Development and Evaluation of Hybrid Bermudagrass Varieties with Cold Hardiness for Golf Course Putting Greens

Abstract

Conversion from creeping bentgrass (Agrostis stolonifera L.) to hybrid bermudagrass [Cynodon dactylon (L.) Pers. x C. transvaalensis Burtt-Davy] on golf course putting greens in Oklahoma and other transition zone states is on the rise. In many instances, bermudagrass has proven well adapted and more economical on putting greens than creeping bentgrass in the transition zone and farther south in the USA. With increased use, a need and opportunity for development of new advanced hybrid bermudagrasses has developed. Improvement in shade and cold tolerance is desired. Work has been conducted to develop a number of bermudagrass lines with apparent improved winter hardiness at Oklahoma State University (OSU). This research was designed to test seven promising OSU experimental bermudagrasses (OKC) and three advanced experimental types from Mississippi State University (MSB) against five industry standards. In addition to screening for the best performing experimental bermudagrass lines for putting greens, the study was to provide more information regarding the performance of commercially available bermudagrasses in Oklahoma. Results showed `MSB-264', `MSB 281' and `MSB 285' have outstanding density, quality and color retention but demonstrated aggressive seed head expression. Amongst OSU experimental types, `OKC 70-18' had the highest mean visual quality at a value of 6 while `OKC 1-75-2' had the fastest establishment rate, high density and a dark green hue during summer months in addition to the lowest seed head expression. `OKC 13-78-5', which was in the group of varieties to first reach 100% coverage, exhibited rapid green up, second only to OKC 70-18 and had good performance in regard to color retention and visual color during the growing season. `OKC 7-20-22' and `OKC 18-4-Powell were two of the worst performers with respect to all parameters measured except for green speed. Amongst commercially available types, `Champion Dwarf' and' TifEagle' ranked the highest in color, quality and density while having minimum seedhead expression. However, TifEagle performed slightly better in early green up and late season color retention. The newly released commercially available cultivar `Sunday' bermudagrass was also in the group of good performance with the second lowest amount of winterkill, very fine texture, high density and quality. Commercial standards generally had superior performance over all experimental entries in every parameter measured other than establishment rate and late-season color retention. Based on the findings of this work, golf course superintendents are advised to carefully consider all cultivar performance attributes of newer lines before making a decision to switch from existing commercially available standards to any new or future releases.