超氧自由基在三环唑防治稻瘟病中的作用

 研究了三环唑对水稻超氧自由基(O₂^{· -})产生的影响及其在病害防治中的意义,结果表明三环唑能刺激药剂-植物-病菌互作过程中O₂^{· -}的产生。O₂^{· -}清除剂甘露醇和抗坏血酸对稻瘟病菌菌丝生长有一定的抑制作用,于接种后处理却对三环唑表现拮抗作用。外源H₂O₂和O₂^{· -}及从经三环唑预处理并接种的植株获得的叶片泌出液都对稻瘟病菌孢子萌发有直接的抑制作用,且三环唑对这种抑制作用表现明显的增效。说明刺激寄主产生O₂^{· -}和降低病菌的抗氧化能力可能是三环唑防治稻瘟病的作用机制之一

Possible function of superoxide anion radical in rice blast disease control by tricyclazole

Effect of tricyclazole on production of superoxide anion radical (O .- 2) in rice and the possible function of this effect on blast disease control were studied. Results showed that tricyclazole could significantly induce O .- 2 production in rice during chemical plant pathogen interaction. O .- 2 scavengers, mannitol and ascorbic acid, can directly inhibit the mycelium growth rate of Magnaporthe grisea in vitro and have an antagonic effect on tricyclazole when treated after inoculation. Exogenous H 2O 2 and O .- 2 have an inhibitory effect on spore germination of M. grisea , and tricyclazole notably promoted this effect, and so did the diffusates collected from inoculated leaves pre treated with tricyclazole. These suggested that promoting O .- 2 production in host and decreasing anti oxidative capacity of pathogen also are possibl mechanisms of tricyclazole against blast disease.