CAJ | 학술논문

以2种不同耐旱性的鸭茅基因型（敏感型“01998”和耐旱型“宝兴”）为研究对象，研究干旱胁迫下鸭茅根、叶膜质过氧化作用，渗透调节和保护酶活性的生理变化，探讨鸭茅耐旱机制。结果表明，随着干旱胁迫时间的延长，2种基因型鸭茅根系及叶片电导率，丙二醛含量逐渐增加，渗透调节物质可溶性糖和游离脯氨酸不断积累，而可溶性蛋白含量、超氧化物歧化酶、过氧化氢酶、过氧化物酶和抗坏血酸过氧化物酶活性呈先上升后下降趋势。其中，叶片脂膜过氧化产物 MDA累积和膜透性增幅较大，说明在持续的干旱胁迫下叶片所受伤害重于根系。而渗透物质积累方面，叶片中可溶性糖和可溶性蛋白的含量高于根系，而根系中的游离氨基酸的相对增加量则大于叶片，这可能与叶片是糖的主要产生部位，而根系则可以合成氨基酸有关。研究还表明，干旱胁迫第24天，耐旱型品种“宝兴”根系及叶片 APX、POD活性显著高于“01998”表明重度干旱胁迫并没有降低 APX和 POD酶清除 H2 O2和单态氧的能力，说明“宝兴”鸭茅在干旱条件下抗氧化清除系统响应更积极、更持久。
이2충불동내한성적압모기인형（민감형“01998”화내한형“보흥”）위연구대상，연구간한협박하압모근、협막질과양화작용，삼투조절화보호매활성적생리변화，탐토압모내한궤제。결과표명，수착간한협박시간적연장，2충기인형압모근계급협편전도솔，병이철함량축점증가，삼투조절물질가용성당화유리포안산불단적루，이가용성단백함량、초양화물기화매、과양화경매、과양화물매화항배혈산과양화물매활성정선상승후하강추세。기중，협편지막과양화산물 MDA루적화막투성증폭교대，설명재지속적간한협박하협편소수상해중우근계。이삼투물질적루방면，협편중가용성당화가용성단백적함량고우근계，이근계중적유리안기산적상대증가량칙대우협편，저가능여협편시당적주요산생부위，이근계칙가이합성안기산유관。연구환표명，간한협박제24천，내한형품충“보흥”근계급협편 APX、POD활성현저고우“01998”표명중도간한협박병몰유강저 APX화 POD매청제 H2 O2화단태양적능력，설명“보흥”압모재간한조건하항양화청제계통향응경적겁、경지구。
To elucidate the mechanism of drought tolerance in orchardgrass,the different responses associated with lipid peroxidation,osmotic adj ustment and activity of protective enzymes in the root and leaf to drought stress of two different genotypes of orchardgrass (drought-sensitive “01998”and drought-tolerant “Baoxing”) were investigated.With an extension of drought stress,MDA content and electrolyte leakage in the root and leaf of the two orchardgrasses increased,and total soluble sugar content and free proline content also accumula-ted.At the same time,soluble protein content,SOD,CAT,POD,APX activities increased initially and then decreased.The accumulation of leaf MDA content and membrane permeability grew fast,indicating that dam-age on the blades was far more serious than on roots under constant drought stress.Accumulation of osmotic substances,leaf soluble sugar and soluble protein content were higher in shoots than in the roots,while the rel-ative increase of free amino acid was greater in the roots.This might be because the blade is the main area for sugar production,whereas the root system is closely related to the synthesis of amino acids.In addition,APX and POD activities in the roots and leaves of“Baoxing”were higher than those in“01998”under 24 d drought stress,indicating that its ability to scavenge singlet oxygen and H2 O2 was not weakened by drought stress. Drought tolerant “Baoxing”showed more active and stable peroxidation ability under drought stress.