旋覆花花序不同溶剂萃取物对植物病原真菌的抑菌活性

Antifungal activities of flower extracts of Inula britannica L. with different solvents

为明确旋覆花的农用杀菌活性,采用液-液分配法对旋覆花乙醇提取浸膏进行萃取分离,并采用离体法和活体组织法测定不同溶剂萃取物对13种植物病原真菌的抑菌活性.结果表明:石油醚、氯仿、乙酸乙酯、正丁醇的萃取率分别为34.89%、8.99%、8.63%和22.72%;在1.0mg·mL-1剂量下,氯仿萃取物对各供试菌菌丝生长均有较强的抑制作用,其中对辣椒疫霉病菌和油菜菌核病菌菌丝生长抑制率分别达73.77%和66.25%,乙酸乙酯萃取物和正丁醇萃取物对辣椒疫霉病菌和油菜菌核病菌菌丝生长也有较好的抑制活性,抑制率分别达67.69%、62.12%和56.07%、51.75%,石油醚萃取物对番茄灰霉病菌菌丝生长抑制率为58.70%;在1.0mg·mL-1剂量下,除苹果斑点落叶病菌外,氯仿萃取物可显著抑制麦冬炭疽病菌、棉花枯萎病菌、板栗炭疽病菌、玉米青枯病菌和辣椒枯萎病菌的孢子萌发,抑制率分别达96.00%、92.44%、80.43%、78.45%和71.84%,乙酸乙酯萃取物对各供试菌孢子萌发抑制率在40.86%～86.42%之间,石油醚萃取物对棉花枯萎病菌孢子萌发抑制率达82.52%;果实针刺法测定结果表明,在2.0mg·mL-1剂量下,氯仿萃取物对番茄灰霉病的治疗效果和保护效果分别为57.65%和50.60%(6d),其中治疗效果与对照药剂0.4mg·mL-1施佳乐无显著差异.

In order to understand the fungicidal activity of Inula britannica,ethanolic extract of its flowers was separated by different solvents and the activities of different solvent extracts against 13 plant pathogenic fungi were tested in vitro and in vivo.The results showed the extraction rates of petroleum ether,chloroform,ethylacetate and n-butyl alcohol were 34.89%,8.99%,8.63% and 22.72%,respectively.Chloroform extract at the concentration of 1.0 mg·mL^-1 exhibited strongly fungicidal activities to mycelium growth of the investigated fungi,and the inhibition rates against Phytophthora capsici and Sclerotinia sclerotiorum were 73.77% and 66.25%;the inhibition rates of the ethylacetate extract and n-butyl alcohol extract against P.capsici and S.sclerotiorum were 67.69%,62.12% and 56.07%,51.75%,respectively;the inhibition rate of the petroleum ether extract against Botrytis cintrea was 58.70%.With the same application rate as above,the chloroform extract could inhibit the spore germination of Colletotrichum dematium,Fusarium oxysporum on the cotton,Colletotrichum gloeosporioides,Fusarium graminearum and Fusarium oxysporum on the capsicum,and the inhibition rates were 96.00%,92.44%,80.43%,78.45% and 71.84%,respectively;the inhibition rates of ethylacetate extract against six investigated fungi were from 40.86% to 86.42%;spore germination was inhibited markedly in F.oxysporum by petroleum ether extract,and the inhibition rate was 82.52%.The protective and therapeutic efficacies of chloroform extract against B.cinerea were 57.65% and 50.60% （6 d） on the tomato treated at the concentration of 2.0 mg·mL^-1,respectively,and its therapeutic efficacy wasn＇t significantly different with the control fungicide-pyrimethanil at 0.4 mg·mL^-1.