11种杀菌剂对甘蔗赤腐病菌的毒力测定

In vitro Inhibitory Effects of 11 Fungicides on Mycelial Growth of Sugarcane Red Rot Pathogen

由镰孢炭疽菌（Colletotrichum falcatum Went.）引起的甘蔗赤腐病是甘蔗上最具毁灭性的病害之一,在病害流行季节能导致严重的产量损失。为了解甘蔗赤腐病原对杀菌剂的敏感性,本研究测定了11种杀菌剂对该病原菌的毒力。结果表明,11种杀菌剂对甘蔗赤腐病菌的毒力存在明显差异。其中,戊唑醇、丙环唑、咪酰胺、苯醚甲环唑、多菌灵等5种药剂对甘蔗赤腐病菌菌丝体生长具有较好的抑制作用,EC50值介于0.227-0.818μg/mL。其对应EC95值也都小于12μg/mL,介于1.416-11.339μg/mL。就敏感性而言,4株赤腐病菌菌株对多菌灵的b值在11种杀菌剂中均为最大。由此表明,甘蔗赤腐病菌对多菌灵的剂量反应变化比其它几种杀菌剂均要敏感。

Abstracts Red rot caused by Colletotrichum falcatum Went is the most devastating problem of sugarcane （Sacchrum officinarium L.） and causes serious yield losses under favorable environmental conditions. In order to understand the pathogen sensitivity to fungicides, and 11 fungicides were tested in vitro for their effectiveness to inhibit to four isolates of C. falc atum. The results indicated that different fungicides exhibited diverse toxicities, and the most effective in v itro proved to be the fungicides containing tebuconazole, propiconazole, prochloraz, difenoconazole and carbendazim. Their EC50 and EC95 values for inhibition of the isolates ranged from 0.227μg/mL to 0.818 μg/mL and 1.416 μg/mL to 11.339 μg/mL, respectively. The in v itro sensitivity of C. falc atum to 11 fungicides was also examined. The results showed that the b values from carbendazim were the highest among the 11 fungicides with respect to different isolates. These results indicate that the sugarcane red rot pathogen is more sensitive to carbendazim than other fungicides tested.