DOI: 10.36347/sjavs.2022.v09i11.006

Pages: 189-195

The main phytosanitary problem of commercial bananas is black Sigatoka, caused by the fungus Mycosphaerella fijiensis Morelet. This pathogen causes loss of leaf area, loss of exportable quality and low crop yields. The objective of the research was to evaluate four systemic fungicides applied in mixtures in different combinations and to determine percentages of severity, total leaves, and old leaf free of streaks in the two zones established for data collection. This work was carried out in Rivas, Nicaragua, municipality of Potosí, in the farms El Trapiche, El Espíritu and La Granja. In an area of 5 ha-1 of the cultivar CEMSA ¾, 50 plants were selected in the border zone and 50 in the center, with four treatments: T1 (Triazole + Amine), T2 (Pyrimethanil + Spiroxamine), T3 (Difenoconazole + Amine), T4 (Amine + Pyrimethanil) each with three replications, the frequency of application was 14 days, disease severity was recorded in percentage using the Stover scale on leaves 3, 4 and 5. The experimental design was randomized blocks and the data were analyzed using a two-way ANOVA. It was determined that the percent severity on leaf 4 in the center and border zone was High (> 30 and < 50%) and on leaf 5 in both zones was severe (> 60 to 70%) in all farms. The T4 fungicide mixture (amine + pyrithamethanil) had the lowest percentages of black Sigatoka severity, the best average number of old leaves free of streaks and the highest number of total leaves.