草业学报2016，Vol.25Issue(6)：51-61,11.DOI:10.11686/cyxb2015409
赤霉素对干旱胁迫下高羊茅萌发及幼苗生长的缓解效应
Effects of gibberellin on seed germination and seedling growth of tall fescue under drought stress
摘要
Abstract
This study investigated the effects of gibberellin concentrations on seed germination and seedling growth of tall fescue (Festuca arundinacea )under drought stress.The seed germination experiment was con-ducted at 5 polyethylene glycol (PEG)levels (0%,5%,10%,15% and 20%)after soaking seeds in 5 gibber-ellin concentrations (0,100,200,300 and 400 mg/L).The malondialdehyde concentration (MDA)and electri-cal conductivity of seeds were determined before germination,then the seedling growth,seed germination rate and potential were measured during germination.The electrical conductivities of seeds soaked in 0 and 100 mg/L gibberellin were significantly (P ≤0.05)higher than those of seeds soaked at the other three gibberellin concentrations,and MDA concentrations of seeds soaked with 0 and 100 mg/L gibberellin solution were signifi-cantly lower (P ≤0.05)than those of seeds soaked at the three higher gibberellin concentrations.Compared to seeds soaked in pure water,the 5% and 10% PEG treatments had,respectively,47.06% and 37.33% greater germination potential,and 19.46% and 16.95% higher germination rate.However,the germination rate,and root and bud length were obviously decreased when the PEG concentration was 15% or higher.After soaking in 200 mg/L gibberellin solution,root length was increased 53.26%,30.12% (compared with soaking in pure water)and the corresponding increases in bud length were 79.87% and 50.75% at 5% and 10% PEG solu-tions.The effect of gibberellin decreased with increase in PEG level.The inhibition of PEG stress on bud length was stronger than on root length,but the root length:bud length ratio was obviously decreased water after gibberellin treatment,compared to that of seeds soaked in pure.In summary,the optimum gibberellin concen-tration for enhancing the seed germination and seedling growth of tall fescue under drought stress was 100-200 mg/L.关键词
高羊茅/赤霉素/聚乙二醇(PEG)/种子萌发/缓解效应Key words
tall fescue/gibberellin/PEG/seed germination/alleviating action引用本文复制引用
陈志飞,宋书红,张晓娜,张莹,李欣悦,杨云贵..赤霉素对干旱胁迫下高羊茅萌发及幼苗生长的缓解效应[J].草业学报,2016,25(6):51-61,11.基金项目
国家牧草产业技术体系“优质牧草产品标准化生产关键技术”（CASR-35-01A）和国家燕麦产业技术体系“燕麦加工利用”（CARS-08-D1）资助。 （）
