Abstract: Four perennial ryegrass cultivar,‘Neruda’ ‘Accent’ ‘MS’ and ‘AST’,were selected to investigate the effect of ethephon on drought tolerance of turfgrasses. Plants of each cultivar were divided into two groups:ethephon treated (ETH) and non-ethephon treated control group (CK). Plants were subjected to four treatment conditions:well-watered,5-day-drought,10-day-drought and 2 day of re-watering treatment. The effects of ethephon on the drought tolerance of perennial ryegrass were investigated through measuring grass physiological parameters,including leaf relative water content,electrolyte leakage,proline content,antioxidant enzyme activities (POD,CAT,APX). Main results were as following:Leaf relative water content,EL,and proline content drought conditions were improved by spraying ethephon on leaves. Ethephone treatment promoted POD activity in ‘MS’ and ‘AST’. The effects of ethephon treatment on CAT and APX enzyme activities were not significant under drought conditions. Ethephon alleviated the increase of proline due to drought treament. After 2 days of re-watering,leaf relative water content did not return to the pre-stressed level,electrolyte leakage returned to pre-stressed level,and proline content did not decrease to the pre-stressed level. To sum up,leaf application of ethephon can relieve drought damages for cultivars of perennial ryegrass to different extent,and also promote the recovery rate in RWC and proline upon re-watering treatment.

Key words: Perennial Ryegrass, Ethephon, Drought Resistance

摘要： 本研究以‘Neruda’，‘Accent’，‘MS’，‘AST’4个品种多年生黑麦草（Lolium perenne L.）为试验材料，研究叶片喷施乙烯利对多年生黑麦草耐旱性的影响。结果表明，喷施乙烯利后干旱处理10 d时，‘Neruda’、‘MS’和‘AST’叶片相对含水量显著提高，所有品种电解质渗透率均下降，‘Neruda’、‘Accent’和‘MS’脯氨酸含量的上升减缓，同时喷施乙烯利提高了‘MS’、‘AST’的过氧化物酶（Peroxidase，POD）活性，但对过氧化氢酶（Catalase，CAT）和抗坏血酸过氧化氢酶（Ascorbate peroxidase，APX）活性影响不显著。复水2 d后，乙烯利促进了‘MS’品种相对含水量和‘Neruda’品种脯氨酸含量的恢复。因此，叶片喷施乙烯利可以不同程度缓解多年生黑麦草干旱条件下的胁迫损伤，一定程度上提高干旱复水后的恢复能力。

关键词: 多年生黑麦草, 乙烯利, 耐旱性