单 位：
福建农林大学林学院;福建省林业科学研究院
摘 要：
以一年龄台湾海桐(Pittosporum pentandrum)盆栽苗为试材,采用人为称重控水方法,研究了正常供水(CK)、轻度干旱胁迫(LD)、中度干旱胁迫(MD)和重度干旱胁迫(HD)4种水分处理对台湾海桐生长和生理生化特性的影响,以探讨台湾海桐耐旱机制。结果显示,随干旱胁迫程度的加剧,台湾海桐幼苗高度和生物量下降,根冠比增加;净光合速率(Pn)、蒸腾速率(Tr)、气孔导度(Gs)、气孔限制值(Ls)和水分利用效率(WUE)降低,胞间CO2浓度(Ci)增加;叶中K+和Mg2+含量降低,Ca2+含量先增加后降低;叶中可溶性糖和可溶性蛋白质含量增加,叶中脯氨酸含量先增加后降低;叶中丙二醛(MDA)含量和质膜透性增加,过氧化氢酶(CAT)、过氧化物酶(POD)、超氧化物歧化酶(SOD)和抗坏血酸过氧化物酶(APX)活性先增加后降低。干旱胁迫下台湾海桐幼苗生长受到抑制和膜脂过氧化加剧,但其能通过对渗透调节物质的含量和抗氧化酶系统的活性调节来保护膜结构,保持正常的生理活动,表现出一定的抗旱能力。
译 名：
Effects of drought stress on growth and physiological and biochemical characteristics of Pittosporum pentandrum
作 者：
LIN Wu-xing;GU Ling;ZHU Wei;NIE Sen;Fujian Academy of Forestry;College of Forestry,Fujian Agriculture and Forestry University;
关键词：
Pittosporum pentandrum;;drought stress;;growth;;physiological and biochemical characteristics
摘 要：
In order to explore the mechanism of drought-tolerance of Pittosporum pentandrum,the growth and physiological and biochemical characteristics of 1-year-old P. pentandrum seedlings were analysis under four levels of drought stress including optimal water content( CK),mild drought stress( LD),moderate drought stress( MD) and heavy drought stress( HD) which were controlled by weighing the soil and pots. With the increase of drought stress,the heights and biomass of the seedlings decreased but the root /shoot ratio increased; net photosynthesis rate( Pn),transpiration rate( Tr),stomatal conductance( Gs),stomatal limitation( Ls) and water use efficiency( WUE) decreased while intercellular CO2concentration( Ci) increased; the contents of K+and Mg2 +decreased while the content of Ca2 +firstly increased and then decreased; the contents of soluble sugar and soluble protein increased while the content of proline firstly increased and then decreased; the contents of malondialdehyde and membrane permeability increased but the activity of catalase( CAT),peroxidase( POD),superoxide dismutase( SOD) and ascorbate peroxidase enzyme( APX) firstly increased and then decreased. These results indicated that the membrane lipid peroxidation increased and the growth was inhibited under drought stress. However,P. pentandrum protected the membrane structure and maintained normally physiological activity through improving the activities of the antioxidant enzymes system and accumulating osmotic regulation such as soluble sugar,proline,soluble protein and Ca2 +which improve its tolerance to the drought stress.
