Buffalograss [ Buchloe dactyloides (Nutt.) Englem.] is the only native grass that is being used extensively as a turfgrass in the Great Plains region. Its low-growth habit, drought resistance, and low-maintenance requirement make it attractive as a turfgrass species. Our objective was to obtain an overview on the genetic relatedness among and within seeded and vegetative biotype buffalograsses using inter-simple sequence repeats (ISSRs), random amplified polymorphic DNA (RAPDs), sequence-related amplified polymorphisms (SRAPs), and simple sequence repeats (SSRs) markers that were derived from related species (maize, pearl millet, sorghum, and sugarcane). Twenty individuals per cultivar were genotyped using 30 markers from each marker system. All buffalograss cultivars were uniquely fingerprinted by all four marker systems. Mean genetic similarities were estimated at 0.52, 0.51, 0.62, and 0.57 using SSRs, ISSRs, SRAPs, and RAPDs, respectively. Two main clusters separating the seeded-biotype from the vegetative-biotype cultivars were produced using UPGMA analysis. Further subgroupings were unequivocal. The Mantel test resulted in a very good fit (SRAP=0.92, ISSR=0.90) to good fit (RAPD=0.86, SSR=0.88) of cophenetic values. Comparing the four marker systems to each other, RAPD and SRAP similarity indices were highly correlated ( r=0.73), while Spearman's rank correlation coefficient between RAPDs and SSRs was r=0.24 and between ISSRs and SSRs was r=0.66. A genotype-assignment analytical approach might be useful for cultivar identification and property rights protection. Polymorphic SRAPs were abundant and demonstrated genetic diversity among closely related cultivars.

Peroxidases play an important role in plant stress related interactions. This research assessed the role of peroxidases in the defense response of resistant and susceptible buffalograsses [Buchloe dactyloides (Nutt.) Engelm] and zoysiagrasses (Zoysia japonica Steudel) to the western chinch bug, Blissus occiduus Barber. The objectives were: (1) to assess the relationships among protein content, basal peroxidase levels, chinch bug injury, and ploidy levels of chinch bug-resistant and -susceptible buffalograsses;(2) to compare peroxidase activity levels of resistant and susceptible buffalograsses and zoysiagrasses in response to chinch bug feeding; (3) and to analyze extracted proteins from chinch bug-resistant and -susceptible buffalograsses and zoysiagrasses by native gel electrophoresis to obtain information on the peroxidase profiles. Correlation analyses of 28 buffalograss genotypes with varying levels of chinch bug resistance and ploidy levels indicated that buffalograss total protein content was correlated (r = 0.47, P = 0.01) to chinch bug injury, while basal peroxidase levels was not (r = 0.19, P = 0.29), suggesting that the up-regulation of peroxidases in resistant buffalograsses is a direct response to chinch bug feeding. Three of the four chinch bug-resistant buffalograss genotypes evaluated had higher peroxidase activity in the infested plants compared to control plants. Peroxidase activity levels were similar between infested and control plants of the two highly susceptible buffalograss genotypes. Zoysiagrasses had lower peroxidase activity in general when compared to buffalograss control plants, and only 'Zorro' consistently showed higher peroxidase activity in the infested plants. Native gel electrophoresis analysis identified differences in the isozyme profiles of infested and control buffalograsses 'Prestige' and 196, and the zoysiagrass 'Zorro'. Results from this study suggest that peroxidases have the potential to be used as markers for selecting chinch bug resistant turfgrasses, and may help explain how plants defend themselves against biotic stresses, such as chinch bugs.

The relative wear tolerance of seven cool‐season turfgrass species was determined for both sled (foot‐like) and wheel (vehicular) wear injury. Four methods of evaluating wear tolerance differentials were used: 1) visual rating of wear injury, 2) percent total cell wall content (TCW), 3) percent verdure, and 4) percent chlorophyll/unit area remaining after wear treatment. Manhattan perennial ryegrass (Lolium perenne L.) was most tolerant to wheel wear; Kentucky 31 tall fescue (Festuca arundinacea Schreb.) and Merion Kentucky bluegrass (Poa pratensis L.) ranked second; Pennlawn red fescue (F. rubra L.) and Italian ryegrass (L. multiflorum Lam.) were intermediate; while Cascade chewings fescue (F. rubra var. commutata Gaud.) and rough bluegrass (P. trivialis L.) ranked lowest. The relative ranking for sled wear was slightly different from that for the wheel. Visual ratings indicated that Manhattan, Kentucky 31, and Merion were equally tolerant to sled wear. However, Merion was the most wear tolerant to sled injury, according to ratings based on the percent verdure remaining after treatment. Manhattan and Kentucky 31 ranked second and third, respectively; while, Cascade chewings fescue and rough bluegrass were almost destroyed by the crushing, tearing action of the sled. Wear tolerance differentiation among species for the four methods tested was in high agreement. However, percent verdure remaining was the preferred method for quantitatively evaluating wear tolerance differentials. It eliminated arbitrary decisions that were inherent in the visual rating system, and involved fewer procedural steps than either the percent TCW or percent chlorophyll content determinations.

Lowering mowing heights to increase creeping bentgrass (Agrostis palustris Huds.) putting green speed (i.e., ball roll distance) is a common practice. This practice can increase turfgrass susceptibility to heat and drought stress. Other cultural practices might be used to improve putting green quality and speed without additional stress. In this study, vertical mowing was used as a grooming technique to potentially improve putting green quality and speed. A ‘Penncross’ creeping bentgrass turf, established in 1986, was mowed daily at 3.2, 4.0, and 4.8 mm in combination with vertical mowing frequency treatments of 1 and 2 times per month, and a check of no vertical mowing. Mowing height and vertical mowing frequency effects on ball roll distance, turfgrass color and quality, and root production were evaluated in this study during 1989 and 1990. Vertical mowing treatments did not affect ball roll distance, turfgrass color and quality, or root production. Ball roll distance decreased by 0.2 m in 1989 and 0.4 m in 1990 as mowing height increased from 3.2 to 4.8 mm. Relative putting green speeds were rated as fast (i.e., > 2.6 m) across mowing height in 1989, and medium‐fast to fast (i.e. 2.3–2.6 m) in 1990. Turfgrass color, quality, and root production increased with mowing height in 1989 and 1.0 unit in 1990. Turfgrass quality increased by 0.4 rating unit per mm increase in mowing height in 1989 and 1.0 unit in 1990. Root production at two soil depths of 75 to 150 mm and 150 to 225 mm increased with mowing height in 1990.

This investigation was conducted to assess the relationship of cell wall constituents of seven cool‐season turfgrass species to wear tolerance. The turfgrass literature contains no data of this nature. The percent total cell wall (TCW), lignocellulose (ADF), cellulose, hemicellulose, and lignin were determined on a gram dry weight and mg/dm2 basis. Species differed significantly in cell wall constituents for both methods of determination. The relative ranking of the species based on the content of various cell wall constituents expressed on a gram dry weight basis was as follows: Cascade chewings fescue (Festuca rubra var. commutata Gaud) > Pennlawn red fescue (F. rubra L.) and Kentucky 31 tall fescue (F. arundinacea Schreb.) > Manhattan perennial ryegrass (Lolium perenne L.) > Merion Kentucky bluegrass (Poa pratensis L.) > Italian ryegrass (L. multiflorum Lam.) > rough bluegrass (P. trivialis L.). However, the species ranked as follows when the cell wall components were expressed on mg/dm2 basis: Kentucky 31 > Manhattan and Merion > Pennlawn and Italian ryegrass > Cascade > rought bluegrass. Cell wall constituents reported on a g/dry wt. basis were not correlated individually to wear tolerance. However, the combined effects of TCW, ADF, cellulose, and lignin accounted for 96% of the observed wear tolerance variation among the seven turfgrass species studied. TCW, ADF, cellulose, and hemicellulose contents expressed as mg/dm2 were significantly correlated individually to wear tolerance. Their combined effects accounted for 97% of the variation in inter‐species wear tolerance. Total cell wall content expressed on a mg/dm2 basis accounted for 98% of the variation in wear tolerance among the seven turfgrass species. Cell wall constituents were found to increase significantly with plant maturity, with the exception of hemicellulose. TCW increased significantly during the period from July to September, but declined in all species during October. The TCW, ADF, cellulose, hemicellulose, and lignin contents of leaf blades were significantly less than for the leaf sheath for all species.