外源钙对二氯喹啉酸胁迫下烤烟活性氧及保护酶的修复效应

研究了喷施不同浓度CaCl2溶液对二氯喹啉酸胁迫下烤烟活性氧和保护酶的修复效应。结果表明,同正常烟叶相比,二氯喹啉酸胁迫下的烤烟叶片超氧阴离子(O2.-)、羟自由基(.OH)、过氧化氢(H2O2)、丙二醛(MDA)及脯氨酸含量升高,而超氧化物歧化酶(SOD)及过氧化物酶(POD)活性下降;受害烟株喷施外源钙后,烟叶中O2.-、.OH、H2O2、MDA含量降低,SOD、POD活性提高,脯氨酸含量升高,与受害对照相比,喷施10mmol/L外源钙处理20d时,烟叶中O2.-、.OH、H2O2及MDA含量分别降低60%、49%、38%、42%;SOD、POD活性分别提高21%、81%;脯氨酸含量增加77%。喷施外源钙对二氯喹啉酸胁迫下烟叶生长有一定的修复作用,且喷施10mmol/L CaCl2时修复效果最佳。

Repair Effects of Exogenous Calcium on Active Oxygen and the System of Protective Enzymes in Flue-cured Tobacco under Quinclorac Stress

The study was designed to investigate,under quinclorac stress,repair effects of diffe-rent concentrations of exogenous calcium on active oxygen and the system of protective enzymes of flue-cured tobacco.It showed that,under quinclorac stress,the content of superoxide anion radi-cal(O-·2),hydroxyl radical(·OH),hydrogen peroxide(H2O2),malondialdehyde(MDA) and proline increased,and the activity of superoxide dismutase(SOD) and peroxidase(POD) reduced.However,after spraying exogenous calcium,the indicators detected above tended towards a normal level except proline.After spraying 10 mmol/L CaCl2 for 20 days,the content of O-·2,·OH,H2O2 and MDA decreased 60%,48%,38% and 42%,respectively,and the activity of SOD,POD increased 21%,81%,respectively,as well as the content of proline increased 77%.Results suggested that spraying different concentrations of exogenous calcium had a positive repair effect on flue-cured tobacco under quinclorac stress,and the optimal concentration was 10 mmol/L.