木醋液对植物病原真菌呼吸作用的影响

Effect of Wood Vinegar on Respiration of Plant Pathogenic Fungi

为探究木醋液在植物病害生物防治中的实际应用及对其病原真菌呼吸作用的影响,试验采用菌丝生长速率法测定其对7种植物病原真菌的抑菌活性,并研究其对供试敏感菌株黄色镰刀菌(Fusariumculmorum)的菌体三羧酸循环关键酶和能量代谢的影响。结果表明,木醋液对7种供试植物病原真菌均有一定的抑制效果,其中对供试敏感菌株黄色镰刀菌的抑菌作用表现最为显著,其EC50值为4.98μL/mL,在浓度5.5μL/mL时,木醋液对其孢子萌发和生物量抑制率分别达90.09%和95.22%;经木醋液处理后,黄色镰刀菌的呼吸速率受到抑制,琥珀酸脱氢酶和苹果酸脱氢酶活性降低,三磷酸腺苷含量降低,二磷酸腺苷和磷酸腺苷含量先升高后降低,能荷水平降低,表明木醋液抑制了黄色镰刀菌的呼吸代谢,阻碍了三羧酸循环的正常运行,干扰了其能量代谢,导致菌体细胞功能紊乱。初步探明,木醋液主要是通过破坏菌体呼吸代谢来实现其抑菌效果。

To explore practical application of wood vinegar in biological control of plant diseases and its impact on respiratory function of pathogenic fungi,experiment used mycelial growth rate method to determine its antibacterial activity against 7 plant pathogenic fungi,and studied its impact on key enzymes of tricarboxylic acid cycle and energy metabolism of sensitive strain Fusarium culmorum tested.Results showed that wood vinegar had a certain inhibitory effect on 7 kinds of plant pathogenic fungi tested,among which Fusarium culmorum,a sensitive strain,showed the most significant inhibitory effect.Its EC50 value was 4.98μL/mL,and when con-centration was 5.5μL/mL,inhibition rates of spore germination and biomass by wood vinegar were 90.09%and 95.22%,respectively.After wood vinegar treatment,respiration rate of Fusarium culmorum was inhibited,activities of SDH and MDH de-creased,content of ATP decreased,ADP and AMP increased first and then decreased,and energy charge level decreased,indicating that wood vinegar inhibited respiration and metabolism of Fusarium culmorum.It hindered normal operation of tricarboxylic acid cycle,interfered with its energy metabolism,and led to dysfunction of fungal somatic cells.It has been preliminarily proved that wood vinegar ccould achieve its antifungal effect mainly by destroying respiration and metabolism of fungi.