Influence of mowing frequency and mower sharpness on efficiency of PSII and antioxidant and carbohydrate metabolism of creeping bentgrass

Sports fields are mown primarily to provide a uniform surface for ball roll and bounce. However, mowing creates openings that facilitate water loss and entry points for pathogens, and increases susceptibility to other stresses. The objectives of our research were to identify physiological mechanisms that allow creeping bentgrass to tolerate close and frequent mowing. Plants often increase formation of reactive oxygen species (ROS) in response to wounding. Accumulation of ROS may damage macromolecules such as lipids, proteins, and nucleic acids. Damage to these macromolecules may result in reduced plant growth and vigor, or even death. Plants form enzymes to quench ROS and protect cells from oxidative damage. However, activities of ROS-scavenging enzymes often are reduced during stress. In our research, activities of the ROS-quenching enzymes catalase and ascorbate peroxidase were reduced in mowed grasses. Reduced activities of these enzymes may result in accumulation of ROS. However, no differences were observed in levels of lipid peroxidation between not-cut and mowed grasses, indicating that accumulation of ROS was not sufficient to cause severe oxidative stress. Although toxic at high concentrations, ROS may act as a component of a signal transduction pathway that acclimates not-stressed tissue to potential stress. It is necessary for grasses to regrow leaf tissue removed by mowing. Reserve carbohydrates often are hydrolyzed to generate carbon for respiration and to provide substrates for development of leaf and shoot tissue. Creeping bentgrass forms fructans as reserve carbohydrates. In our research, fructans were reduced in mown grasses compared to not-cut grasses. Glucose levels also were reduced in mowed grasses compared to not-cut grasses. Glucose likely was oxidized in the glycolytic pathway and respiration to provide energy for formation of new leaf tissue. It is important to remember that mowing is a stress and that mowing programs should balance agronomic requirements of grasses with sports play demands in order to produce uniform and visually appealing turf that is vigorous in growth

Psychodrama as a Personal Growth Experience : A programme for Teacher Trainees

Churchlands College was established in 1972 and was drawing up its first course submission when legislation separating teacher training institutions from the State Government Education Department was passed. With autonomy from the outset, staff were able to plan courses consistent with their own values and expertise. The College as a whole adopted a three-pronged approach to teacher preparation with programmes in curriculum and instruction methods, education and educational psychology and in personal and professional growth and development. Each department considered its possible contribution to these streams. I n considering its contribution to the personal growth programme for trainees the Psychology Department was in sympathy with recent trends in teacher education which focussed on the facilitative skills of the teacher and particularly on his ability to interrelate with his classroom group

Improving Grassland Quality in Communal Arable Lands in the Eastern Cape Province, South Africa

Overgrazing and shifting cultivation practise have severely degraded communal lands in the Eastern Cape of South Africa. Methods need to be developed to improve forage quality of grazing land, especially previously cultivated lands. The aim of the study was to investigate legume species to rehabilitate arable lands abandoned from cropping, to enhance their forage quality, productivity and ecological integrity. The study was conducted in seven communities within the Eastern Cape Province. This study showed that within the communal lands studied extensive areas have been cultivated and the majority of this land is now poorly utilised. Natural grasslands ploughed for cropping did not recover its original composition and therefore lost its primary ecological condition. New improved legume cultivars can significantly enhance forage quality on cultivated lands but individual species may not have the resilience to survive nutrient poor lands and variable winter rainfall. This study shows that using a mixture of annual and perennial legume species with different life traits contributed to enhanced forage quality, especially during winter when the nutritional value of grasses was low. Because of management constraints, pasture legumes cannot be seen as stand-alone pastures, but provide a mechanism to extend the forage potential of communal grazing lands

Genome sequence of the Ornithopus/Lupinus-nodulating Bradyrhizobium sp. strain WSM471

Bradyrhizobium sp. strain WSM471 is an aerobic, motile, Gram-negative, non-spore-forming rod that was isolated from an effective nitrogen-(N-2) fixing root nodule formed on the annual legume Ornithopus pinnatus (Miller) Druce growing at Oyster Harbour, Albany district, Western Australia in 1982. This strain is in commercial production as an inoculant for Lupinus and Ornithopus. Here we describe the features of Bradyrhizobium sp. strain WSM471, together with genome sequence information and annotation. The 7,784,016 bp high-quality-draft genome is arranged in 1 scaffold of 2 contigs, contains 7,372 protein-coding genes and 58 RNA-only encoding genes, and is one of 20 rhizobial genomes sequenced as part of the DOE Joint Genome Institute 2010 Community Sequencing Program

High-quality permanent draft genome sequence of the Mimosa asperata - nodulating Cupriavidus sp strain AMP6

Cupriavidus sp. strain AMP6 is an aerobic, motile, Gram-negative, non-spore-forming rod that was isolated from a root nodule of Mimosa asperata collected in Santa Ana National Wildlife Refuge, Texas, in 2005. Mimosa asperata is the only legume described so far to exclusively associates with Cupriavidus symbionts. Moreover, strain AMP6 represents an early-diverging lineage within the symbiotic Cupriavidus group and has the capacity to develop an effective nitrogen-fixing symbiosis with three other species of Mimosa. Therefore, the genome of Cupriavidus sp. strain AMP6 enables comparative analyses of symbiotic trait evolution in this genus and here we describe the general features, together with sequence and annotation. The 7,579,563 bp high-quality permanent draft genome is arranged in 260 scaffolds of 262 contigs, contains 7,033 protein-coding genes and 97 RNA-only encoding genes, and is part of the GEBA-RNB project proposal

High-quality permanent draft genome sequence of the Mimosa asperata - nodulating Cupriavidus sp strain AMP6

Cupriavidus sp. strain AMP6 is an aerobic, motile, Gram-negative, non-spore-forming rod that was isolated from a root nodule of Mimosa asperata collected in Santa Ana National Wildlife Refuge, Texas, in 2005. Mimosa asperata is the only legume described so far to exclusively associates with Cupriavidus symbionts. Moreover, strain AMP6 represents an early-diverging lineage within the symbiotic Cupriavidus group and has the capacity to develop an effective nitrogen-fixing symbiosis with three other species of Mimosa. Therefore, the genome of Cupriavidus sp. strain AMP6 enables comparative analyses of symbiotic trait evolution in this genus and here we describe the general features, together with sequence and annotation. The 7,579,563 bp high-quality permanent draft genome is arranged in 260 scaffolds of 262 contigs, contains 7,033 protein-coding genes and 97 RNA-only encoding genes, and is part of the GEBA-RNB project proposal

Genome sequence of the Lebeckia ambigua-nodulating 'Burkholderia sprentiae' strain WSM5005T

"Burkholderia sprentiae" strain WSM5005(T) is an aerobic, motile, Gram-negative, non-sporeforming rod that was isolated in Australia from an effective N-2-fixing root nodule of Lebeckia ambigua collected in Klawer, Western Cape of South Africa, in October 2007. Here we describe the features of "Burkholderia sprentiae" strain WSM5005T, together with the genome sequence and its annotation. The 7,761,063 bp high-quality-draft genome is arranged in 8 scaffolds of 236 contigs, contains 7,147 protein-coding genes and 76 RNA-only encoding genes, and is one of 20 rhizobial genomes sequenced as part of the DOE Joint Genome Institute 2010 Community Sequencing Program