Search Results
You are looking at 1 - 5 of 5 items for
- Author or Editor: Robert C. Shearman x
Attempts to establish buffalograss [Buchloë dactyloides (Nutt.) Engelm.] turfs from sprigs have been limited and successful stand establishment has been inconsistent. This study was conducted to determine whether accumulated growing degree-days (GDD) and cultivar of harvested sprigs have an effect on buffalograss sprig establishment. Two field studies were conducted on a Tomek silty-clay loam (fine smectitic mesic Pachic Agriudolls) in 2007 and again in 2008. The cultivars Legacy, a hexaploid, and Prestige, a tetraploid, were used in this investigation. Sprigs were harvested and planted on 29 June, 17 July, 31 July, and 15 Aug. in 2007 and 15 May, 4 June, 19 June, 2 July, 21 July, 31 July, and 18 Aug. in 2008. The GDDs were back-calculated from these harvest dates. The harvest date of the sprigs represented 1050, 1380, 1670, and 1980 GDD in 2007 and 120, 380, 620, 840, 1200, 1400, and 1720 in 2008. Aboveground buffalograss phytomass and percent buffalograss groundcover data were collected in 2007 and 2008. In 2008, total available sugar and starch content of harvested sprigs were determined for each sprig harvest date. In the 2007 studies, sprigs harvested at 1050 GDDs resulted in the best establishment for both cultivars. In the 2008 studies, ‘Legacy’ established successfully through 840 GDDs, and ‘Prestige’ established through 1200 GDDs. Sugar or starch content did not appear to influence sprigging success. These results support the recommendation to establish buffalograss from sprigs harvested before 1050 GDDs for best results.
Nutrient and chemical changes in turfgrass sand-based root zones are not well understood. This study was conducted to characterize nutrient and chemical properties in putting greens influenced by root zone mixture and establishment treatment, putting green age, and soil depth. Putting greens were constructed and established with Agrostis stolonifera L. in sequential years from 1997 to 2000. Treatments included root zone mixtures of 80:20 (v:v) sand and sphagnum peat and 80:15:5 (v:v:v) sand, sphagnum peat, and soil, and accelerated versus controlled establishment. In the establishment year, the accelerated treatment received 2.6-, 3.0-, and 2.6-fold more nitrogen, phosphorus, and potassium, respectively, than the controlled treatment. Soil samples were taken in Fall 2001, Spring 2004, and Summer 2004 and were analyzed for nutrient and chemical properties such as pH, cation exchange capacity (CEC), organic matter (OM), total soluble salts (TSS), and 12 nutrients. The root zone mixture and establishment treatments had minimal effects on most nutrient and chemical properties with the exception of phosphorus and pH. Cation exchange capacity, OM, TSS, and all nutrients decreased with soil depth, whereas soil pH increased. The putting green age × soil depth interaction was significant for many of the nutrient and chemical properties, but separating soil samples into mat and original root zone instead of predetermined soil sampling depths eliminated most of these interactions. The mat layer had higher CEC and OM values and nutrient concentrations and lower pH values than the original root zone mixture.
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.
There is a dearth of information about turfgrass drought resistance and adaptation in the Mediterranean region of Turkey. Turfgrass managers in this region need this information to help them make informed decisions regarding turfgrass selection and management. This research was conducted to assess the drought resistance of bermudagrass (Cynodon dactylon), buffalograss (Buchloe dactyloides), bahiagrass (Paspalum notatum), seashore paspalum (Paspalum vaginatum), zoysiagrass (Zoysia japonica), centipedegrass (Eremochloa ophiuroides), and tall fescue (Lolium arundinaceum) under Mediterranean conditions of Turkey. The study was conducted at two locations, Antalya and Mersin, and was repeated in 2006 and 2007 at both locations. One year after establishment, the turfs were subjected to drought stress for 90 days, which was followed by resumption of irrigation for recovery of the turf. Percentage leaf firing, turfgrass quality, and percent green shoot recovery were recorded. There were inter and intraspecies differences detected for percentage leaf firing and shoot recovery. Bermudagrass, bahiagrass, and buffalograss exhibited superior drought resistance as demonstrated by lower leaf firing and better shoot recovery values when compared with other species studied. Centipedegrass and zoysiagrass demonstrated a high leaf firing and very poor shoot recovery, whereas zoysiagrass and tall fescue were unable to recover from the drought stress in the sandy soil. Results showed that ‘SWI-1045’ (Contessa®) and ‘SWI-1044’ bermudagrass and ‘Cody’ buffalograss possessed superior drought resistance with acceptable turfgrass quality up to 30 days under drought stress that can be used for water-efficient turf management under the Mediterranean environment.
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.