Reduced‐growth, glyphosate‐resistant Kentucky bluegrass (Poa pratensis L.) has recently been developed. There has been no comparative analysis of the newly developed transgenic Kentucky bluegrass lines to conventional cultivars or tissue culture‐derived lines to determine vegetative and flower characteristic differences and similarities. This study measured the vegetative and reproductive characteristics of the transgenic lines, tissue culture‐derived control lines, and reference cultivars during 2004 and 2005, in Ames, IA. The study was conducted in a noncompetitive, nonmown, spaced plant setting. Data collection of vegetative characteristics included rhizome spread and total plant area. Data collection for flower characteristics included flower phenology and morphological characteristic measurements, including panicle length, number of spikelets per panicle, and flag leaf characteristics. Transgenic lines as a group exhibited 29 and 32% less rhizome spread than the reference cultivars and tissue culture‐derived control lines, respectively, in 2004 and 37 and 40% less rhizome spread than reference cultivars and tissue culture‐derived control lines, respectively, in 2005. Flower emergence times for all transgenic lines were comparable to their respective tissue culture‐derived control lines and reference cultivars.

No abstract

Core Ideas Genetic differences in dollar spot susceptibility among bentgrasses are consistent across the Central U.S.A. at putting green and fairway mowing heights and with or without fungicides. ‘Kingpin’ or ‘Memorial’ creeping bentgrass had the least dollar spot injury and ‘Crystal BlueLinks’, ‘Declaration’, ‘L‐93’, and ‘SR1150’ were consistently in the same statistical grouping as these cultivars. Golf course superintendents should use National Turfgrass Evaluation Program or similar data from as near their location as possible to assess seasonal cultivar performance, but relative dollar spot susceptibility should be applicable across broader regions if nearby data are not available.

No abstract