Public attention is being increasingly focused on the environmental impact and management costs of turfgrass areas such as lawns for schools, parks, and homes. The objectives of this study were to: (i) identify grass species adapted to low‐input environments (limited water, no fertilizer or pesticides after establishment) in the North Central Region (NCR) of the USA; and (ii) evaluate these species for turfgrass quality under mowed and non‐mowed conditions. Low‐input turf trials of 12 grass species were established at eight locations and evaluated for turf quality over two years. Plots were mowed monthly at either 5.1 or 10.2 cm or not mowed. Hard fescue (Festuca brevipila Tracey), colonial bentgrass (Agrostis capillaris L.), tall fescue (Festuca arundinacea Schreb.), and sheep fescue (Festuca ovina L.) performed well at most locations at the 5.1 and 10.2‐cm mowing heights. Several other species were also evaluated: tufted hairgrass [Deschampsia cespitosa (L.) P. Beauv.], hybrid bluegrass (Poa arachnifera Torr. × Poa pratensis L.), meadow fescue [Schedonorus pratensis (Huds.) P. Beauv.], prairie junegrass [Koeleria macrantha (Ledeb.) Schult], crested wheatgrass [Agropyron cristatum (L.) Gaertn.], alkaligrass [Puccinellia distans (Jacq.) Parl.], blue grama [Bouteloua gracilis (Willd. Ex Kunth) Lag. Ex Griffiths], and crested dogstail (Cynosurus cristatus L.).

Rhizomes of zoysiagrass (Zoysia spp.) were subjected to controlled freezing tests in Jan. and Mar. 1993 and 1994 to determine their low-temperature tolerance. In 1994, `Belair', `Korean `Common', `Meyer', and `TGS-W10' rhizomes survived temperatures as low as -18 °C, while rhizomes of `Sunburst' survived -14 °C. `Cavalier', `Crowne', `Palisades', `Emerald', and `El Toro' were killed at -10 °C or warmer temperatures. Entries surviving exposure to -14 to -18 °C in 1994 controlled freezing tests received post-winter survival ratings in the field of 6.7 to 8.7 (9 = 100% green). Entries killed at higher freezing test temperatures were slower to recover after winter in the field, with ratings of 2.0 to 3.0. Shoot number produced after freezing was a better measurement for assessing low temperature tolerance than was shoot mass. Controlled freezing tests, using regrowth as a measure of hardiness, appear to be useful for identifying low temperature tolerance of zoysiagrasses in the early years of a field study.

Glyphosate resistance was found in a rigid ryegrass population in northern California. A sample of the resistant plants were collected and grown under greenhouse conditions. The objective of this study was to evaluate glyphosate resistance in the progeny of the collected plants by recurrent selection, obtain the homozygous resistant and sensitive lines to establish dose-response curves, and to determine the inheritance of glyphosate resistance in rigid ryegrass. Diverse levels of resistance were observed in the first generation with survival of 89, 59, 45, and 9% from glyphosate at 1x, 2x, 4x, and 8x respectively, where x = 1.12 kg ha−1isopropylamine salt of glyphosate. Clones of plants that died from 1x were allowed to produce seed and were further subjected to recurrent selection to generate the most sensitive plants (S lines), which died from 0.125x glyphosate. The most resistant plants (R lines) were generated from the survivors receiving 8x glyphosate. The ratio between I50rates for the glyphosate resistant and the glyphosate sensitive plants was > 100-fold. The R and S lines were crossed reciprocally and F1progeny of both (R × S) and (S × R) showed intermediate resistance. These survived up to 2x glyphosate. The F2progeny were generated by intercrossing of F1plants. The ratio of sensitive, intermediate, and resistant plants in the F2population before the treatment of glyphosate at 0.125x followed by 8x was 1 : 16, 14 : 16, and 1 : 16 respectively, which corresponded to the Mendelian segregation ratio of two genes. The results indicated that the inheritance of glyphosate resistance in rigid ryegrass from California appeared to be nuclear, incompletely dominant, multigenic, and pollen-transmitted with no indication of maternal inheritance.

Bentgrasses (Agrostis spp.) are widely occurring temperate grasses with more than 220 species that represent a vast resource for genetic improvement of turfgrass cultivars. Bentgrasses are normally outcrossing species and exhibit many ploidy levels. Difficulties in morphological characterization, which are largely subjected to environmental influences, have resulted in many synonymous species and uncertainties in phylogenetic relationships. To study the genetic diversity and relationships between bentgrass species, 40 accessions from the USDA's germplasm collection representing 14 species of Agrostis from twenty countries were investigated by fluorescence‐labeled amplified fragment length polymorphism (AFLP) analysis. Four hundred AFLP markers from five chosen primer combinations were used to differentiate between bentgrass accessions of a bulk of 25 genotypes per accession. Genetic similarities between accessions ranged from 0.62 to 0.98 showing no duplication in the collection and a high level of diversity in Agrostis Both principal component analysis and Unweighted Pair Group Method with Arithmetic Mean (UPGMA) dendrogram clearly distinguished seven groups. Genetic relationships between diploids and other polyploids were revealed in the cluster groupings.

Advances in plant genomics have permitted the analysis of several members of the grass family, including the major domesticated species, and provided new insights into the evolution of the major crops on earth. Two members, colonial bentgrass (Agrostis capillaris L.) and creeping bentgrass (A. stolonifera L.) have only recently been domesticated and provide an interesting case of polyploidy and comparison to crops that have undergone human selection for thousands of years. As an initial step of characterizing these genomes, we have sampled roughly 10% of their gene content, thereby also serving as a starting point for the construction of their physical and genetic maps. Sampling mRNA from plants subjected to environmental stress showed a remarkable increase in transcription of transposable elements. Both colonial and creeping bentgrass are allotetraploids and are considered to have one genome in common, designated the A 2 genome. Analysis of conserved genes present among the ESTs suggests the colonial and creeping bentgrass A 2 genomes diverged from a common ancestor approximately 2.2 million years ago (MYA), thereby providing an enhanced evolutionary zoom in respect to the origin of maize, which formed 4.8 MYA, and tetraploid wheat, which formed only 0.5 MYA and is the progenitor of domesticated hexaploid wheat.

Availability of newer, more competitive cool-season grasses has renewed interest in persistent, balanced warm-and cool-season species mixtures for sports turf. In this Missouri study, one-time overseedings of blends and mixtures of Kentucky bluegrass (Poa praJensis L.), perennial ryegrass (Lolium perenne L.), Chewings fescue (Festuca rubra L. subsp. commutlltll Gaud.), hard fescue (Festuca longifolia Thuill.), and creeping red fescue (Festuca rubra L. subsp. rubra Gaud.) were made on established plots of KSU S-16 and 'Midiron' bermudagrass [Cynodon dactylon (L.) Pers.). One-half of each plot was subjected to simulated traffic beginning 18 mon after overseeding, using a modified Brinkman traffic simulator. Quality of four mixtures (bermudagrass + Kentucky bluegrass, bermudagrass + perennial ryegrass, bermudagrass + perennial ryegrass + Kentucky bluegrass, and bermudagrass + perennial ryegrass + Kentucky bluegrass + Chewings fescue) remained in an acceptable range at most observation dates after 3 yr of spring-and-fall traffic. Bermudagrass control plots were in poor or marginal condition at most observation dates during the same period. Bermudagrass plus fine leaf fescues were severely damaged by simulated traffic. Quality of turf receiving no simulated traffic was generally good and varied seasonally in response to changing environmental conditions. Higher-impact absorption measurements, based on peak deceleration (maximum g) on turf receiving simulated traffic vs. no traffic, were consistent with decreasing thatch and verdure. Traction (in N·m) decreased on trafficked turf as thatch and aboveground biomass deteriorated. Kentucky bluegrass and perennial ryegrass dominated mixtures with bermudagrass after 3 yr, and showed good tolerance to simulated traffic.

Rapid, inexpensive, and accurate procedures are required for predicting in vivo dry matter digestibility (DMD) offorages, particularly in a forage breeding program when many samples may be analyzed simultaneously. The primary objective of this study was to investigate the relationships of several cellulase digestion procedures to in vivo DMD, in vitro DMD using rumen liquor, neutral detergent fiber (NDF), acid detergent fiber (ADF), acid detergent lignin (ADL), and hemicellulose for several temperate forage species. A cellulase solution was produced by culturing the conidia from Trichoderma reesei Simmons in a mineral medium containing 10 g L -• cellulose. Apparent activity of the cellulase solution was determined by digesting cool season forages of known DMD and solka floc substrate. Fortytwo dried cool season forages which previously had been evaluated for per cent NDF, ADF, ADL, in vitro DMD using rumen liquor, and in vivo DMD using sheep were subjected to different cellulase digestion procedures. Correlations between the various cellulase DMD techniques and in vivo DMD were highly significant (p < 0.01) and ranged from 0.89 to 0.97. Correlations of the cellulase in vitro DMD techniques and NDF, ADF, ADL, and hemicellulose were negative and similar in magnitude to the same parameters ,when correlated to in vitro DMD using rumen liquor. The data suggested that the in vitro DMD obtained by using a prepared cellulase solution was an excellent predictor of in vivo DMD and the digestion was similar to that when digesting forages with rumen liquor. AdditioiUII index words: Trichoderma reesei Simmons, Orchardgrass (Dactylis glomerata L.), Smooth bromegrass (Bromus inermisLeyss.), Timothy (Phleum pratense L.), Alfalfa (Medicago sativa L.), In vivo dry matter digestibility, In vitro dry matter digestibility, Neutral detergent fiber, Acid detergent fiber, Acid detergent lignin, Hemicellulose.~~ontribution from the Missouri Agric. Exp. Stn., Journal S1:ries no. 9785.

In plants, low temperatures can activate the CBF cold response pathway playing a prominent role in cold acclimation by triggering a set of cold-related gene expressions. CBF homologous gene, designated as LpCBF3, from a cold-tolerant perennial ryegrass (Lolium perenne L.) accession was identified. It carries the sequences for nuclear localization signal (NLS), AP2 DNA-binding domains and an acidic activation present in most of the plant CBF proteins. Southern analysis indicated the presence of three homologs of LpCBF3 gene in perennial ryegrass genome, and only one amino acid variation in LpCBF3 protein between cold-tolerant and -sensitive perennial ryegrass accessions. In their putative promoter regions, some differential regions were found. Northern blotting and RT-PCR analysis found that LpCBF3 reached the highest expression after 1.5 h of cold treatment (4 degrees C). The COR homologous gene, a downstream gene of CBF, can be expressed in the plant stem of cold-tolerant perennial ryegrass accessions without cold treatment. Without cold treatment, the COR gene cannot be activated in cold-sensitive perennial ryegrass accessions. Cold treatment can prompt expression levels of COR homologous genes in both perennial ryegrass accessions. In transgenic Arabidopsis, the overexpression of LpCBF3 with the 35S promoter resulted in dwarf-like plants, later flowering and greater freezing tolerance.