盐胁迫下3种外源物对高羊茅生理指标的影响

Effects of three exogenous substances on the physiological indexes of tall fescue under salt stress

为探讨如何提高高羊茅(Festuca arundinace)对盐胁迫的适应能力,本研究以高羊茅为研究对象,通过盆栽试验探究盐胁迫(NaCl)下叶面喷施硫酸钾(K_(2)SO_(4))、甜菜碱(glycine betaine,GB)和抗坏血酸(ascorbic acid,AsA)对草坪质量(turf quality,TQ)、叶片相对含水量(relative water content,RWC)、渗透调节能力(osmotic adjustment)、电解质渗漏率(electrolyte leakage,EL)、丙二醛含量(malonaldehyde content,MDA)、离子含量和抗氧化物酶的影响。结果表明,叶面喷施K2SO4、GB、AsA均能在一定程度上提高高羊茅的耐盐能力,其中以喷施GB效果最佳,AsA次之。与其他处理相比,喷施GB可以更有效地改善盐胁迫下高羊茅草坪质量,并抑制叶片相对含水量的下降,同时叶片具有较高的渗透势和较低的电解质渗漏率。此外,GB处理可以明显抑制叶片中丙二醛和H_(2)O_(2)的积累,同时在延缓过氧化氢酶(catalase,CAT)和抗坏血酸过氧化物酶(ascorbate peroxidase,APX)活力下降方面效果显著。以上结果表明,外源GB处理可以提高高羊茅的渗透调节能力和抗氧化酶活性,进而提升其耐盐能力。

To determine the adaptability to salt stress,tall fescue(Festuca arundinace) was taking as the material to examine the effects of three exogenous compounds such as potassium sulfate(K_(2)SO_(4)),glycine betaine(GB),and ascorbic acid(As A)on salinity resistance.Turf quality(TQ),relative water content(RWC),osmotic adjustment,electrolyte leakage(EL),malonaldehyde content(MDA),ion content,and antioxidant enzymes were measured in tall fescue under non-stresssed and salt stressed conditions.The results showed that spraying K_(2)SO_(4),GB,and As A could improve salt resistance of tall fescue to some extent.Overall,spraying GB had the best performance,followed by As A.Compared with other treatments,spraying GB improved the quality of tall fescue under salt stress more effectively and inhibited the decrease of relative water content of leaves;however,leaves had higher osmotic potential and lower electrolyte leakage rate.In addition,GB treatment had a significant effect in inhibiting the accumulation of malondialdehyde and H_(2)O_(2),and delaying the decrease of catalase and ascorbate peroxidase enzyme activities.Overall,this study confirms that exogenous GB treatment can improve the osmotic regulation ability and activity of antioxidant enzyme on tall fescue,consequently improving the resistance of salt tolerance.