6种杀菌剂对兰花枯萎病菌抑制作用比较

为筛选防治兰花枯萎病的有效药剂,采用菌落直径法和孢子萌发法测定并比较了6种杀菌剂对兰花枯萎病菌的室内抗菌活性。结果表明:新型杀菌剂啶菌恶唑对病菌菌丝生长的抑制活性最高,同时对病菌孢子萌发也有较高活性;三唑类杀菌剂苯醚甲环唑对病菌菌丝生长抑制活性较高,但对病菌孢子萌发抑制活性最低;二甲酰亚胺类杀菌剂腐霉利对病菌菌丝生长和孢子萌发都有一定的抑制作用,但该药对菌丝生长的抑制作用有限,其EC90值明显低于啶菌恶唑和苯醚甲环唑;甲氧基丙烯酸酯类杀菌剂啶氧菌酯在离体条件下对菌丝的抑制活性较低,但其对孢子萌发有较高活性;有机硫杀菌剂代森锰锌对病菌孢子萌发的抑制活性最高,但对菌丝生长的抑制活性很低;苯并咪唑类杀菌剂甲基托布津对孢子萌发有一定的抑制活性,但对菌丝生长的抑制活性很低。试验结果可以为兰花枯萎病的田间防治提供有益参考。

Comparison of Inhibition of Six Fungicides against Fusarium oxysporum f.sp.Cattleyae

Laboratory antifungal activity of six fungicides to Fusarium oxysporum f.sp.Cattleyae was determined by the methods of mycelium growth inhibition and spore germination.The results showed that the novel fungicide SYP-Z048 had the highest activity on mycelial growth and relatively high activity on spore germination.The triazole fungicide difenoconazole had very high effect on mycelial growth but with the lowest effect on spore germination among these fungicides.Dicarboximides procymidone was effective on both mycelial growth and spore germination,but had limit inhibitory activity on mycelial growth because of it’s significantly lower EC90 value than SYP-Z048 and difenoconazole.Strobilurin fungicides picoxystrobin was effect on spore germination but with low effect on mycelial growth in vitro.Organosulfur fungicide mancozeb had the highest activity on spore germination among these fungicides while with very low activity on mycelial growth.The benzimidazole fungicide thiophanate-methyl had some activity on spore germination,but with very low activity on mycelial growth.These results provide a beneficial reference for control of orchid wilt pathogen.