Natural resistance of two mango Mangifera indica L. commercial cultivars to anthracnose caused by Colletotrichum gloeosporioides Penz. Penz. & Sacc

Mexico ranks first worldwide as the largest mango exporter is one of the more produced tropical fruits worldwide. The need for strategies for the protection of crops, environment and people leads us to investigate disease control methods. The use of resistant cultivars is the most important. In addition, it is advantageous for the producer because it will reduce the cost for disease control. The objective of this research was to evaluate the natural resistance of two mango cultivars against anthracnose, using different spore doses and times of evaluation. The sampling was performed on April 15th, 2018 at an open market placed south of Saltillo, Coahuila, Mexico. Pathogen was isolated from fruits of Tommy Atkins and Ataulfo mango cultivars showing advanced degrees of black spots collected out from at open markets in Saltillo, Coahuila, Mexico. The pathogen purification was done by monoconidial cultures and identification was done with morphocultural criteria. Spore suspension was prepared and inoculated on ripe mango fruits using different doses and disease severity was evaluated 6 and 10 days after inoculation using millimetric sheets. A complete random factorial design of three factors was used, where: factor A stands for mango cultivars (Tommy Atkins and Ataulfo), factor B is treatments and factor C stands for times of evaluation. The results are shown as percentage and data was analyzed with factorial analysis using the SAS® 9.1 software. C. gloeosporioides was identified in mango cultivars; with hyaline conidia of 16.90 to 25.12 µm length and 4.33 to 5.18 µm width. The results show cultivars resistant to anthracnose in the study area. Natural resistance against anthracnose was as 80.00 to 93.67 %, thus, mango cultivars showed a certain resistant degree