Development of Rhizoctonia solani on Stems, Stolons and Tubers of Potato II. Efficacy of Chemical Applications
2011
Atkinson, Dennis | Thornton, Michael K. | Miller, Jeffery S.
Fungicide treatments have proven successful in reducing Rhizoctonia solani lesions on stems and stolons; as well as black scurf on tubers. Field studies in Parma and Aberdeen, Idaho, were conducted in 2004 and 2005 to compare the relative effectiveness of in-furrow and seed treatments for disease control on stems, stolons and tubers. The effectiveness of each fungicide placement was evaluated for control of seed-borne and soil-borne inoculum. The systemic fungicide azoxystrobin was used as the in-furrow fungicide treatment and fludioxonil was used as the seed treatment. A combination of seed treatment with an in-furrow treatment was also evaluated. All fungicide treatments had significantly lower stem and stolon disease ratings than did the non-treated control. The seed plus in-furrow treatment tended to reduce stem and stolon disease ratings more than in-furrow treatment alone. Black scurf ratings on daughter tubers were significantly reduced by fungicide applications compared to the non-treated control in two of three trials. The combination treatment had lower black scurf ratings than the in-furrow treatment alone. There were more significant differences among fungicide treatments in Rhizoctonia solani lesions on stems, stolons and tubers when seed inoculum was moderate to high compared to low seed inoculum. In-furrow treatment was relatively more effective in reducing disease on stems, stolons and tubers when soil was the primary source of inoculum, while seed treatment was relatively more effective when seed was the primary inoculum source.
显示更多 [+] 显示较少 [-]