二硫氰基甲烷对水稻恶苗病菌菌体作用机理研究

 有机硫氰化合物二硫氰基甲烷(TH-88,浸种灵)可抑制水稻恶苗病菌(Fusarium moniliforme)对多菌灵(carbendazim)的抗性菌株和敏感菌株,EC50在0.393 3~1.641 2 μ g/ml之间,对菌丝和分生孢子的形态没有影响;该药剂(浓度为1 μ g/ml)对菌体的生物膜(透性)有一定抑制作用;用药剂处理萌芽期、非萌芽期的分生孢子及其初形成的菌丝,结果表明:药剂对菌丝和分生孢子的呼吸作用有影响,以分生孢子萌芽期最为敏感,用二硫氰基甲烷2 μ g/m l处理刚萌芽的分生孢子5 m in,呼吸作用比对照低64.15%;处理NADH细胞色素还原酶和NADH细胞色素氧化酶,前者没有影响,但对后者有54.32%的抑制。用二硫氰基甲烷(1 μ g/ml)处理啤酒酵母(Saccharomyces cerevisiae)的线粒体,呼吸控制速率(RCR)比对照低27.67%;磷氧比(P/O)比对照低9.3%。

The mechanism of organic thiocyanic chemicals: methylene dithiocyanate to Fusarium moniliforme microbes

Organic thiocyanic chemicals, methylene dithiocyanate (TH-88, chemical formula:SCN-(CH₂)₂-SCN) can control rice "Bakanane" disease caused by Fusarium moniliforme, both carbendazim -resistant and -sensitive strains. The EC 50 of TH-88 varies from 0.393 3 to 1.641 2 μg/ml. Biochemically, this chemical increases mycelium seepage with no effect on mycelium and conidium at the concentration of 1 μg/ml, but decreasing the respiration of mycelium and conidium of F. moniliforme, especially during the period of conidium germination with the decrease of 64.15% compared with CK 5 minutes after treatment at the concentration of 2 μg/ml. Methylene dithiocyanate doesn't inhibit the activity of NADH cytochrome C reductase, while it decreases 54.32% of NADH cytochrome terminal oxidase activity at the concentration of 2 μg/ml. Respiration control rate and the rate of P/O are 27.67% and 9.3% lower than CK, respectively, when the mitochondria of beer yeast (Saccharomyces cerevisiae) was treated at the concentration of 1 μg/ml. More