Turf performance of seeded bermudagrass cultivars - GCSAA

Turf performance of seededbermudagrass cultivarsThey’re getting better, but they’re still not as good as Tifway.H. Wayne Philley and Jeffrey V. Krans, Ph.D.R E S E A R C HKEY POINTS■ New seeded bermudagrass cultivarsoffer improvements inturf density, leaf texture andturf quality.■ Winter survival during theestablishment year can be difficultto achieve.■ The top turf performers havenot yet produced enough seedto meet demand.The number of seeded turfbermudagrass cultivars hasincreased enormously in thepast decade. In 1995, we initiateda variety test because wewere fielding so many questionsand comments aboutthese cultivars.This test included 16 seededcultivars grown under simulatedfairway conditions withmowing scheduled three timesper week at 3 ⁄4-inch height witha reel mower.Also under way at our site isthe 1997 national bermudagrass test,which includes 20 seeded and 10 vegetativecultivars. From these two trials andfrom previous tests we conducted cooperativelywith other agencies, we’vedeveloped significant insights intoseeded bermudagrasses.Tifway for comparisonTifway, a hybrid of Cynodon dactylonand C. transvaalensis, is the most widelyused bermudagrass cultivar on fairwaysand tees. It’s a sterile vegetative cultivarthat produces high-density, fine-textured,wear-resistant turf. The goal ofbreeders is to achieve the performanceof Tifway with a seeded bermudagrasscultivar. Our evaluations of seeded cultivarshave included plots of vegetativelyplanted Tifway for comparison.In each experiment, we used the formatfor rating adapted by the NationalTurfgrass Evaluation Program, includingthe randomized complete block designwith three replications of each cultivar.Photos courtesy of Wayne PhilleyImproved seeded cultivars can provide high turf density and fine leaf texture.Seedling vigorSeedling vigor ratings include germinationand seedling growth. In threeyears of seeding (1995-1997) we evaluatedthis feature two to three weeks afterseeding and prior to the first mowing.With their rapid upright growth,Arizona Common, NuMex Sahara andBlue-muda displayed high seedlingvigor in each planting. After mowingwas initiated, these cultivars wereGolf Course Management ■ November 1998 1

anked near the bottom in turf performanceratings. Low-growing cultivars,including Princess, Sundance, Savannah(4), and PST-R69C, displayed lowerseedling vigor but higher performanceafter initiation of mowing. Seededbermudagrass has been well known foreasy establishment because of rapid germinationand growth. Compared withother warm-season species, none of thecultivars evaluated had unacceptableseedling vigor.Turf qualityTurf quality ratings are the mostused tool for evaluating turfgrasses. Inour evaluation of bermudagrasses weconsidered several components to arriveat quality scores — uniformity, density,leaf texture, color and the presence orabsence of seedheads. Quality ratingswere made twice monthly during eachgrowing season.The seeded cultivars that maintainedthe highest quality scores includedPrincess, Sundance and Savannah. Mostcultivars achieved quality that wassignificantly higher than ArizonaCommon, including NuMex Sahara.Princess, Sundance, Savannah,Sultan, Sunstar, Del Sol, ED1, Mirage,Sundevil II, MD2, Sonesta, PST-R69C,SW1-11, J-1224, J-540 and OKS 95-1 alldisplayed significantly higher turf qualitythan NuMex Sahara for at least onegrowing season in one or more experiments.None of the seeded cultivarsachieved the turf quality of Tifway.Leaf textureLeaf texture (blade width) and turfdensity have improved more than anyother aspect of turf quality as a result ofbreeders’ work with seeded bermudagrass.These traits are usually linked —the finer the leaf blades, the higher theturf density. In our evaluations,Princess, Sundance and Savannah displayedthe finest leaf texture amongseeded cultivars. Sultan, Sundevil II, DelSol, Sunstar and Mirage were also significantlyfiner than NuMex Sahara andArizona Common. Tifway was significantlyfiner than any seeded cultivar.Guymon bermudagrass had the coarsestleaf texture in our experiments, followedby ED5.Turf densitySeeded cultivars receiving the highestdensity ratings (number of shoots perunit area) were Princess, Sundance andSavannah. Other cultivars with significantlyhigher density than NuMexSahara included Sultan, Sunstar,Sundevil II, Mirage and ED1. Density ofTifway was significantly greater thanany seeded cultivars.ColorWe did not observe great differencesin genetic color among seededbermudagrass cultivars. Most differencesamong plots on any date of ratingscould be attributed to injury ordefoliation. Cultivars that grow moreupright, such as Arizona Common, havea greater tendency to scalp, which affectscolor. When comparing healthy leaves,differences among seeded cultivarsappear to be subtler. The color of Tifwayis different from seeded cultivars.continuedAvailability of the top cultivarsSources for the top three seeded bermudagrass cultivarsin our trials — Princess, Sundance and Savannah —acknowledge that breeding for turf quality often reducesseed yield.Seeds West Inc. reports the initial seed production ofPrincess was low. Only very limited seed was available in1998. Better availability is expected in 1999. Sultan,another noteworthy cultivar from the same company, ispresently available in good supply.Lesco informed us that seed yield of Sundance hadbeen unacceptable. Out of Sundance, Sundance II hasbeen selected for improved seed yield. We look forward toevaluating Sundance II’s turf quality beginning in 1999.Sunstar is commercially available from the same companyin good supply.Pure Seed Testing Inc. reports that the early yield ofSavannah has been encouraging. Supply is limited at presentbut should be good by 2000.R E S E A R C HGolf Course Management ■ November 1998 2

Cultivars evaluatedcontinued from p. 63Rhizome densityBermudagrasses have stolons(aboveground stems) and rhizomes(belowground). Rhizomes can aidin recovery when the turf surfaceis removed or injured. Rhizomescontribute to winter survival andsod strength.To evaluate the quantity of rhizomesin each cultivar, we dried out plugsfrom each plot and weighed rhizomestem material. Dry weights weredivided by the volume of the sample toarrive at the rhizome density. Ourresults showed that rhizome densityenhanced winter survival but didn’talways correlate with shoot density.Guymon, for example, received thelowest turf-density rating, but rankedR E S E A R C HThe following are the seeded turf bermudagrass cultivars evaluated at Mississippi State Universityfrom 1995 to 1998.ExperimentalCultivar designation Source Years evaluatedED1 Cascade International Seed Co. 1995,1996, 1997, 1998MD2 Cascade International Seed Co. 1995,1996, 1997, 1998ED5 Cascade International Seed Co. 1996,1997, 1998MD8 Cascade International Seed Co. 1997, 1998Blue-muda DSM-200 Desert Sun Marketing 1995,1996, 1997, 1998Pyramid CD 90183 International Seeds Inc. 1995,1996, 1997, 1998Mirage CD 90173 International Seeds Inc. 1996,1997, 1998Sundance B14 Lesco 1995,1996, 1997, 1998Sunstar B618 Lesco 1995,1996, 1997, 1998Del Sol B26-14 Turf Merchants Inc. 1995,1996, 1997, 1998Sundevil II Medalist of America 1995,1997, 1998Sultan FMC-6 Seeds West Inc. 1995,1996, 1997, 1998Princess FMC-77 Seeds West Inc. 1995,1996, 1997, 1998SW 1-7 Seeds West Inc. 1997, 1998SW 1-11 Seeds West Inc. 1997, 1998NuMex Sahara NMS-1 Seeds West Inc. 1995,1996, 1997, 1998Arizona Common Seeds West Inc. 1995,1996, 1997, 1998Sonesta NMS-3 O.M. Scott & Sons Co. 1995Savannah PST-R64 Pure Seed Testing Inc. 1996,1997, 1998Panama PST-R63 Pure Seed Testing Inc. 1997, 1998PST-R69C Pure Seed Testing Inc. 1997, 1998J-540 Olsen-Fennel Seed Co. 1997, 1998Blackjack Olsen-Fennel Seed Co. 1997, 1998J-1224 Jacklin Seed Co. 1997, 1998Jackpot J-912 Jacklin Seed Co. 1997, 1998Shangri La Zajac Performance Seed 1997, 1998Majestic H&H Seed Co. 1997, 1998OKS 95-1 Oklahoma State Univ. 1997, 1998Guymon GX59 Johnston Seed Co. 1995,1996, 1997, 1998Golf Course Management ■ November 1998 3

consistently highest among seeded cultivarsin rhizome density. Princess, oneof the denser cultivars, had few rhizomeson some dates of measurement.Other cultivars with high rhizomedensity were Sundance and ED1. Mostcultivars were not significantly differentfrom Arizona Common. Tifwayproduced more rhizomes than anyseeded cultivar.Spring green-upSpring green-up of bermudagrassshould not be confused with winter survival.We applied the spring green-uprating in years when temperatures hadbeen mild and there was no significantwinterkill.Spring green-up indicates the rate atwhich the cultivars break winter dormancyand begin spring growth. In thetest that we seeded in 1996, all plots survivedthe two winters that followed, butcultivars responded differently to thetwo different winters. In 1997, Guymondisplayed the earliest green-up, whileTifway and Arizona Common rankedamong the latest. In 1998, Tifway wasearly, while Guymon ranked among thelatest, with Arizona Common.Savannah displayedimproved springgreen-up over NuMexSahara and ArizonaCommon in bothyears of rating. Severalyears of evaluation areneeded to properlyrank the spring greenupof these cultivars.The minimum air temperature was near0 F.Local golf courses and some sodfarms experienced extensive winterkillof Tifway. Many fairways requiredreplanting, and Tifway sod was in shortsupply. Should fairways be plantedwith seed?Our Tifway plots established fromvegetative plugs in July displayed 55 percentwinter survival. Among the seededcultivars, Guymon averaged 17 percentsurvival while other cultivars displayed0 to 3 percent. Most of the same cultivarswere reseeded in June 1996 withonly minimal winter injury observedthe following spring.Our plots for the 1997 nationalbermudagrass test were planted July 10,1997. All plots — vegetative and seeded— were well established and under routinemowing before frost and winterdormancy. The 1997-1998 winter wasmild with the minimum air temperatureapproximately 20 F. Even so, theseeded cultivars suffered severe winterinjury. Vegetative cultivars (includingTifway) in the same test and seeded cul-continuedR E S E A R C HWinter survivalWe believe thepotential for winterkillduring theestablishment year is acritical factor indeciding whether toestablish bermudagrassfrom seed. Thefirst of these tests wasseeded on June 22,1995. The followingwinter in Mississippiwas considered severe.After the severe winter of 1995-96, Tifway bermudagrass displayed better survival than any seeded cultivar.Golf Course Management ■ November 1998 4

continued from p. 65tivars in the adjacent 1996 plantingshowed almost no injury.Among the seeded cultivars in the1997 test, Princess and the experimentalcultivars PST-R69C, SW 1-11 andOKS 95-1 had the best winter survival(greater than 80 percent survival comparedwith Arizona Common at 18 percent).Because this was a mild winter itshould not be concluded that theseeded cultivars with higher winter survivalin the establishment year are morecold tolerant.For our region we recommend seedingbermudagrass in spring and earlysummer if it will be maintained at lowmowing heights because close mowingincreases winterkill of bermudagrass. Iflate seeding is necessary, then raising themowing height late in the growing seasonmay increase chances of success.AvailabilitySeed production is often traded awayas breeders strive to improve the turfqualities of cultivars. That means it’soften hardest to obtain seed for thebest grasses.We contacted the sources of the topthree seeded bermudagrasses —Princess, Sundance and Savannah —and found that the initial seed productionof Princess (Seeds West Inc.) waslow, and the seed was not widely availablein 1998. Better availability isexpected in 1999. Seed yield ofSundance (Lesco) has been unacceptable.Sundance II has been selected forimproved seed yield. We look forward toevaluating Sundance II’s turf qualitybeginning in 1999. Supply of Savannah(Pure Seed Testing) is also limited atpresent but should be good by 2000.SummaryNew seeded bermudagrass cultivarsoffer improvements in turf density, leaftexture and turf quality. Lower and moreprostrate growth habit enables these newcultivars to perform at lower mowingheights than Arizona Common.Late seeding combined with lowmowing height may result in poor wintersurvival during the establishment year.Although the top turf performershave not yet produced enough seed tomeet demand, the future looks brightfor seeded bermudagrass. And althoughseeded cultivars have not met the performanceof Tifway, this goal is muchnearer than it was just a decade ago. ■References1. Alderson, J., and W.C. Sharp. 1994. Grass varietiesin the United States. USDA Agric.Handbook No. 170. U.S. Government PrintingOffice, Washington, DC.2. Baltensperger, A.A. 1989. Registration of‘NuMex Sahara’ bermudagrass. Crop Science29:1326.3. Baltensperger, A.A., and V. Meier. 1993.Registration of ‘Sonesta’ bermudagrass. CropScience 33:876.4. Fraser, M.L., and C.A. Rose-Fricker. 1998.Registration of ‘Savannah’ bermudagrass. CropScience 38:279.5. Samudio, S.H., and A.D. Brede. 1997.Registration of ‘Jackpot’ bermudagrass. CropScience 37:1380.6. Samudio, S.H., and A.D. Brede. 1998.Registration of ‘Cheyenne’ bermudagrass.Crop Science 38:279.7. Samudio, S.H., and A.D. Brede. 1998.Registration of ‘Sundevil’ bermudagrass. CropScience 38:537-538.8. Taliaferro, C.M., R.M. Ahring and W.L.Richardson. 1983. Registration of ‘Guymon’bermudagrass. Crop Science 23:1219.R E S E A R C HEven after a mild winter in Mississippi in 1997-98, bermudagrass cultivars seeded in July 1997(front) displayed severe winter injury compared with second-year plots (back) seeded inJune 1996.H. Wayne Philley is senior research assistant inMississippi State University’s department of plantand soil sciences. Jeffrey V. Krans, Ph.D., is professorof agronomy in the department.Golf Course Management ■ November 1998 5