甘薯紫纹羽病病原菌的生物学特性及室内药剂筛选研究

Biological Characteristics of Helicobasidium mompa Tanaka and Selection of Fungicides in Laboratory

对甘薯紫纹羽病(Helicobasidium mompa Tanaka)进行了生物学特性研究。结果表明,适宜该病原菌生长的碳源为淀粉,氮源为硝酸钾,pH为10,菌落直径分别为9.50,8.04,7.52 cm,菌丝在光照、黑暗、光暗交替下均能生长,其中在黑暗条件下生长最好,菌落直径为7.54 cm,菌丝致死温度为50℃、10 min。采用菌丝生长速率法进行了5种杀菌剂对甘薯紫纹羽病菌的毒力测定。结果表明,供试5种杀菌剂对甘薯紫纹羽病菌菌丝生长具有较好的抑制效果,其中97.6%甲基立枯磷和97%氟酰胺效果最佳,EC50值分别为0.28和0.45;87.6%拌种灵的抑制作用其次,EC50值为5.50;96.3%苯醚甲环唑和97%甲基托布津抑制作用相对较差,EC50值分别为17.32和19.12。

Helicobasidium mompa Tanaka is a fungal disease.The biological characteristics of Helicobasidium mompa Tanaka was studied.The results showed that the suitable carbonsource was starch,the suitable nitrogen source was potassium nitrate,and the suitable pH was 7,with colony diameter of 9.50,8.04 and 7.52 cm in the three conditions,respectively.Mycelium could grow in brightness,darkness,and alternating light-dark,best in darkness.The lethal temperature of mycelium was 50 ℃,10 min.The toxicity of five fungicides to Helicobasidium mompa Tanaka was tested by mycelia growth inhibition.The result showed that all 5 fungicides inhibited mycelia growth of Helicobasidium mompa Tanaka.Among the 5 fungicides tested,the highest inhibition effect to mycelia growth of Helicobasidium mompa Tanaka was observed with 97.6 % tolclofos-methyl and the value of EC50 was 0.28;Secondly was 97 % Flutolanil.The effects of 87.6 % Seedavay and 96.3 % difenoconazole were less and the values of EC50 were 0.45,5.50 and 17.32,respectively;97% Topsin-M had the lowest effect and the value of EC50 was 19.12.