采用盆栽实验方法,研究了不同透光率(100% 、50% 、25% 和 15% )和土壤含水量(10% 、25% 、45% 和 65% )对夏蜡梅(Sinocalycanthus chinensis Cheng et S. Y. Chang)枝条生长量和叶片部分生理指标的影响,并对枝条生长量和叶片各生理指标间的相关性进行了分析。 结果表明:在土壤含水量 10% 或全光照(透光率 100% )条件下,夏蜡梅枝条生长量和叶片的叶绿素含量最低,MDA 和可溶性糖含量以及 SOD 和 POD 活性均较高,脯氨酸和可溶性蛋白质含量最高;在透光率 50% 和 25% 或土壤含水量 25% 和 45% 的条件下,枝条生长量和叶片的叶绿素含量提高,其他各项生理指标则有所降低;在透光率 15% 或土壤含水量 65% 的条件下,枝条的生长量和叶片叶绿素含量略有减小,其他各项生理指标则有所提高。 总体上,随透光率的提高和土壤含水量的减小,夏蜡梅枝条生长量和叶片叶绿素含量呈逐渐减小的趋势,其他各项生理指标呈逐渐提高的趋势。 透光率和土壤含水量对夏蜡梅枝条生长量及叶片的生理指标有交互作用,遮阳可在一定程度上缓解土壤干旱胁迫对夏蜡梅的伤害,增加土壤含水量也可在一定程度上缓解强光照对夏蜡梅的伤害;但透光率过低(15% )或土壤含水量过高(65% )则不利于夏蜡梅的生长。 相关性分析结果表明,枝条生长量与叶片 POD 活性、脯氨酸和 MDA 含量呈极显著的负相关(P<0. 01),说明在胁迫条件下叶片这 3 项指标的变化与夏蜡梅枝条生长紧密相关,可通过这些指标判定夏蜡梅对其生境的适应程度。 根据实验结果推测,在夏季高温阶段,夏蜡梅适宜在透光率 50% 、土壤含水量 45% 的生境中生长,在上海地区种植夏蜡梅应适当配植乔木和地被植物。

The influences of different transmittance (100% , 50% , 25% and 15% ) and different water contents in soil (10% , 25% , 45% and 65% ) on branch increment and some physiological indexes in leaf of Sinocalycanthus chinensis Cheng et S. Y. Chang were researched by pot experiment method, and the correlation among branch increment and physiological indexes in leaf was also analyzed. The results show that under 10% water content in soil or full illumination (100% transmittance) conditions, the branch increment and chlorophyll content in leaf of S. chinensis is the lowest, contents of MDA and soluble sugar, activities of SOD and POD all are higher, and contents of proline and soluble protein are the highest. Under the conditions with 50% and 25% transmittance or 25% and 45% water contents in soil, the ranch increment and chlorophyll content in leaf increase, while other indexes all decrease to some extent. Under the conditions with 15% transmittance or 65% water content in soil, the branch increment and chlorophyll content in leaf decrease slightly, while other indexes all increase to some extent. In general, with enhancing of transmittance or reducing of water content in soil, the branch increment and chlorophyll content in leaf appear the trend of decreasing gradually, while other indexes all appear the trend of increasing gradually. The transmittance and water content in soil have the alternate effects on the branch increment and physiological indexes in leaf of S. chinensis, and the shading can reduce the injury of soil drought stress on S. chinensis to a certain extent while increasing of water content in soil can also reduce the injury of strong light on S. chinensis to a certain extent. But too low transmittance (15% ) or too high water content in soil (65% ) are unfavorable to growth of S. chinensis. The correlation analysis result shows that there are extremely significant negative correlation of the branch increment with POD activity, proline content and MDA content ( P<0. 01), indicating that the branch increment of S. chinensis is closely related to the change of these three indexes in stress environment, therefore, the adapt degree of S. chinensis to habitat can be judged by means of above three indexes. According to these experiment results, it is conjectured that S. chinensis is suitable for growing in the habitat with 50% transmittance and 45% water content in soil under high tempreture in summer and should be planted together with arbors and ground cover plants in Shanghai area.