水分胁迫下喷施乙烯利和甲基环丙烯对甘蔗苗期叶片抗氧化酶活性的影响

[目的]研究乙烯利和甲基环丙烯（1-MCP）对甘蔗苗期叶片抗氧化酶活性的影响,为明确乙烯利和1-MCP对甘蔗苗期抗旱能力的影响提供依据.[方法]以桶栽的苗期新台糖22号为研究对象,在不同水分胁迫条件下分别用浓度为200和300 mg/L的乙烯利喷施甘蔗叶面,然后用1 mg/L 1-MCP密闭连续熏蒸16h,在不同处理时期分别测定甘蔗苗期叶片过氧化物酶（POD）、超氧化物歧化酶（SOD）和过氧化氢酶（CAT）活性.[结果]随水分胁迫程度的增强,喷施200mg/L乙烯利＋1 mg/L 1-MCP处理的苗期甘蔗叶片POD、SOD和CAT活性明显增加.而喷施300 mg/L乙烯利＋1mg/L1-MCP处理的甘蔗苗期叶片POD、SOD和CAT活性则呈先升高后降低的趋势,表现为在轻度水分胁迫时呈上升趋势,中度和重度水分胁迫时呈下降趋势.[结论]喷施200 mg/L乙烯利＋1 mg/L 1-MCP能增加苗期甘蔗的POD、SOD和CAT活性,有利于提高苗期甘蔗的抗旱性;但在中度和重度水分胁迫下喷施较高浓度的乙烯利（300 mg/L）和1-MCP不利于提高苗期甘蔗的抗旱性.

Effect of ethephon and 1-MCP under water stress on antioxidase activities of sugarcane leaves at seedling stage

[Objective]The effect of antioxidase activity of sugarcane leaves treated with ethephon and 1-MCP was studied under water stress in sugarcane seedling period to provide references for identifying the influence of ethephon and 1-MCP on drought-resistance of sugarcane seedling. [Method]Antioxidase activity of sugarcane ROC 22 planted in pot was studied by spraying ethephon （200 and 300 mg/L） to sugarcane leaf and enclosed steaming by 1-MCP （1 mg/L） for 16 hours. Finally, the antioxidase activity of POD, SOD and CAT was measured at different stages. [Result ]With the increasing of water stress, the antioxidase activity of POD, SOD and CAT of sugarcane treated with 200 mg/L ethephon and 1-MCP increased markedly, and the antioxidase activity of sugarcane ascended first un- der mild water stress and descended at last under medium or serious water stress. Using 300 mg/L ethephon and 1- MCP is instrumental in improving antioxidase activity of sugarcane under conditions of water stress mildly. But it was unfavorable for improving antioxidase activity of sugarcane to treat with 300 mg/L ethephon and 1-MCP under moder- ate and severe water stress conditions. [ Conclusion ]The antioxidase activity of POD, SOD and CAT of sugarcane can be improved by using 200 mg/L ethephon and 1-MCP, which is beneficial for increasing drought-resistance, howev- er 300 mg/L ethephon and 1-MCP undermines the drought-resistance of sugarcane.