made the diurnal variation curve of photosynthetic rate from bimodal curve to single-peak curve,without 'midday depression';the order of water use efficiency and light energy utilization rate were: 75% > 50% > 100% > 25%;with the decrease of light intensity,chlorophyll-a,chlorophyll-b,total chlorophyll and the SOD activity all increased gradually,but on the whole,the soluble sugar content decreased;the MDA contents under high light and low light level were higher than others;after treated with 75% of full light,the seedling height,ground diameter growth,biomass of light treatment reached theirs largest values,the root-shoot ratios of the seedlings among under different light intensities had not significant differences,but decreased with light weakened.The suitable light intensity for physiological and growth promoting of O.henryi seedling is about 75% of full sunlight,so the appropriate shading measure in cultivating Ormosia henryi seedlings shoul be adopted.

关 键 词：花榈木 光照条件 生理生化响应 生长效应 

分 类 号：S792.99[农业科学—林木遗传育种]