【作者】 许丽颖；

【导师】 郭太君；

【作者基本信息】 吉林农业大学 ， 果树学， 2007， 硕士

【摘要】 本文以绿叶树种长李15号和彩叶树种紫叶李为试材，首次探讨了干旱和遮荫环境胁迫对两种叶片颜色不同的李树品种的光合色素、花色素含量、PAL酶活性、可溶性糖含量、叶片pH值的变化规律。对李树特别是紫叶李的园林应用具有重要意义，也为今后的李树生产应用提供了理论依据。研究结果表明：1．干旱胁迫使长李15号和紫叶李的光合色素含量下降。但不同的光合色素种类、不同品种对干旱胁迫敏感程度有差异。叶绿素对干旱胁迫的敏感性大于类胡萝卜素，干早胁迫对叶绿素b的伤害大于叶绿素a，到重度胁迫时，两个品种叶绿素b含量分别比对照降低了32.9％和37.7％。在品种方面，紫叶李较长李15号对干旱胁迫敏感。而遮荫与干旱胁迫相反，遮荫使长李15号和紫叶李叶绿素a、叶绿素b、类胡萝卜素和总叶绿素含量增加，这是使植株更好的适应弱光的一种反应。2．干旱胁迫使长李15号和紫叶李的叶绿素a／b值逐渐增加，进一步说明干旱胁迫使叶绿素b受到的伤害大于叶绿素a，叶绿素／类胡萝卜素、叶绿素／花色素逐渐减少，叶片颜色鲜艳；遮荫使李树的叶绿素a与叶绿素b比值逐渐降低，表明遮荫对叶绿素b的增幅较大，叶绿素／类胡萝卜素、叶绿素／花色素的比值均逐渐增加，叶片呈现返青现象。因此，干旱胁迫与遮荫环境下，引起叶片颜色变化的主要原因是叶绿素与花色素的比例发生了变化。3．干旱胁迫使长李15号和紫叶李的花色素含量，PAL酶活性和可溶性糖含量明显升高，pH值逐渐减少。PAL活性和花色素含量的变化不同步，说明干旱胁迫使紫叶李叶片花色素含量上升，与PAL活性有一定关系，但PAL不是紫叶李叶片花色素合成的唯一调节酶。而遮荫使两个品种的花色素含量，PAL酶活性，可溶性糖含量逐渐降低，三者间呈正相关，说明紫叶李叶片花色素含量形成，与PAL活性关系密切。表明了不同的环境条件下，紫叶李叶片花色素合成调节机制不同。4．干旱胁迫下，紫叶李叶片总叶绿素、叶绿素a、叶绿素b含量下降，花色素含量上升，花色素与叶绿素含量的比值增加，使叶片显色更加明显。因此，在园林绿地栽培养护管理时，应创造土壤含水量50％～60％的环境，可提高紫叶李的观赏效果。6．遮荫环境下，紫叶李叶片总叶绿素、叶绿素a、叶绿素b含量上升，花色素含量和花色素与叶绿素含量的比值下降，叶片出现复绿现象，不利于叶片显色。在园林配植时应尽可能地提高透光率，才可能使紫叶李叶片有较高的观赏性。更多还原

【Abstract】 The paper takes ChangLi 15 in green leaf and Purple leaf plum in colorful leaf as materials, analyzes the change rule of photosynthetic pigment content, flower pigment content, PAL activity, soluble sugar content, leaf pH value with two species of different colorful leaf under water stressand shading condition, The results can be summarized as follows:1. The Photosynthetic pigment content is decreased under water stress condition. But thesensitive extent under water stress are differences in different photosynthetic pigment species andbreed, cha+b is larger than carotinoid, damage of ch b caused by water stress is more than that ofch a in the species, compare with the ck, ch b is decreased 32.9% and 37.7% of two species whenHeavy degrees of forces, Purple leaf plum’ s sensitivity caused by water stress are more thanChangLi 15. But the results of shading condition are contrary to that under water stress, that is, cha and ch b, carotinoid and cha+b content are all increased, this is the reaction for trunk of tree tosuit the week light.2. Under water stress condition, ch a/b of plums are increased, so say that the damage of ch bcaused by water stress is more than that. of ch a, and value of cha+b/ carotinoid and cha+b/flower pigment are both reduced in ChangLi 15 and Purple leaf plum, the color of the leaf is moreobvious; Under shade environment, ch a/b is reduced. It shows that increased range of ch bcontents is bigger. And value of cha+b/ carotinoid and cha+b/ flower pigment is increased, thecolor of the leaf is went to green. So the effect on color of the leaf is the ratio variety of cha+b andflower pigment under water stress and shading.3. Under water stress condition, flower pigment content and soluble sugar content and PALactivity of two species are obviously increased, and pH value is gradually reduced. The rule ofPAL activity and flower pigment contents is not at the same time. This shows that the increasedflower pigment contents of Purple leaf plum are related to PAL activity, but the PAL not the onlyregulatory enzyme of flower pigment composite. While under shade environment, contents offlower pigment content and soluble sugar content and PAL activity of two species are all graduallyreduced, and the three is positive correlation. Say that the formation of the flower pigment iscorrelation to PAL. So under different condition, the formation of the flower pigment is different.4. With the study of Photosynthetic pigment under water stress and shading, that shows theendurance of drought ability, ChangLi 15 is higher than Purple leaf plum, the endurance ofshading, Purple leaf plum is higher than Changli 15.5. The chlorophyll, ch a and ch b content of Purple leaf plum is reduced, flower pigmentcontent is increased, flower pigment and chlorophyll value is increased under water stress, madethe color of the leaf is more obviously. So make the soil water content of 50%～60% can enhancethe view and admire impact, while conserve and manage with gardens greenbelt growth.6. The chlorophyll, ch a and ch b content of Purple leaf plum is increased, flower pigmentcontent is reduced, flower pigment and chlorophyll value are reduced under shading, the leaf isgreen, make against the color of leaf. Try to improve transmittance is ensure when gardens match, then the view and admire of Purple leaf plum will big.更多还原