A study was conducted last summer at Ohio State to look at summer seeded perennial ryegrass, since many athletic field managers have only a short period of time in the summer to get ground cover established between the spring & fall playing seasons. One of the aims of the study was to see if an application of a preventative fungicide would have much effect on disease incidence, particularly since the grass was perennial ryegrass which is very susceptible to seedling diseases like pythium in the summer.
The seed was applied 7/17/08 and germinated 4 days later. Almost immediately it became apparent that the plots that received the fungicide (in this case granular Subdue Maxx) at the time of seeding were establishing much quicker than the plots that did not.
There were no visible signs of pythium foliar blight on any of the research plots (treated or untreated) but there were marked differences in turf quality between those plots that were treated and those that were not (Picture, left).
* Increased biomass/verdure – 7 grams of dry tissue collected from fungicide-treated plots versus 0.15 g from the untreated turf.
* Better turf quality – color, density, uniformity
* Greater percentage of tissue nitrogen – 3.76% N from fungicide-treated plots, compared to 3.16% N from the untreated turf
* Play-ready turf by 4 weeks, instead of the typical 6 weeks needed between seed and play with perennial ryegrass
This study was repeated in October with no results, suggesting that the fungicide is either suppressing soil pathogens that are active in warm soil and inhibit turf establishment, or the fungicide is somehow enhancing turf growth.
The study will be repeated in 2009 with our turfgrass pathologist, Joe Rimelspach, and will include identification of any soil pathogens involved.
Posted by Pamela Sherratt & John Street. www.buckeyeturf.osu.edu