水分胁迫下菊苣航天诱变新品系保护酶活性变化

目的]该研究旨在了解航天诱变对菊苣不同品系保护酶活性的影响,为南方喀斯特地区筛选耐旱植物提供科学依据。方法]以‘实践八号’育种卫星搭载选育出的菊苣新品系和目前主推的菊苣品种为研究对象,对SOD活性、POD活性、CAT活性以及丙二醛含量进行测定。结果]随着水分胁迫时间的增加,PA-82、普那菊苣和PA-43的丙二醛含量逐渐升高,在处理12 d时,分别上升了0.575、0.72和0.844μmol/g;SOD、POD和CAT活性迅速升高,在处理9 d时,PA-82、普那菊苣和PA-43的SOD分别上升了878.9、809.2和711.1U/g,上升幅度为139.1%、136.7%和121.1%;POD分别上升了4 397、3 754和2 767 U/（g·min）,上升幅度为265.84%、257.65%和204.06%;CAT分别上升了402.1、277.1和170.9 KU/L,上升幅度为73.08%、39.69%和26.20%;之后3种保护酶均出现大幅度下降,12 d时,PA-82、普那菊苣和PA-43的SOD分别下降1 206.5、1 144.7和1 108.6 U/g,POD分别下降3 145、2 876和2 753 U/（g·min）,CAT分别下降587.2、698.1和584.1 KU/L。结论]经综合评价,3种菊苣的抗旱能力为PA-82〉普那菊苣〉PA-43。

Change in Activities of Protective Enzymes in New Strains of Cichorium intybus L.Mutated in Outer Space under Water Stress

Objective] This study aimed to investigate the effects of space mutation on the activities of protective enzymes in different strains of Cichorium intybus L. and provide theoretical basis for screening drought-tolerant plants in southern karst area. Method] C. intybus seeds were sent into outer space by ＇Shijian No.8＇ seed- breeding satellite. The new strains and original variety of C. intybus L. were used as experimental materials to determine the activities of catalase （CAT）, peroxidase （POD）, superoxide dismutase （SOD）, and malondialdehyde （MDA） content. Result] The results showed that MDA content in PA-82, Puna chicory and PA-43 increased gradually with the increase of water stress duration, which was enhanced by 0.575, 0.72 and 0.844 μmol/g respectively at 12 days. In addition, the activities of SOD, POD and CAT increased rapidly; at 9 days, the activities of SOD in PA-82, Puna chicory and PA-43 were enhanced by 878.9, 809.2 and 711.1 U/g, with the increas- ing range of 139.1%, 136.7% and 121.1%, respectively; the activities of POD were enhanced by 4 397, 3 754 and 2 767 U/（g ·min）, with the increasing range of 265.84%, 257.65% and 204.06%, respectively; the activities of CAT were enhanced by 402.1, 277.1 and 170.9 KU/L, with the increasing range of 73.08%, 39.69% and 26.20%, respectively; subsequently, the activities of these three protective enzymes were reduced significantly; at 12 days, the activities of SOD in PA-82, Puna chicory and PA-43 were reduced to 1206.5, 1144.7 and 1108.6 U/g, respectively; the activi- ties of POD were reduced to 3 145, 2 876 and 2 753 U/（g·min） , respectively; the activities of CAT were reduced to 587.2, 698.1 and 584.1 KU/L, respectively. Con- clusion] According to the results of comprehensive evaluation, drought resistance in three C. intybus varieties exhibited a descending order of PA-82 〉 Puna chicory 〉 PA-43.