关键词：
台湾海桐;台湾栾树;抗氧化酶;有机溶质;耐盐性
摘 要：
为了比较引进福建的台湾海桐和台湾栾树的耐盐性,以盆栽台湾海桐和台湾栾树1年生实生苗为对象,研究了6、9、12和15 g·kg-1的盐浓度胁迫下其苗高生长量、生物量、叶片丙二醛(MDA)含量、抗氧化酶活性[超氧化物歧化酶(SOD)、抗坏血酸过氧化物酶(APX)和谷胱甘肽还原酶(GR)]的影响,以及植株脯氨酸和可溶性蛋白质水平在盐胁迫下的变化,探讨2树种的盐适应措施。结果表明:(1)盐胁迫抑制了2树种的苗高生长和生物量积累,台湾海桐根冠比增加,台湾栾树根冠比先减少后增加。(2)台湾海桐和台湾栾树的生长临界盐浓度分别为8.8和6.6 g·kg-1。(3)高盐下,台湾海桐和台湾栾树叶MDA含量均显著升高,且台湾栾树的MDA含量始终高于台湾海桐。(4)盐胁迫下,与台湾栾树相比,台湾海桐叶能维持较高的SOD、APX和GR活性。(5)盐胁迫下台湾海桐和台湾栾树叶脯氨酸及可溶性蛋白质含量均显著上升,但前者叶的脯氨酸和可溶性蛋白质含量始终高于后者。上述表明,2树种盐适应机制不同,台湾海桐具有一定的耐盐性,而台湾栾树采取避盐策略求得生存,且前者盐适应能力高于后者;台湾海桐耐盐性较高的原因可能主要在于,盐胁迫下,其能启动抗氧化酶系统、积累脯氨酸和可溶性蛋白质等物质的能力要优于台湾栾树。
译 名：
Changes of antioxidant metabolism and organic solute accumulation of Pittosporum pentandrum and Koelreuteria elegans seedlings under salt stress
作 者：
HUANG Yong-rong;LIN Wu-xing;NIE Sen;ZHU Wei;Fujian Academy of Forestry;
关键词：
Pittosporum pentandrum;;Koelreuteria elegans;;antioxidant enzymes;;organic solutes;;salt tolerance.
摘 要：
Pittosporum pentandrum and Koelreuteria elegans,native to Taiwan Island,exhibit strong abilities of wind and salt tolerance. Although the field trials have proved their adaptation to the stressful environments of coastal zone,little information is available to understand their measures of salt tolerance. In the current study,the effects of salt stress on the growth and antioxidant metabolism of one-year old seedlings of P. pentandrum and K. elegans were studied under Na Cl concentrations of 6,9,12 and 15 g·kg-1. The results showed that,( 1) The height and biomass of P. pentandrum and K. elegans seedlings decreased with the increase of Na Cl concentration. Meanwhile,the root / shoot ratio increased for P. pentandrum,while decreased firstly and then increased for K. elegans.( 2) The tolerance threshold values of P. pentandrum and K. elegans to Na Cl concentration were 8. 8 and 6. 6 g·kg-1,respectively.( 3) The MDA content in each of the two species increased under high salt stress,but was higher in K. elegans than in P.pentandrum.( 4) SOD,APX and GR activities of P. pentandrum leaves under Na Cl stress were higher than those of K. elegans leaves.( 5) Proline and soluble protein contents of P. pentandrum leaves were higher than those of K. elegans leaves and they both increased significantly under Na Cl stress. The above results indicated that the salt-adaptation mechanisms of P. pentandrum and K. elegans were different,and P. pentandrum and K. elegans were salt-resistance and salt-avoidance species,respectively. The salt-tolerance ability of former was stronger than that of latter. The stronger salt-tolerance ability of P. pentandrum may be related to its stronger antioxidant enzyme system and higher capability to accumulate proline and soluble protein under salt stress.
