湿地松优良半同胞家系保护酶活性及脂质过氧化作用对水分胁迫的生理响应

Study on Physiological Response of the Activity of Cell Defense Enzymes and Lipid Peroxidation of Slash Pine’s Half-sib under Water Stress

为研究湿地松优良半同胞家系保护酶及脂质过氧化作用对水分逆境的生理响应,采用盆栽试验和吸光度测定结合的方法,以普通湿地松种子为对照(CK),测定了七个湿地松半同胞家系在正常水分状态(土壤相对含水量为70%)、弱度水分胁迫(土壤相对含水量为55%￣60%)、中度水分胁迫(土壤相对含水量为35%￣40%)和强度水分胁迫(土壤相对含水量为20%￣25%)条件下的SOD、CAT、AsA、MDA的含量和-O2产生速率,研究结果表明:无论是不同水分梯度还是不同家系水平,SOD、CAT、AsA活性和MDA含量的差异均达极显著水平,不同家系水平间-O2产生速率有显著差异,不同水分梯度间-O2产生速率差异达极显著水平。随着水分胁迫程度的加剧,SOD活性和MDA含量增加,二者呈显著线性关系;在水分胁迫初期,CAT活性缓慢增加,至水分胁迫后期,CAT活性增加较快;在水分胁迫初期,AsA活性缓慢增加,至胁迫中期,AsA活性上升较快并达到极大值,至胁迫后期,AsA活性急剧下降;在水分胁迫初期-O2产生速率缓慢下降,至胁迫中期下降幅度较大,至胁迫后期的严重水分胁迫时-O2产生速率略有上升,但此时还未达到胁迫初期的水平。表明在干旱逆境条件下,湿地松各家系体内的SOD、CAT和AsA协调正常运行,清除体内产生的MDA和活性氧等有害物质,避免活性氧和MDA的大量积累,维护其细胞功能性的完整,保护湿地松各家系生理代谢活动不受干扰而能正常生长发育,使其免受伤害。而湿地松半同胞家系与CK的SOD、CAT、AsA、MDA、-O2产生速率在品种之间没有明显的规律性,湿地松半同胞家系在水分胁迫下的保护酶也没有显著的保护优势。

Applied with test of potted plant and measurement absorbency for study physiological response of activity of cell defense enzymes and lipid peroxidafion of slash pine＇s half-sib under water stress. There are 7 families comparison with general slash pine （ab. CK）. The contents of superoxide dismutase（SOD）, catalase （CAT）, antioxidant （AsA）, malondialdehyde （MDA） and the rate of superoxide anion（-O2） generating are mensurated under normal water condition while soil water content is 70% and light water stress while soil water content is 55% to 60% and medium water stress while soil water content is 35% to 40% and heavy water stress while soil water content is 20% to 25%. The test result indicate that either water grads or families of contents of SOD,CAT,AsA,MDA are mighty notable difference. The rate of -O2 generating is notable difference within families. The rate of -O2 generating is mighty notable difference within water grades. The activity of SOD and content of MDA are up with increasing of water stress. The relationship of SOD, MDA and content of soil water is linear. The activity of CAT, AsA increase slowly in primary phase of water stress. Opposite the CAT increase sharply in anaphase of water stress. The activity of AsA up obvious and has maximum in metaphase of water stress. Opposite activity of AsA decline sharply in anaphase of water stress. The rate of -O2 generating decline slowly in primary phase of water stress and continue decline sharply in metaphase of water stress and up slightly in anaphase, but the value of rate of - 02 generating in anaphase is lower than in primary in water stress. They can clean MDA and activity oxygen and other injurant. Escaping MDA and phase. The SOD, CAT, AsA in body of slash pine＇s half-sib have function normal and accordantly activity oxygen accumulate mass and keep full unction of cell and escape disturbing to physiological metabolize of slash pine＇s half-sib and keep them develop normal and escape them injure. The SOD,CAT,AsA,MDA and rate of -O2 generating are not obvious rule within slash pine＇s half-sib and CK on water stress. There are not significant protecting dominance within slash pine＇s half-sib on water stress.