Evaluation of fungicide and plant growth regulator tank-mix programmes on dollar spot severity of creeping bentgrass.

摘要

Dollar spot (Sclerotinia homoeocarpa F.T. Bennett) is a common and destructive disease of creeping bentgrass (Agrostis stolonifera L.). In 2003 and 2004, field studies were conducted to evaluate 14- and 21-day sequential fungicide tank-mix programmes alone and in combinations with plant growth regulators (PGRs) paclobutrazol, trinexapac-ethyl, or paclobutrazol plus trinexapac-ethyl on dollar spot of fairway-height creeping bentgrass. All fungicide-treated plots, either fungicides plus PGRs or fungicides alone, exhibited greater dollar spot control versus untreated plots. Overall, fungicide efficacy on dollar spot was comparable on plots treated with fungicide tank-mix programmes alone versus fungicides plus PGRs. Creeping bentgrass quality was consistently better in plots treated with fungicides plus PGRs versus fungicides alone. Dollar spot control and creeping bentgrass quality was improved, however, in plots treated with fungicides plus paclobutrazol versus fungicides alone, fungicides plus trinexapac-ethyl, or fungicides plus paclobutrazol plus trinexapac-ethyl..