| Abstrakt: |
Moldy rot on the rubber sting panel decreases the yield and regeneration of its bark. The objective was to identify the causative agent of the disease in San Juan Bautista Tuxtepec, Oaxaca and evaluate its in vitro sensitivity to fungicides. To this end, tissue from the diseased sting panel was collected and made insulations. The isolates were characterized in the nutritive media PDA (papadextrose- agar), CLA (carnation leaves-agar), FLA (liquid fermentation-agar), CDA (coffeedextrose- agar) and ZA (carrot-agar). Growth rates were evaluated and pathogenicity tests were carried out in the laboratory and in the field, as well as in vitro sensitivity to Mancozeb 70%, Benomilo, Carbendazin, Propiconazole, Chlorothalonil, and Carboxamide, in 10 treatments and eight repetitions. The results showed four isolates of the genus Fusarium, which showed polymorphism according to the culture medium, with radial growth and marked rings. Microconidia and macroconidia dispersed in the mycelium and white, orange and blue sporodochs were observed at 36 days. The growth rate varied with the nutrient medium and the inoculated strain. F. circinatum, F. lateririum, F. decemcellulare and F. mangiferae were identified. In the laboratory pathogenicity tests all inoculated strains were positive and in the field only F. circinatum and F. mangiferae. The sensitivity bioassay showed fungicide-dependent response and isolation. These results allow us to conclude that the species F. circinatum, F. mangiferae, F. lateririum and F. decemcellulare can cause moldy rot in the sting panel of clone IAN 710. This is a first report that involves these species. Its control depends on the species of Fusarium and the fungicide used. [ABSTRACT FROM AUTHOR] |
