干旱胁迫对白菜型冬油菜苗期生理特性的影响

Effect of Drought Stress on Physiological Character of Winter Rape(Brassica campestris L.)at Seedling Stage

对8个白菜型冬油菜品种苗期抗旱胁迫下生理指标的变化特性进行研究,了解不同生理指标与白菜型冬油菜品种耐旱性的相关性,筛选耐旱品种或种质。结果表明,干旱胁迫后,油菜游离脯氨酸(Pro)、超氧化物岐化酶(SOD)、过氧化物酶(POD)和过氧化氢酶(CAT)活性都逐渐增加,丙二醛(MDA)质量分数先降低后增加。MDA与苗期干旱胁迫后幼苗成活率呈极显著相关,POD与幼苗成活率呈显著相关,可作为鉴定白菜型冬油菜抗旱性鉴定的首选指标。综合来看,8个品种中天油7号对干旱反应敏感,表现为不抗旱;陇油7号对干旱反应迟钝,为强抗旱品种;天油2号、陇油9号、天油5号为弱耐旱抗品种,陇油6号、陇油8号、天油8号为中抗旱品种。

To learn the drought resistance mechanism and find some new materials for drought resist- ance breeding of winter rapeseed, the paper studied the physiological character at seedling stage under drought stress. The results showed that Pro, S（）D, POD and CAT activity increased after drought stress while MDA content decreased first and then increased. MDA content is highly significant corre- lation with survival rate and POD activity is significant, so MDA content would be the first choice to evaluate drought resistance of winter rapeseed. Tianyou 7 is sensitive to drought stress and has no drought resistance. Longyou 7 is obtuse to drought stress and labeled as high drought resistant varie ty. Tianyou 2, Longyou 9 and Tianyou 5 are low drought resistant varieties. Longyou 6, Longyou 8 and Tianyou 8 are medium resistant varieties.