CAJ | 학술논문

研究羊草对盐碱胁迫生理响应特征，旨在找出羊草耐盐碱范围及其对盐碱地改良的应用潜力。通过模拟5组不同盐碱梯度土壤胁迫试验（pH值为7.61、8.05、8.33、8.73、9.37，电导率为0.109、0.301、0.437、0.486、0.591 mS/cm），研究了羊草体内离子含量和运输能力、有机小分子渗透调节和保护酶活性变化。结果表明，盐碱胁迫由低到高，超氧化物歧化酶和甜菜碱在中度盐碱胁迫（pH值8.33，电导率0.437 mS/cm）积累最多，其他测定的耐盐碱物质，钠离子、脯氨酸、丙二醛、有机酸（草酸、柠檬酸、酒石酸）、过氧化物酶、过氧化氢酶、可溶性总糖、可溶性蛋白均呈直线增加。在盐碱胁迫条件下，羊草叶片中积累的钾离子、甜菜碱、有机酸、可溶性蛋白高于根茎，而脯氨酸、丙二醛、保护酶（超氧化物歧化酶、过氧化物酶、过氧化氢酶）、可溶性总糖叶片中含量低于根茎。根茎大量积累保护酶、脯氨酸及丙二醛有助于防止盐碱环境下根茎中膜过氧化，并保持根茎正常的渗透调节能力，从而有利于将K+等养分运送到叶片。在盐碱胁迫下，羊草叶片主要积累甜菜碱和有机酸进行渗透调节。该试验结果表明，羊草根茎和叶片在不同盐碱胁迫条件下各耐盐碱生理指标均产生一系列适应性反应，使其在盐碱环境正常生长，进而降低土壤盐碱性。该研究可为耐盐碱饲草选育及根茎型禾草改良盐碱化草地提供理论和实践依据。
연구양초대염감협박생리향응특정，지재조출양초내염감범위급기대염감지개량적응용잠력。통과모의5조불동염감제도토양협박시험（pH치위7.61、8.05、8.33、8.73、9.37，전도솔위0.109、0.301、0.437、0.486、0.591 mS/cm），연구료양초체내리자함량화운수능력、유궤소분자삼투조절화보호매활성변화。결과표명，염감협박유저도고，초양화물기화매화첨채감재중도염감협박（pH치8.33，전도솔0.437 mS/cm）적루최다，기타측정적내염감물질，납리자、포안산、병이철、유궤산（초산、저몽산、주석산）、과양화물매、과양화경매、가용성총당、가용성단백균정직선증가。재염감협박조건하，양초협편중적루적갑리자、첨채감、유궤산、가용성단백고우근경，이포안산、병이철、보호매（초양화물기화매、과양화물매、과양화경매）、가용성총당협편중함량저우근경。근경대량적루보호매、포안산급병이철유조우방지염감배경하근경중막과양화，병보지근경정상적삼투조절능력，종이유리우장K+등양분운송도협편。재염감협박하，양초협편주요적루첨채감화유궤산진행삼투조절。해시험결과표명，양초근경화협편재불동염감협박조건하각내염감생리지표균산생일계렬괄응성반응，사기재염감배경정상생장，진이강저토양염감성。해연구가위내염감사초선육급근경형화초개량염감화초지제공이론화실천의거。
Salinization of grassland is one of the main causes of the degeneration of Leymus chinensis grassland in north-eastern part of China. In this study, we sampled L. chinensis as experimental materials, simulated in five soil stresses under different salinization gradient intensity (pH values were 7.61, 8.05, 8.33, 8.72, 9.37, the corresponding electrical conductivity were 0.109, 0.301, 0.438, 0.486, 0.591 dS/m ) during a 120-day period from the beginning of spring to the end of fall. Then we measured ion content and transport capacity, osmotic adjustment of small organic molecules and the change of protective enzymatic activities to understand the range and the mechanism of L. chinensis adapting to saline-alkali stress. The results illustrated that with the increase of saline-alkali stress, superoxide dismutase (SOD) and betaine were accumulated to the maximum under moderate saline-alkaline stress A3. The content of Na+, proline, malonaldehyde (MDA), organic acids (oxalic acid, citric acid, tartaric acid), catalase (CAT), peroxidase (POD), soluble protein and total soluble sugar showed a linear increase with the increase of saline-alkaline stress. However, the content of K+and K+/Na+indicated a contrary tendency and the differences were also significant (P<0.05). Under the different levels of saline-alkali stress, the selective transportation index of K+ (STK-Na) which was from rhizome to tiller had no significant difference between five groups (P>0.05). It showed that L. chinensis was able to still regulate K+, and transport them from rhizome to leaf. Under the saline-alkali stress, a higher accumulation of K+, betaine, organic acids and soluble protein in leaf was observed than did in rhizome. However, proline, MDA, protective enzyme (CAT, POD, SOD) and total soluble sugar in leaf were lower than the ones observed in rhizome. Under the saline-alkali stress, CAT activity was on the top among the protective enzymes ranging from 11121.74 to 213345.2 U/g, followed by POD from 538.94 to 1570.337 U/g, and SOD from 60.17 to 106.86 U/g. Under the saline-alkali stress, CAT had the strongest effect to the antioxidation of L. chinenesis, which was the most important to maintain the completion of cytoplasmic membrane. MDA increased largely along with the increase of saline-alkali stress, which indicated that the L. chinensis membrane had been damaged. The damage intensity of rhizome was more serious than the injuries of leaves. The accumulation of protective enzymes, proline and MDA helped rhizome to prevent membrane from peroxidation under saline-alkaline stress, and kept normal osmotic adjustment ability, through which, contributing to transporting K+and other nutrients to the leaves. Under saline-alkali stress, the leaves of L. chinensis carried out osmotic adjustment mainly through accumulation of betaine and organic acids. Our results indicated that L. chinensis was likely to exert a series of adaptable response on its physiology by the different soil conditions varied in salinization gradients.