土壤含水量对半夏生长和抗氧化性的影响

在土壤含水量为田间最大持水量的85%（高水）、70%（对照）和55%（中度干旱）的条件下,研究半夏的生长、丙二醛（MDA）含量及超氧化物歧化酶（SOD）、过氧化物酶（POD）和过氧化氢酶（CAT）活性的动态变化.结果表明,中度干旱抑制了半夏株高、叶长和叶宽的生长.MDA含量和3种保护酶活性的变化趋势为MDA和CAT先降后升,而SOD表现为先升而后降,但POD一直呈现上升的变化动态.土壤中度干旱下的半夏叶片中MDA含量和保护酶活性均高于对照,其差异达到了显著水平（P＜0.05）.在清除活性氧的过程中,CAT的作用不明显,SOD和POD协同起作用,且SOD活性与MDA含量呈负相关,相关不显著.

Effects of Soil Water Content on the Growth and Antioxidant Capability in Pinellia ternata(Thunb.) Breit

The growth,MDA content and dynamic variations of SOD,POD,CAT activity were studied under the condition that Pinellia ternata(Thunb.) Breit were treated with three levels of soil relative water content which were respectively 85%(high water),70%(control) and 55%(moderate drought).The results showed that the growth of Pinellia ternata(Thunb.) Breit was restrained under moderate drought.MDA content and CAT activity declined firstly and then increased,while SOD activity increased to a certain level and declined finally and POD activity increased at all times.But MDA content and three enzyme activity of seedlings treated by moderate drought were highest among three treatments and significantly different compared to control(P<0.05).In reducing active oxygen,SOD and POD together played a significant effect while CAT contributed little.And there was negative correlation between SOD activity and MDA content but no siginificant.