干旱胁迫对文冠果幼苗的生理反应及生长的影响

摘要

In pot experiment,we selected sorbifolia seedlings as tested materials and set different moisture gradients to study sorbifolia seedlings for drought stress tolerance characteristics.The physiological and growth properties of sorbifolia seedlings under different soil moisture gradients and different times were analyzed.The result showed that (i) The malondialdehyde (MDA) content of sorbifolia leaf and cell membrane permeability (RCM) remained relatively stable in the control and T2 treatments over time,the T1,T3 and T4 treatments showed increasing trend.(ii) The osmotic adjustment substances,eg.soluble sugar (SS) and proline (Pro) content of leaves increased gradually in T3 and T4 treatments,increased firstly and then decreased in T1 treatment,soluble protein (SP) content in the T1 and T4 treatments exhibited increased after decreased,and compared to control treatment,different osmolytes content was closer in T2 treatment.(iii) Superoxide dismutase (SOD),peroxidase (POD),catalase (CAT) activities in T1,T3 and T4 treatments were higher than that of the control treatment,but the changes of time and amplitude were different.(iv) In sorbifolia height,diameter,number of leaves and organ biomass accumulation,T1 and T4 treatment decreased significantly (P ＜ 0.05) compared with the control treatment,but the long taproots were generally exhibited T4 ＞ T3 ＞ T1 ＞ T2 ＞ CK,the difference was significant (P ＜ 0.05),the main root length in T4,T3 and T1 treatments improved 68.4 ％,54.5 ％ and 41.5 ％,respectively,compared with the control treatment.Seedlings of Xanthoceras sorbifolia could improve their drought resistance by regulating their growth,protecting enzyme activity and soluble matter content.%为了研究文冠果幼苗对干旱胁迫的耐受特性,选择2年生文冠果幼苗为供试材料.在盆栽条件下,设置水分梯度,测定分析文冠果幼苗在不同水分梯度及不同时间下的生理指标及生长指标.结果表明,①随着时间的延长,文冠果叶片丙二醛(MDA)含量及细胞膜相对透性(RCM)在对照和T2处理下保持相对稳定,而在T1、T3及T4处理下有升高的趋势.②文冠果叶片内渗透调节物质可溶性糖(SS)和脯氨酸(Pro)含量在T3和T4处理下逐渐升高,T1处理下先升高后降低,而可溶性蛋白(SP)的含量则在T1和T4处理下呈先升高后降低的趋势,T2与对照处理各渗透调节物质含量较为接近.③文冠果叶片的超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)活性在T1、T3及T4处理下均高于对照,但变化的时间和幅度有所不同.④在文冠果株高、地径、叶数及各器官生物量积累方面,T1和T4处理显著低于对照(P＜0.05),但主根长则大体表现出T4 ＞T3 ＞T1＞T2＞CK,差异显著(P＜0.05),T4、T3及T1处理的主根长分别较对照提高了68.4％、54.5％及41.5％.文冠果幼苗能通过调整自身生长、保护酶活性和可溶性物质含量等提高其抗旱性.