Cynodon, a small but important genus of the tribe Chlorideae, contains some of the world's most important grasses. These warm-season, sod-forming, perennial grasses are widely used in tropical and warmer temperate regions of the world for soil stabilization, turf and livestock herbage (Burton, 1977; Harland, 1970 and Juska and Hanson, 1964). The most widely distributed and best known taxon of the genus is C. dactylon, known variously in different parts of the world by the common names bermuda, couch, kweek, and doob (Beehag and Jacobs, 1992; Kneebone, 1966). By virtue of its wide geographic distribution and enormous variability, C. dactylon is economically the most important species of the genus (Taliaferro, 1995). Eight species of Cynodon are recognized, of which turf types are included only in the 2n = 36 C. dactylon (L.) Pers. var. dactylon (common bermudagrass), the 2n = 18 C. transvaalensis Burtt-Davy (African bermudagrass), and their 2n = 27 interspecific hybrid C. x magenissii Hurcombe (= C. dactylon x C. transvaalensis) (Harlan et. al., 1970a).
Bermudagrass (Cynodon spp.) was introduced to the USA from Africa by 1751 (Hanson, 1972a). Warm-season grasses such as Cynodon spp. differ from cool-season turfgrasses in having a four-carbon (C4) molecule, contrasting with three-carbon, as the first step in carbohydrate assimilation. Their C4 physiology is associated with low CO2 compensation concentration. This adaptation system provides high growth rate at high light intensity levels and high temperatures. The high growth rate of this genus provides it with rapid colonization in disturbed areas and quick recovery from traffic damage caused in sports activities. The fine-leaved texture of bermudagrass was recognized as an advantage for use in lawns, but its intolerance to shade was also noted (Enlow and Stokes, 1929). Arizona grown seed (probably common, C. dactylon), was planted in most golf course fairways, greens, and tees in Florida in the 1940's.
Bermudagrass is widely adapted in a number of climatic zones around the world. In North America bermudagrass is adapted to zone 8 and 9 (Transitional-Humid and Warm Humid Subtropical, respectively). It performs best with irrigation in zone 2, 11 and 12 (Dry-Summer Subtropical Mediterranean, Warm Semi-Arid Steppe and Warm Desert, respectively). Some cold tolerant varieties extend into the northern region of zone 8 (Transitional-Humid) and the southern region of zone 7 (Warm-Summer-Humid Continental). Cynodon spp. have many of the following benefits and limitations regarding cultural practices and turf management on the golf course, home lawn or sportsfield.
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Generally the turfgrass industry has recognized the use of two types of bermudagrass. The sterile interspecific hybrids 2n = 27 interspecific hybrid C. x magenissii Hurcombe (= C. dactylon x C. transvaalensis) which are propagated by vegetative cuttings, sprigs, plugs and sod. And the common synthetic or land race varieties 2n = 36 C. dactylon (L.) Pers. var. dactylon or common bermudagrass propagated by seed. There is confusion about many of the new and improved varieties being developed by public institutions and private industry. Attached is a short outline of common breeding protocol among the Cynodon spp. utilized in the turf and forage industry.
In 1989 Cebeco International Seeds, Inc. and Arizona Grain Inc. entered into a cooperative breeding program in C. dactylon for turf and forage grass improvement. The seeded bermudagrass industry based in the southwestern US is dominated by a single land race Arizona Common (16-18 million lbs. annually). The non-proprietary nature of the industry and a need in the marketplace for improved seeded bermudagrass varieties justified breeding activities in this species. In addition, of all the warm and cool season species improved seeded bermudagrass varieties will play a predominate role in low maintenance, low input turf and forage programs in the coming decade. Bermudagrass has a low ET rate, low height of cut tolerance, is tolerant to saline soil conditions, provides excellent traffic tolerance, is drought tolerant (dehydration avoidant and resistant, Beard, 1989), and good forage quality and quantity. In an era of resource management and environmental stewardship improved seeded bermudagrass varieties will have a favorable impact in the marketplace.
Cebeco International Seeds, Inc. Research and Development Goals and Objectives from 1989-2000 are as follows:
Seeded Bermudagrass Varieties From Cebeco International Seeds, Inc.
MIRAGE (turf type)
New and improved with excellent TQ, uniform turf growth, medium leaf texture and decumbent/vertical turf growth Synthetic derivative of northern and southern germplasm sources. Predominantly rhizomatous in growth habit. Improved erect growth for excellent playability on tees, fairways, near rough or sports fields. "Cold blooded" variety with improved cold tolerance, early spring green up northern bermudagrass adaptation. Durable sod strength. Top performer in 1992 NTEP bermudagrass test (1993 and 1994 Progress Report) Accepted as official variety by NGVRB in 1995 Commercial quantities available in 1995 and 1996.
PYRAMID (turf type)
New and improved with improved TQ, uniform turf growth, fine leaf texture and decumbent/aggressive horizontal turf growth. Self-compatible plant introduction from Afghanistan screened for utilization in the domestic and international turfgrass industry. Predominantly stoloniferous in growth habit with very dark green turf color. "Warm blooded" turf variety best adapted to warmed regions of the bermudagrass belt. Accepted as official variety by NGVRB in 1996 Small commercial quantities available in 1996 with large commercial supply in 1997.
EXPERIMENTAL 90160 (forage type)
New and improved forage type developed for domestic and international forage market. Exhibits improved cold tolerance and deep extensive rhizomatous growth habit. Synthetic derivative of northern and southern germplasm sources. Late maturity will enhance forage quality attributes in temperate regions of the forage bermudagrass market. Small quantities available for testing in 1997 with commercial release in 1998.
Seeded Varieties
HYBRID BERMUDAGRASS has:
Vegetatively Propagated Varieties
TRIPLOID BERMUDAGRASS has:
Seeded Varieties
SELF COMPATIBLE BERMUDAGRASS has:
Seeded Varieties
SYNTHETIC BERMUDAGRASS has:
and/or
