Abstract

The constant assessment of methods of disease control is essential in achieving production regularity and for ongoing increments in soybean productivity. Among the various diseases, the intensity of the white mold has been increasing, caused especially by the fungus Sclerotinia sclerotiorum (Lib.) de Bary. The present work has the objective to assess different seed treatments in association with fungicide application to control the white mold in soybean. The experimental design used was complete randomized blocks design with split plots. In the plots, the treatments were: control - no seed treatment; Certeza® (thiophanate methyl + fluazinam 45 + 60 g ha-1) and Trichodermil® (Trichodermaharzianum ‘1306’ 1.250 mL 100 kg-1 - 109 viable spores mL-1). In each seed treatment, the application was done on aerial part of subplots.The treatmentsin aerial part were: control (with no fungicides application); three applications of Derosal® (carbendazim) 1.000 gi.a./ha-1 in R1, R2 and R5.1; three applications of Cercobin 700 WP® (thiophanate methyl) 600 gi.a./ha-1 in R1, R2 and R5.1;Cercobin 700 WP® (thiophanate methyl) in R1, Sumilex (procimidone) 750 gi.a./ha-1 in R2 and Frowncide (fluazinam) 750 gi.a./ha-1 in R5.1.There were assessments on the emergence and height of the plants in V3 and the severity of the disease at the phenological stages R1, R3, R5.5 and R7. The variables thousand-grain weight, productivity and the economic analysis were determined after the harvesting of the plots. The treatments of seeds with thiophanate methyl+ fluazinam and Trichoderma harzianum and the applications of thiophanate methyl, procimidone and fluazinam on the aerial part stood out in the control of the disease. The net income showed that despite the high cost of the plant protection products, there were increases in the profitability of the crop.

Key words: White mold, Glycine max, Economic analysis.