多花黑麦草对水涝胁迫的生理响应

采用盆栽法,研究在不同水涝胁迫条件下,2个多花黑麦草品种‘Maximus’和‘Hercules’的生理生化抗性表现。结果表明：在轻度水涝胁迫条件下（水位与土层平齐）,脯氨酸含量‘Maximus’比对照上升225.6%、‘Hercules’比对照上升509.7%,其他指标与对照组相比差异不显著（P〉0.05）;在重度水涝条件下（水位在土层上4cm）,2个品种叶片中叶绿素含量‘Maximus’比对照下降23.5%、‘Hercules’下降63.5%;丙二醛含量‘Maximus’比对照上升48.9%、‘Hercules’上升76.2%;脯氨酸含量‘Maximus’增加405.9%、‘Hercules’增加531.8%;过氧化物酶活性分别上升204.0%和74.1%,与对照组相比差异显著（P〈0.05）,超氧化物歧化酶和过氧化氢酶活性均表现为先升后降。在轻度水涝胁迫时,各个指标变化不显著或从处理第7d开始变化显著;在重度水涝胁迫4d后各个指标开始剧烈变化。因此认为多花黑麦草在轻度水涝时可正常生长7d,在重度水涝时可正常生长4d。

Physiologic Responses of Ryegrass Lolium multiflorum Against Waterlogging Stress

Two Italian Ryegrass varieties （ ‘ Maximus＇ and ‘ Hercules＇） were studied with pot-culture experiment in physiological and biochemical responses against waterlogging. The results showed that： with mild stress of waterlogging （water just covering soil）, the proline content of ‘Maximus＇ and ‘Hercules＇ was increased by 225.6% and 509.7%, respectively, compared with control group although other compound indices observed no significant differences （P 〉 0. 05）. Under severe waterlogging （submerged soil for 4 cm）, the significant physiochemical changes were observed while compared with control group （P〈0.05） in the chlorophyll content in leaves of ‘Maximus＇ and ‘Hercules＇ decreased about 23.5% and 63.5%, respectively; the proline content of ＇ Maximus＇ and ＇ Hercules＇ increased by 405.9 % and 513.8 %, and the MDA content of both varieties increased by 48. 9 % and 76.2%, respectively; the peroxidase activity of ‘ Maximus＇ and ‘ Hercules＇ was increased by 204.0% and 74.1%, respectively, while superoxide dismutase and catalase activity were increased first and then decreased. With water slight covering, there was no significant change in plant physiology observed until the 7th day of waterlogging, while by deepwater submergence, the physiochemical responses started at the 4th day of treatment. The results suggested that the ryegrass could grow normally for 7 days under the mild submergence but only for 4 days whenever submerged with deepwater.