Ramadwa Thanyani Emelton, Makhubu Fikile Nelly, Eloff Jacobus Nicolaas
Department of Life and Consumer Sciences, College of Agriculture and Environmental Sciences, Florida Campus, University of South Africa, Private Bag X6, Florida, 1710, South Africa.
Department of Agriculture and Animal Health, College of Agriculture and Environmental Sciences, Florida Campus, University of South Africa, Private Bag X6, Florida, 1710, South Africa.
Heliyon. 2024 Mar 30;10(7):e28920. doi: 10.1016/j.heliyon.2024.e28920. eCollection 2024 Apr 15.
Phytopathogenic fungi and nematodes cause great losses in economically important crops and food production especially in developing countries. To minimize the use of fungicides and nematicides, researchers have concentrated on the use of natural products for crop disease prevention or control. The aim of the study was to investigate the antifungal activity of leaf extracts, fractions, and isolated compounds (obliquumol and a mixture of lupeol and β-amyrin) and nematocidal activity of fractions (hexane, chloroform and 30% water in methanol and the isolated compounds) on . Nine phytopathogenic fungi (. . . . and ) were used for testing and nematocidal activity was determined on motility of plant parasitic nematode race 2 juveniles Serial microdilution test was utilized to determine the minimum inhibitory concentration (MIC) of each sample against the fungus. Motility tests was done on the second-stage juveniles (J2s) of . The most susceptible phytopathogenic fungal species to the acetone crude leaf extracts were and with MIC of 80 μg/ml which is considered pharmacological significant. was the most susceptible fungus against obliquumol and, lupeol and β-amyrin mixture with MIC values of 8 μg/ml and 16 μg/ml respectively. Lupeol & β-amyrin mixture had good activity on juvenile motility at high concentrations used which was significantly high ( ≤ 0.05) after 24 h, further incubation resulted in temporary paralysis at lower concentrations. Fractions and obliquumol showed good activity after 48 h, stable paralysis was observed up to 72 h. The extracts and isolated compounds may be useful as fungicides if the results can be confirmed under field conditions at levels not toxic to beneficial soil organisms.
植物病原真菌和线虫给经济上重要的作物和粮食生产造成了巨大损失，尤其是在发展中国家。为了尽量减少杀真菌剂和杀线虫剂的使用，研究人员专注于使用天然产物来预防或控制作物病害。该研究的目的是调查叶提取物、馏分和分离化合物（斜卧豆醇以及羽扇豆醇和β-香树脂醇的混合物）的抗真菌活性，以及馏分（己烷、氯仿和30%甲醇水溶液）和分离化合物对线虫的杀线虫活性。使用了9种植物病原真菌（……和……）进行测试，并测定了植物寄生线虫2号小种幼虫活动能力的杀线虫活性。采用系列微量稀释试验来确定每个样品对真菌的最低抑菌浓度（MIC）。对……的二期幼虫进行了活动能力测试。对丙酮粗叶提取物最敏感的植物病原真菌是……和……，其MIC为80μg/ml，这被认为具有药理学意义。……是对斜卧豆醇以及羽扇豆醇和β-香树脂醇混合物最敏感的真菌，其MIC值分别为8μg/ml和16μg/ml。羽扇豆醇和β-香树脂醇混合物在高浓度使用时对幼虫活动能力具有良好活性，24小时后显著较高（P≤0.05），进一步孵育在较低浓度下导致暂时麻痹。馏分和斜卧豆醇在48小时后显示出良好活性，直至72小时观察到稳定麻痹。如果在田间条件下能在对有益土壤生物无毒的水平上证实结果，提取物和分离化合物可能可用作杀真菌剂。
