补骨脂种子提取物对水稻纹枯病菌生物活性测定

旨在探究补骨脂种子提取物对水稻纹枯病菌的作用活性。采用菌丝生长和菌核萌发抑制率法、扫描电镜观察、盆栽试验等手段对补骨脂提取物的抑菌活性进行研究并通过田间试验验证。补骨脂种子提取物对水稻纹枯病菌菌丝生长抑制作用的EC₅₀为30.8159 mg/L,当浓度为810 mg/L时对菌核萌发的抑制率为43.33%,扫描电镜下补骨脂提取物作用5天后的水稻纹枯病菌菌丝体排列及形态均有明显变化。盆栽试验结果显示0.2%苯丙烯菌酮微乳剂150倍液对水稻纹枯病的预防和治疗效果分别为94%、78.46%;田间试验表明,按90 g/hm²剂量于水稻分蘖期、孕穗期和齐穗期施药3次后的防效为72.22%。补骨脂种子提取物可抑制纹枯菌丝生长、菌核萌发、破坏其形态结构,其微乳剂对水稻纹枯病具有较好的防治效果。

Psoralea corylifolia L. Extract: Effect on Biological Activity of Rice Sheath Blight

The purpose is to investigate the activity of Psoralea corylifolia L. extract on rice sheath blight. We studied the inhibition effects of Psoralea corylifolia L. extract against rice sheath blight by the hypha growth inhibition test, asclerotia germination inhibition test, SEM technologies and potted plant test, and verified the results by field trials. The results showed that EC₅₀ value of the inhibition effect of Psoralea corylifolia L. extract on mycelium growth of rice sheath blight was 30.8159 mg/L, the inhibition rate to sclerotium germination was 43.33% at 810 mg/L. SEM observation showed that hypha arrangement and morphology changed significantly after being treated by Psoralea corylifolia L. extract for 5 days. The results of potted plant test showed that the preventive and control effect of 150 times diluted 0.2% microemulsion against rice sheath blight was 94% and 78.46%, respectively; the field trials showed that the control effect of 0.2% microemulsion was 72.22% at 90 g/hm² after dosing once at intillering stage, booting stage and full heading stage, respectively. Psoralea corylifolia L. extract can inhibit mycelial growth and sclerotic germination of rice sheath blight, destroy its morphological structure, its microemulsion has remarkable control efficiency on rice sheath blight.