高温胁迫对孔雀草和万寿菊不同品种生长和生理的影响

以万寿菊属（Tagetes）的6个孔雀草品种和3个万寿菊品种为试材，研究了38℃／21℃（昼／夜）高温胁迫对其株高、根长、根数、干样质量、热害指数以及叶绿素[Chl．（a＋b）]含量、叶片相对电导率（REC）、丙二醛（MDA）含量、叶片相对含水量（RWC）、抗氧化酶（SOD、POD、CAT、APX）活性等指标的影响。结...

Effects of Heat Stress on Growth and Physiology of Marigold Cultivars

The effects of high temperature 38 ℃/21 ℃（day/night）on plant growth，leaf chlorophyll content，relative electric conductivity（REC），malon dialdehyde（MDA）content，relative water content（RWC），the activities of superoxide dismutase（SOD），peroxidase（POD），catalase（CAT）and ascorbate peroxidase（APX）were investigated in 9 marigold cultivars. The results showed that 9 cultivar seedlings showed different degrees of damage symptom under high temperature for 4 days. MDA contents and REC increased significantly，whereas leaf chlorophyll content，RWC and APX decreased under high temperature treatment，which also increased SOD，POD and CAT activities. The path coefficient analysis showed a significantly positive correlation between REC and heat injury index，but significantly negative correlations between SOD，POD and CAT activities and heat injury index. The heat tolerance of the tested 9 cultivars decreased in the order of‘Discovery’，‘Chokdee’，‘Giant’，‘Gate Gold’，‘Great Hero’，‘Janie’，‘Durango’，‘Little Hero’and‘Bonanza’.