Evaluation of Kentucky Bluegrass Cultivars and Selections Under Reduced Input Management.

Kentucky bluegrass (Poa pratensis L.) is a widely utilized cool-season turfgrass for golf courses, sports fields, and home lawns in the United States and Canada.  Managing Kentucky bluegrass with fewer inputs (i.e. irrigation, fertility, mowing) may negatively impact the performance and functionality of the species.  Consequently, research is needed to identify novel germplasm and develop improved cultivars that exhibit better quality when managed under reduced input regimes.  The main objective of this research was to evaluate cultivars and lines of Kentucky bluegrass managed with reduced irrigation, pesticide, and fertilizer applications in order to make cultivar recommendations for turfgrass managers and to develop new commercially available cultivars.  In September 2013, 317 cultivars and selections were seeded at the Rutgers Plant Biology and Pathology Research and Extension Farm in Freehold, NJ.  Spring green-up (1 – 9, 9 = earliest green-up), turf quality (1 – 9, 9 = best overall quality), drought resistance (1 -9, 9 = most resistant to drought) and disease tolerance (1- 9, 9 =  lowest amount of disease) were visually rated during 2015 and 2016.  Significant differences in turf quality, drought resistance, and disease tolerance were detected among the Kentucky bluegrass lines and cultivars evaluated.  The experimental line A04-13 exhibited significantly better turf quality (average value of 7.1) compared to 278 of the other entries evaluated in addition to having good disease and drought tolerance.  The cultivar Julius and experimental line GO-5675KBG had lower turf quality (average value of 1.2) compared to 314 of the other entries and generally had poor disease and drought tolerance as well.  Overall, this information will be used to identify cultivars that can be managed under reduced inputs and to select lines that will be developed into commercially available cultivars.