Uso de produtos naturais no controle de antracnose causado por Colletotrichum gloeosporioides em mamão

Abstract

One of the limiting factors in papaya production and commercialization is its vulnerability to a large quantity of diseases. Anthracnose, caused by Colletotrichum gloeosporioides, is responsible for major losses in this culture and is considered a disease of high economic importance. Seeking an alternative control, the effect of the natural products Acadian®, Biopirol®, Trichodermil®, Rocksil®and Protego FL® was evaluated in vitro and in vivo. The in vitro assay was conducted in a completely randomized design with five products and two concentrations. For each experiment, four replicates were used and each replicate was represented by a Petri dish of 9 mm. For the in vivo evaluation, a completely randomized design was used, in factorial arrangement, with 5 inducers x 2 concentrations x 2 application times and 4 replicates per treatment, and each replicate was represented by one papaya fruit. The bioinducers and abiotic inducers were applied at 48 and 72 hours, to separate treatments, before pathogen inoculation. The same dosages were used for treatments in vitro and in vivo. According to the results obtained in the in vitro experiment, all used products inhibited C. gloeosporioides growth at six days of growth, highlighting Biopirol® 40 and 60 mL/L and Rocksil® 15 and 30 mL/L at both used concentrations and Protego FL® at the highest concentration 6 g/L, which completely inhibited fungal growth. For the in vivo test, the used inducers were effective in reducing infections caused by C. gloeosporioides. Biopirol® 40 mL/L differed from control, showing smaller anthracnose lesions, compared to the other treatments at the first application time (48h). Regarding the results obtained in the second time of application (72h), Acadian® 40 mL/L and Rocksil® 30 g/L showed better results with lower averages of anthracnose lesions, when compared to the other treatments at this same time. These results demonstrate that the used products were capable of decreasing the aggressiveness of anthracnose in papaya fruits, were efficient in the management of diseases and can become important compounds in the management of post-harvest anthracnose.