【作者】 康雯；

【导师】 刘晓东； 何淼；

【作者基本信息】 东北林业大学 ， 园林植物与观赏园艺， 2010， 硕士

【摘要】 本文以地锦(Parthenocissus Tricuspidata)为试验材料,取植株高矮一致,叶量相似,根部形态基本一致的一年生幼苗进行盆栽干旱试验。研究地锦幼苗在土壤自然失水胁迫情况下,各项生理生化指标的变化情况。研究结果表明：1.水分胁迫下,地锦幼苗叶片相对含水量、叶片水势及土壤含水量呈逐渐下降趋势,水分饱和亏缺呈逐渐上升趋势。其中叶片相对含水量与叶片水势在胁迫的前期均保持较高水平,土壤含水量则在胁迫前期下降迅速,而后保持相对平稳。2.水分胁迫下,地锦幼苗的电导率与MDA含量总体呈现上升趋势。且在胁迫前中期,电导率与MDA含量变化并不显著,胁迫21d后,电导率与MDA含量上升迅速。分析表明地锦具有较强的抗旱性,水分胁迫21d为地锦幼苗细胞膜受伤害的临界值。3.水分胁迫下,地锦幼苗叶片的脯氨酸含量、可溶性糖含量、可溶性蛋白含量均呈现逐渐上升的趋势。在胁迫的前21d里,可溶性糖含量的增幅较大,以后变化趋于平缓,差异并不显著。游离脯氨酸含量在胁迫前期变化并不显著,处理21d后,游离脯氨酸含量增加迅速,胁迫越严重增加越迅速。方差分析表明,胁迫21d时差异在0.05水平显著。地锦幼苗叶片中渗透调节物质的增加,说明地锦具有很强的抗旱性。4.水分胁迫下,SOD酶活性先升高后降低；POD活性先降低后升高；CAT活性则逐渐升高并在胁迫最后期出现下降趋势。且SOD与POD活性均在21d时出现峰值,而后保护酶的活性开始降低。说明胁迫21d正是地锦保护酶活性发生变化的阈值,超过这个阈值植物体自身的抗旱性将会降低,从而影响植物的生长发育。因此要保证地锦幼苗能够正常生长,水分胁迫21d为临界值。5.相关性与主成分分析表明,水分胁迫中期,地锦叶片中的可溶性蛋白表现活跃,其与叶片相对含水量、叶片水势、MDA和脯氨酸均表现出显著的相关性。胁迫后期,各项指标间的相关性明显加强。SOD、POD与CAT存在显著的相关性,三种酶相互作用共同增强植物体内保护酶系统的抗旱能力。整个水分胁迫过程各个指标相互补充,协同作用以此来降低干旱对植物的伤害作用。因此,可以说明地锦是具有较强抗旱能力的植物。主成分分析表明,在研究的11项理化指标中,、第一主成分中的叶片水势、相对含水量、相对电导率,第二主成分中POD活性,都是主要与地锦的抗旱能力关系密切的指标。更多还原

【Abstract】 Based on ivy(Parthenocissus Tricuspidata) as test materials, take annual seedlings whose plant height, leaf quantity and root morphology is basically the same for potted drought test. Study on soil natural water stress P. Tricuspidata seedling circumstance, the changes of physiological and biochemical indexes. Research results show:1.Under water stress, the relative water content of leaves, leaf water potential and soil moisture content in P. Tricuspidata is gradually declining trend, water saturation deficit is gradually increasing. Among the relative water content of leaves and potential in the prophase of water stress were higher level, but in the soil moisture content, then fell rapidly stress remained relatively stable.2.Under water stress, P. Tricuspidata seedling conductivity and MDA content overall rising.In the medium-term stress, electric conductivity and MDA in change is not significant, water stress 21 days, electric conductivity and MDA content is rising rapidly.Analysis shows that P. Tricuspidata has strong drought resistance, and the water stress 21 days for P. Tricuspidata seedling damage of membrane.3.under water stress, the content of proline, soluble sugar, soluble protein in P. Tricuspidata seedling all present gradually increasing.In the 21 days prior to the stress, soluble sugar content increases larger, after change tends to gently, difference was not significant.Free proline content is not significant changes in the stress, after 21 days, free proline content increases rapidly, the more serious the more rapidly increasing.Variance analysis showed that when 21 d stress the level is 0.05 significant difference.P. Tricuspidata seedlings leaf osmoregulation substance increased, explain that P. Tricuspidata has a strong drought resistance.4.Under water stress, SOD activity first increased, then decreased;After the first reduce POD activity increased;The CAT activity is gradually increasing and downturn in the late stress.And SOD activity in 21 days with POD by peak, then the protective enzyme activity began to drop.21d stress is that protect enzymes of P. Tricuspidata changing threshold, over the threshold, the drought of plant itself will reduce, thus affect plant growth.Therefore want to normal growth, P. Tricuspidata seedlings under water stress were 21 days for critical value.5.Correlation analysis showed that in the middle of water stress, the leaf of soluble protein in P. Tricuspidata is active, It and the relative water content of leaves, leaf water potential, MDA and proline are showed significant correlation.In the late stress, the indexes in the correlation between obvious strengthening.SOD, POD and CAT significant correlation, three enzymes mutual interaction enhanced plant body first bud enzyme system of drought.The process of water stress each index complement each other, synergy effect so as to reduce the damage to plant drought.The-refore, can explain P. Tricuspidata is strong resistance of plants. Principal component analysis, In this study of 11 physiochemical index, the first principal component of the relative water content, water potential, leaf electrionic conductivity and the second principal components of POD activity, are mainly ability index of close relationship with ivy.更多还原