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  • Author or Editor: Desalegn Serba x
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Bermudagrass (Cynodon spp.) is a drought-resistant warm-season turfgrass adapted to the southern and transitional zones in the United States. Multiple hybrid cultivars have been developed and released for use as turfgrass, and others are still undergoing development. Increasing genetic diversity of commercial cultivars is vital to stress tolerance. A DNA profiling study of 21 experimental selections from the Oklahoma State University turfgrass breeding program and 11 cultivars was conducted using 51 simple sequence repeat primer pairs across the bermudagrass genome. A pairwise genetic relationship analysis of the genotypes using 352 polymorphic bands showed genetic similarity coefficients ranging from 0.59 to 0.89. The average pairwise population differentiation values were 0.012 for the 11 cultivars and 0.169 for the 21 selections. A cluster analysis using the unweighted paired group with the arithmetic average method grouped the entries into six clusters. A correlation analysis identified different levels of pairwise genetic relationships among the entries that largely reflected parental relationship. Directional breeding and selection for cold hardiness or drought resistance created progeny that had distinct genetic diversity in the tested bermudagrasses. It is evident that an increase in genetic diversity of the existing cultivar pool with the release of one or more experimental selections for commercial use will strengthen and improve bermudagrass systems.

Open Access

Low-quality (i.e., impaired) water sources are commonly used to irrigate warm-season turfgrass landscapes as a result of limited supplies of potable water sources. Currently, there is great need to define the impacts of impaired water sources on turfgrass water consumption, growth, and quality. The objectives of this study were to characterize actual evaporation (ETa), clipping production, and quality of three hybrid bermudagrass varieties [‘TifTuf’, ‘Tifway’, and ‘Midiron’; Cynodon dactylon (L.) Pers. × C. traansvalensis Burtt Davy] grown under three water sources [reverse osmosis (RO), local well, and recycled], each supplied at full irrigation levels (1.0 × ETa) over two 8-week study periods. When pooling across water source and date, TifTuf maintained the highest visual quality and normalized difference vegetation index (NDVI) compared with both Midiron and Tifway. This was accompanied by a greater daily ETa rate, clipping production, and water use efficiency (WUE) compared with Midiron in both studies. When pooling across variety and date, daily ETa of turfgrass receiving recycled water was 5% to 10% less than those receiving the local well or RO water. In addition, turfgrasses receiving local well water held the greatest visual quality and NDVI compared with those receiving either RO water in the summer study. Visual quality and NDVI were also less in turfgrasses receiving RO water compared with those receiving local well or recycled water in the fall. Despite turfgrasses having a lower ETa under recycled water in both study periods, these plants had significantly greater clipping production compared with RO water in the summer. Also, clipping production under recycled water did not differ significantly from the other two sources in the fall study. Furthermoe, in both studies, WUE was similar for turfgrasses receiving recycled water compared with those receiving RO or local well water. Results demonstrated that irrigation water quality influences critical factors for hybrid bermudagrass growth and that considerable variability exists among three commercially available varieties for evapotranspiration rates, quality, and clipping production.

Open Access

Buffalograss [Buchloe dactyloides (Nutt.) Engelm.] use as a fairway turfgrass is limited in northern portions of its adaptation zone by its extended winter dormancy and tan coloration in early spring and late fall. Cool-season grasses mixed with buffalograss could enhance turfgrass appearance and performance in fall and early spring. Research was conducted near Mead, NE, with eight buffalograss genotypes maintained under fairway conditions to determine the effect of blue fescue (Festuca ovina L. var. glauca Lam.) overseeding rate on turfgrass performance. Interactions were nonsignificant in most cases so main effects are emphasized. Differences were observed between seeding rates and genotypes for most traits studied. Overseeding blue fescue enhanced spring green-up, fall color retention, stand density, and turfgrass quality. These effects were most pronounced in late fall and early spring, when buffalograss plants were entering or exiting winter dormancy. The 5 g·m−2 blue fescue overseeding rate improved all performance traits studied when compared with the nonoverseeded buffalograss control and was not different from the 10 g·m−2 seeding rate treatment. Thus, the 5 g·m−2 blue fescue overseeding rate appeared to be near optimum for overall turfgrass performance, offering reduced seed cost and decreased potential for species interference. The ‘Legacy’ buffalograss and ‘SR-3200’ blue fescue mixture had the best performance of the genotypes studied as a result of their visual compatibility in terms of color similarity.

Free access

Hybridization and selection has been one of the methods used to generate turfgrass cultivars in buffalograss improvement. Three half-sib populations were developed by crossing three buffalograss female genotypes, NE 3296, NE 2768, and NE 2769, with NE 2871, a male genotype, to 1) investigate the pattern of genetic variability generated for turfgrass characteristics through hybridization; 2) assess the effect of parental change on the level of genetic variability generated in a buffalograss diploid population; and 3) predict the performance of a progeny generated from two heterozygous parents for turfgrass performance. The four parents and 20 random F1 progeny selected from each population were established in 2006 at the John Seaton Anderson Turfgrass Research Facility located near Mead, NE. A randomized complete block design (RCBD) was used with the progeny nested in the crosses. A visual rating scale of 1–9 was used to evaluate the population. Mean population lateral spread, genetic color, density, and turfgrass quality from early summer to fall ranged from 3.5 to 4.5, 7.1 to 7.9, 6.9 to 8.1, and 5.2 and 6.8, respectively. There were significant differences among the crosses and the parents for all the traits studied except quality in June and August. The progeny nested within crosses differed for turfgrass genetic color and quality. Best linear unbiased prediction (BLUP) indicated a high improvement potential for turfgrass lateral spread and spring density in NE 2768 × NE 2871 and for turfgrass genetic color in NE 3296 × NE 2871. From these findings, it can be concluded that hybridization breeding is a worthwhile approach for generating and identifying transgressive segregants for specific buffalograss traits.

Free access