叶水势、丙二醛含量及保护酶活性与桃砧木抗旱性的关系

以抗旱的长柄扁桃、抗旱中等的毛樱桃和抗旱差的光核桃苗为试材，研究水分胁迫条件下3种桃砧木叶水势、叶片丙二醛含量和保护酶活性的变化与抗旱性的关系。结果表明，干旱导致叶水势降低，水势与土壤含水量呈显著正相关，抗旱强的砧木叶水势降低速度慢；干旱造成3种桃砧木MDA含量上升，抗旱弱的砧木MDA积累速度快，膜脂过氧化严重；干旱初期抗旱强的砧木SOD活性显著上升，抗旱差的光核桃SOD活性则明显下降；不抗旱的光核桃POD活性的大幅度上升可能是一种伤害反应；CAT在不同的抗旱性砧木中所起的作用不同。

Relations among Water Potential, MDA, Protective Enzymes Activities and Drought-resistance of Peach Rootstocks

Three peach rootstocks(Prunus mira;Prunus tomentosa.;Prunus pedunculata) were treated under soil gradual drought stress.The relations among water potential,MDA,protective enzymes activities and drought-resistance were observed.The result showed that the water potential of three rootstocks decreased with reduction of soil water content and had significantly positive correlation with soil relative water content.the water potential of drought-resistant rootstock reduced slowly.Drought treatment increased MDA content and the MDA content of drought-sensitive rootstock accumulated faster.SOD activity of drought-resistant rootstock increased significantly in initial stages of drought.Meanwhile,SOD activity of drought-sensitive rootstock decreased.It was a damage response for increasing POD activity in Prunus mira.CAT activity had the different effects in different drought-resistant peach rootstocks.