Efficacy of chemical fungicides against the anthracnose disease caused by Colletotrichum gloeosporioides in Carica papaya fruits

Resumen

Objective: To evaluate the efficacy of chemical fungicides against Colletotrichum gloeosporioides in papaya fruits.

Design/methodology/approach: The effect of four chemical fungicides (A+F=azoxystrobin + fludioxinil, C+F=cypronil + fludioxinil, B+P=boscalid + pyraclostrobin and T=tiabendazole) at 250, 500, 750, and 1000 mg kg^-1 were assessed on severity and the area under the disease progress curve (AUDPC) of Colletotrichum gloeosporioides inoculated on papaya fruits.

Results: At 12 days after inoculation (dai) A+F achieved a range of effectiveness between 63.0 (250 mg kg^-1) to 77.52 (1000 mg kg^-1); while the range of effectiveness for T was 12.8% (250 mg kg^-1) to 74% (1000 mg kg^-1). Both fungicides achieved the highest effectiveness at 1000 mg kg^-1 that C+F (38.5%) and B+P (55.6%). The AUDPC achieved the same value at the four studied concentration in A+F, C+F, and B+P. Only 750 and 1000 mg kg^-1 of T achieved the lowest AUDPC than 250 and 500 mg kg^-1.

Findings/conclusions: The fungicides A+F and T achieved adequate control of anthracnose in papaya fruits and the use of the diagrammatic logarithmic scale is easy to use to give a quick estimate of the disease, as well as being easy to reproduce.