月腺大戟根总黄酮对尖孢镰刀菌抑制作用的研究

采用生长速率法和孢子萌发法分别测定月腺大戟根总黄酮对尖孢镰刀菌菌丝生长和分生孢子萌发的抑制率,显微观察总黄酮处理尖孢镰刀菌后菌丝体形态结构的变化,并测定菌丝体相对电导率,菌丝体内超氧化物歧化酶(SOD)、过氧化氢酶(CAT)活性。结果表明:月腺大戟根总黄酮对尖孢镰刀菌菌丝生长和分生孢子萌发均有显著的抑制作用,抑制率随总黄酮浓度增加而增高,20 mg/L时抑制率达100%。总黄酮处理后的尖孢镰刀菌菌丝较细,分支减少,透明度差,液泡数量增多且形成较大的液泡;菌丝体细胞膜透性增加,SOD、CAT活性呈先上升后下降的趋势。以上实验结果可为植物病害生物防治及开发植物源农药方面提供理论依据和实验技术。

The Inhibitory Effects of Total Flavones Extracted from the Roots of Euphorbiae bracteolata Hayata. on Fusarium oxysporum

The inhibitory ratio of total flavones extracted from the roots of Euphorbiae bracteolata Hayata.is determined.on the mycelia growth and spore germination of Fusarium oxysporum by the methods of growth rate and spore germination.Then,the mobility and structure of mycelia were observed under microscope,the penetration and the activity of superoxide dismutase(SOD),catalase(CAT) of mycelia were determined.The results showed that the total flavones extracted from the roots of Euphorbiae bracteolata Hayata.had significantly inhibitive effect on the mycelia growth and spore germination of Fusarium oxysporum.The rate of inhibition rised with the increasing of concentration of total flavones.The rate inhibition was 100 % when the concentration reached 20 mg /L.The mycelia treated became thinner,ramus and transparency decreased,something thick assembled,more vacuole appeared and became bigger.The penetration of membrane increased and the activity of SOD,CAT increased first and decreased later.These results can provide the oretical basis and experimental techniques for the biological control of plant diseases and the development of botanical pesticides.