Abstract

Chemical treatment is known to effectively eradicate or at least reduce the presence of fungi in seeds. However, this treatment should not impair seed quality. The purpose of the present study was to evaluate the physiological and sanitary quality of Cozumel hybrid melon seeds treated with the fungicide Thiabendazole. The experiments were conducted under a completely randomized design, consisting of 15 treatments in a 3×5 factorial system (three seed lots × five Thiabendazole doses: 0, 0.12, 0.2, 0.3 and 0.4% a.i.). The commercial product used was Tecto^® SC (485 g L^-1 of Thiabendazole). Four replications of 50 seeds were used for germination and vigor tests (evaluated by germination test first count: GFC). Eight replications of 50 seeds were performed for seed pathology analysis, amounting to 400 seeds per treatment. The average results were compared by Tukey test at 5% probability. The results showed differences in germination between lots, with lower total germination in lot 84538 (90.8%). There was no difference in Thiabendazole dosage regarding both total germination (94.8% on average) and GFC (93.2% on average), showing that the fungicide did not affect the physiological quality of seeds. Pathogenic species were not detected in the sanitary analysis, only saprophytic fungal species (Alternaria sp., Aspergillus spp., Curvularia spp and Penicillium spp.) and a general reduction in fungi incidence was observed with the increase of Thiabendazole doses.

Key words: Cucumis melo, seed treatment, fungicide.