野牛草克隆分株酶促活性氧清除系统对差异光周期的响应

The Response of Enzymatic Active Oxygen Scavenging System in Leaves of Buchloe dactyloides to Differences Photoperiod

以盆栽野牛草克隆分株为材料,将克隆分株分别标记为O(姊株)和Y(妹株),设置连接组和断开组两种处理,其中,连接组中O分株和Y分株通过节间子相连,断开组则剪断分株节间子;两组处理的O分株光周期均设置为光照12h/黑暗12h,Y分株光周期均设置为黑暗12h/12h光照(恰好与O分株相反),经过7d的差异光周期处理后进行72h全光照稳定培养,并于全光照条件下在48h内连续测定各分株叶片超氧化物歧化酶(SOD),过氧化物酶(POD),过氧化氢酶(CAT),抗坏血酸过氧化物酶(APX)的活性以及丙二醛(MDA)的含量,探讨野牛草叶片酶促活性氧清除系统对差异光周期的响应特征。结果表明,差异光周期处理1周后,全光照条件下,断开状态的野牛草克隆分株O和Y间叶片中SOD、POD、CAT、APX活性以及MDA含量在24h内基本呈现相反的变化趋势,而野牛草相连克隆分株O和Y间叶片中以上指标在24h内呈现趋于一致的变化规律。研究发现,野牛草酶促活性氧清除系统活性在一天内呈现节律性表达模式,且差异光周期处理下的野牛草相连克隆分株的活性氧清除系统的活性的节律性变化趋于同步。

We used Buchloe dactyloides.ramets as materials to research physiological metabolic response of B.dactyloides.leaves active oxygen scavenging system to differences photoperiod response.Clonal ramets were labeled as O （old sister ramet） and Y （young sister ramet）,then we set connective group and disconnected group.O ramet and Y ramet were connected through the internode in connective group,whereas the internodes were cut off in disconnected group;the light cycle of O ramet was set for light 12 h/dark 12 h in both two groups,instead,light cycle of Y ramet was set for 12 h darkness/12 h light （just opposite to O ramet）.And the activities of superoxide dismutase （SOD）,peroxidase （POD）,catalase （CAT）,ascorbate peroxidase （APX）,and malondialdehyde （MDA） content of ramet leaves were continuous measured 48 h illumination after cultivation of 7 d differences photoperiod treatment and 72 h stable illumination conditions.The results showed that after one weeks of different photoperiod treatments,under continuous light conditions,SOD,POD,CAT,APX activities and MDA content in disconnected ramets of B.dactyloides.leaves basically showed the opposite variation trend within 24 h.However,SOD,POD,CAT,APX activities and MDA content in connected ramets of B.dactyloides.leaves presented convergence of variation trend within 24 h.It indicated that reactive oxygen species scavenging system of B.dactyloides.showed rhythmic expression patterns,and B.dactyloides.connected ramets reactive oxygen species scavenging system tends to be synchronized under different photoperiod treatments.