Sensitivity Test of Colletotrichum gloeosporioides and Colletotrichum acutatum Isolated from Rubber to the Fungicides

Colletotrichum leaf fall of rubber tree is becoming an increasingly important disease in Yunnan province.Sensitivity test was carried out in laboratory to screen the effective fungicides to Colletotrichum gloeosporioides and Colletotrichum acutatum isolated from rubber in Yunnan.Prochloraz,carbendazim,thiophanate-methyl,bromothalonil,dacotech and mancozeb were tested by using the mycelial linear growth rate method.The results showed that C.gloeosporioides isolates tested were extremely sensitive to prochloraz,carbendazim,thiophanate-methyl with EC50 of 0.020 9 μg/mL,0.050 5 μg/mL and 0.404 3 μg/mL,respectively.C.acutatum isolates were sensitive to prochloraz,carbendazim,thiophanate-methyl with EC50 of 0.029 0 μg/mL,0.194 6 μg/mL and 3.834 7 μg/mL,respectively.But the sensitivtivity of C.acutatum was lower than that of the former,and mancozeb had a low inhibition to both fungi.