干旱胁迫对4种观赏草枯叶率及生理指标的影响

为了解观赏草的抗旱机制,在盆栽控水条件下,对红叶白茅(Imperata cylindrical‘Red Baron’)、花叶芒(Miscanthus sinensis‘Variegatus’)、斑叶芒(Miscanthus sinensis‘Zebrinus’)和花叶虉草(Phalaris arundinaceavar.picta)4种观赏草进行了外观形态及生理生化响应研究。结果表明:随着干旱胁迫的加剧,4个草种的土壤含水量、叶片相对含水量(RWC)均呈下降趋势,枯叶率、叶片细胞质膜透性(REC)、丙二醛(MDA)含量、脯氨酸(Pro)含量均呈上升趋势;超氧化物歧化酶(SOD)活性和可溶性蛋白含量均呈先上升后下降的变化趋势。抗旱性强的草种RWC下降最慢,枯叶率、REC,以及MDA和Pro含量上升幅度低于抗旱性弱的草种。综合评价4种观赏草的抗旱性顺序为斑叶芒>花叶芒>红叶白茅>花叶虉草。

Effect of Drought Stress on Withered Leaf Rate and Physiological Indices of Four Ornamental Grasses

Drought and water shortage have become significant factors restricting quick development of garden landscape in China.The response of the morphological and physiological parameters of four ornamental grass speciesJapanese blood grass(Imperata cylindrical ’Red Baron’),Variegated miscanthus(Miscanthus sinensis ’Variegatus’),Zebra grass(Miscanthus sinensis ’Zebrinus’)and Gardener’s garters(Phalaris arundinacea var.picta)] to drought stress was investigated by measuring soil water content,withered leaf rate,leaf relative water content(RWC),leaf relative electrolytic leakage(REC),malondialdehyde(MDA) content,superoxide dismutase(SOD) activity,proline(Pro) and soluble protein content for 21 days.Results showed that soil water content and leaf relative water content of four grass species decreased continuously;withered leaf rate,leaf relative electrolytic leakage,MDA and Pro content of four species increased continuously with prolonged drought stress;SOD activity and soluble protein content increased at initial drought stress then decreased.According to all morphological and physiological parameters evaluation,the drought tolerance of four species was ranked in order: Zebra grass>Variegated miscanthus>Japanese blood grass>Gardener’s garters.