Evaluación de la eficiencia de fungicidas para el control de las enfermedades de fin de ciclo y la roya asiática de la soja en Tucumán, Argentina

PLOPER, L. D.; GONZALEZ, V.; HECKER, L., ; REZNIKOV, S; DEVANI, M.

Análisis de Semillas

Estudio Rolando

Lugar: Rosario. Argentina; Año: 2011 vol. 3 p. 98 - 107

1851-1678

Diseases may severely restrain soybean [Glycine max (L.) Merr.] production, especially when crops are grown under management systems and environmental conditions that favor various pathogens. This paper reports the results of field trials, which were conducted throughout three growing seasons to evaluate the efficiency of different active ingredients and application timing in controlling soybean late-season diseases (LSD) and Asian rust. The trials were carried out on A 8000 RG, soybean cultivar from maturity group VII, in Puesto del Medio, Burruyacú, Tucumán, during the 2007/2008, 2008/2009, and 2009/2010 growing seasons. Evaluated active ingredients were one triazol (flutriafol), four strobilurin plus triazol mixes (pyraclostrobin + epoxiconazol, trifloxystrobin + cyproconazol, azoxystrobin + cyproconazol, and metominostrobin + tebuconazol), and one benzimidazol plus triazol mix (carbendazim + tebuconazole). Treatments were applied at R3, R5 or R3+R5. Parameters assessed were: disease severity, foliar persistence (at early R7), yield (kg/ha), 1000-seed weight (g) and seed infection (%). In the 2007/2008 season, all treatments were superior to the untreated control for disease control, yield, and 1000-seed weight. In the 2008/2009 season, no statistically significant differences were found among treatments for yield and 1000-seed weight, whereas in the 2009/2010 season the only treatment that differed from the control for yield was the azoxystrobin + cyproconazol mix at R5, while the trifloxystrobin + cyproconazol (at R3) and azoxystrobin + cyproconazol treatments (both at R3 and R5) differed from the control for 1000-seed weight. The treatments which gave the best results for the evaluated parameters and had a stable behavior throughout the three seasons were the following: pyraclostrobin + epoxiconazol, trifloxystrobin + cyproconazol and azoxystrobin + cyproconazol on both application moments (R3 and R5). By contrast, carbendazim + tebuconazol, metominostrobin + tebuconazol, and flutriafol treatments had a variable behavior throughout the evaluated seasons. Concerning seed quality, fungicide applications generally decreased fungal infection and improved root emergence. These results confirm that although LSD and rust severity levels were moderate, crop protection resulted in yield increase and improved seed quality. In addition, results showed that there are efficient active ingredients for the management of these diseases.