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The Effect of Selfing on Trifolium alexandrinum Measured in Conditions of Interference Among the Plants
Full text linkAfter the constitution of the cv Sacromonte the breeding work on berseem (Trifolium alexandrinum) at the Forage Crop Institute of Lodi was slowed. A renewed interest in nitrogen fixing legumes in recent years has led to a program aimed at reevaluating the berseem clover. Today this crop is utilized not only in South Italy (autumn sowing) but in North Italy as well and in some Central European countries (spring sowing). The greatest utilization is in Egypt where berseem is grown either for forage crop or for green manure crop, usually preceding cotton or summer vegetables
Effects of Acid Soil Selection on Agronomically Important Traits in Alfalfa
Full text linkAcid soils and their related toxicities are found in every continent of the world. Since liming and fertilization rarely overcome subsoil acidity, poor rooting usually results when growing sensitive legumes such as alfalfa ( Medicago sativa L.). Subsoil liming increased alfalfa yield 46 % over conventionally limed controls indicating deeper rooting achieved through an ability to overcome subsoil toxicity significantly enhanced stand life and productivity (Bouton et al., 1986). If acid soil tolerance could be incorporated into new multiple-pest resistant cul ti vars without loss of their desirable traits, farmers may realize the benefits of any new alfalfa cultivar. The purpose of this investigation therefore was to determine the success of recurrent selection for developing acid soil tolerant alfalfa by monitoring changes in forage yield and disease resistance as well as acid soil tolerance
Continuous Machine Line for Grassland Management on Slopes in Czechoslovakia
Full text linkPermanent grass covers in Czechoslovakia are to a great extent spread in sloping and rolling countryside. From the total area presenting 1,672 thousand hectares, 240 thousand ha are stretched on slopes with a gradient of 16 to 22 degrees. Research has shown that from 35 to 48 per cent of these pieces of land arc of size less than 10 ha and there are 75 per cent of intensive pastures with size smaller than 6 ha in typical mountainous regions of Czechoslovakia. Mechanization of grass picking on slopes is effected by specific features predetermined by geographical conditions and requirements of safe operation of machines. As in Austria and Switzerland, the main reason for this adaptation is the complicated configuration of mountainous regions, the use of unsuitable« plain» mechanization causing a lot of tragic accidents at work(Sieg, 1981). Complication of natural conditions comparable with those of Alpine countries has motivated also Czechoslovakia to start development of special mechanization for pasture management on hillsides
On the Cultivation and Utilization of Floret Silvergrass (Miscanthus floridulus) in the Southern Area of China
Full text linkThe plant genus Miscanthus (silvergrass) includes eight species and one variety in China. In the tropical and subtropical area of south China, the silvergrass distributed widely includes the following seven species : Floret silvergrass ( Miscanthus floridulus), Chinese silvergrass ( M. sinensis), Sugary silvergrass ( M. sacchariflorus), Short-hair silvergrass ( M. brevipilus j, Eulalia silver grass ( M. eulalioides), Szechuan silvcrgrass ( M. szechuanensis), Nepal silvergrass ( M. nepalen�� sis). One of them, Floret silvergrass, is the widest in distribution and the highest in economical value, and plays a most important role in the animal husbandry, light industry and the conservation of water and soil; up to now, it has been cultivated widely and gradually become the semi-cultivated type plant in Guizhou and Hunun provinces of China. Floret silvergrass is mainly distributed between the north latitudes 18°10\u27-34°, and the cast longitudes 98°20\u27-121°40\u27 in China; in Anhui, Zhejiang, Hunun, Hubei, Jiangxi, Yunnan, Sichuan, Guizhou, Guangdong, Guangxi, Fujian, Floret silvergrass can be found in the plant catalogue of these provinces and countries and on the base of the reports, it also occurs in Hainan island and Taibei province. In accordance with the description of the vegetation in Hainan island by the Grassland Institute of the Academy of Agricultural Science of China:\u3c\u3c Floret silvergrass is a common species in the mcsophytic tropical grassland and hilly tropical grassland, where it can grow well in the conditions of the iron red clay and hilly yellow cla
Development of Measures for Highway Criticality Assessment
Full text linkExisting network criticality assessments, often biased towards heavily used highways in populous areas by incorporating traffic and sociodemographic attributes, can lead to an underestimation of the vital role of rural infrastructure. Consequently, rural highways, particularly low-volume roads, often receive less consideration despite their critical role in network connectivity and local access to services and economic opportunities. To address this, we develop a criticality framework based on the egalitarian principle, which prioritizes equitable consideration of all network links regardless of traffic volume or population density, comprising two complementary measures. First, the normalized betweenness centrality quantifies a road\u27s relative importance in efficiently connecting the local network by measuring the percentage of origin-destination pairs utilizing it within its neighborhood. Normalized betweenness centrality is employed to capture the essential role of rural roads in local connectivity, even with lower traffic volumes. Second, detour importance, an aggregate metric, assesses a road\u27s contribution to network redundancy by tracking the percentage of trips diverted to it when other critical roads are disrupted. Detour importance further highlights their significance by quantifying their contribution to network resilience when primary routes are unavailable, a crucial aspect often overlooked in assessments focused solely on high-traffic corridors. To ensure accurate calculation of these measures, particularly in capturing the nuances of travel within local and potentially less congested rural networks, we leverage ubiquitous probe vehicle data for real-world travel times, which is central to our shortest-path analysis. The results from a Kentucky case study confirm the effectiveness and practical feasibility of our framework for large-scale applications due to its efficient algorithms and reliance on readily available data. This framework offers a more equitable approach to network criticality assessment, providing valuable insights for transportation planning and investment decisions that better reflect the importance of rural infrastructure for connectivity and community access
Mineral Supplementation and Phosphorus Fertilizer Application on Native Pastures in North-East Argentina
Full text linkExtensive cattle production systems in north-east Argentina are based on the use of native pastures. One of the most important limiting factors to improve production is the acute phosphorus deficiency of soils and pastures. A large experiment was set up to study the effect of phosphorus fertiliser and mineral supplementation on the liveweight gain of steers of 2 ages grazing native pastures. Supplementation with a mixture of bone meal and salt, residual effect of P fertilisation, and both treatments applied together increased the annual animal live-weight gain by 60, 66 and 106%, respectively. The response of younger steers to fertiliser and supplementary P and salt was higher than that of the older steers
Effect of Supplementation on Pasture Selection by Grazing Steers. I. Quality of Ingested Forage
Full text linkThree oesophageal fistulated Hereford steers (average live weight 304 kg) were supplemented throughout a trial at 0, 0.7 or 1.4% of live weight, with a mixture of 90% ground maize and 10% sunflower expeller. Adaptation and sampling periods were 7 and 4 days respectively. Steers were allocated randomly to 4 Agropyron•dominated pastures of 1800, 2000, 8200 and 8900 kg OM/ha and leaf percentage of 5.8, 28.9, 23.2 and 14.0, respectively. Fistula samples were taken once daily, air dried at 60°C and analysed. Supplementation significantly (P\u3c0.05) affected DM digestibility, which was 51.3, 54.7 and 57.2 for 0, 0.7 and 1.4% levels, respectively. Nitrogen and cell wall content differences were not detected. It appears that supplemented steers preferred pasture components with the highest digestibility
Major Beef Production Gains from Commercial Rain-Fed Leucaena-grass Pastures in Central Queensland, Australia
Full text linkCommercial leucnena-grass pastures in central Queensland increased from 24 ha in 1979 to about 20 000 ha in 1992. Since 1986 the exotic leucaena psyllid devastated leucaena (Leucaena leucocepliala) production along the humid coastal areas but not in the subcoastal plantings where the hot dry atmosphere controls the psyllid populations. The introduced rumen bacteria to detoxify DHP has enhanced the performance of cattle grazing leucaena. Unfertilised rain-fed leucaena-grass pastutes with leucaena rows 5-10 m apart have given annual steer live-weight gains of more than 250 kg consistently at stocking rates around 1-1.5 ha/steer. One cattleman with about 500 ha of leucaena-grass pastures has recorded 317 kg live-weight gain/ha in a year. Producing prime cattle at 100-120 cents/kg live weight on rainfed leucaena-grass pastures is more lucrative than grain growing. The profitability of producing young top quality beef will encourage more rapid adoption of leucaena pastures as permanent alley grazing or alley cropping. An area of 120 000 ha of leucaena in central Queensland can be expected in the next decade
Southern United States Forest Range Management: History and Development
Full text linkThe history and development of forest range management in the southern USA are discussed, including influences of domestic livestock, wildlife, forestry, research, education and societies, Domestic cattle entered the USA in 1521; since then grazing the piney woods has been common. By the early 1930s, old growth timber was harvested from Texas to Florida and South Carolina. Fire control legislation helped reforestation to peak in 1959. This forced many cattlemen out of business owing to the fast-growing pines. Wildlife declined with colonisation but many populations were reestablished after World War II. Public agencies, universities, and the Society for Range Management helped develop southern range management programmes from the mid-1940s to the 1990s
Selection of Sylosanthes spp. for the Cerrados of Brazil
Full text linkImproved seed yield and leaf retention during the dry season coupled with anthracnose resistance were recorded among mid-season flowering progenies of intervarietal hybrids of Stylosantheses guianensis var. vulgaris x var. panciflora. Mineirao, a late-flowering accession of S. g11ia11e11sis var. vulgaris, displayed similar agronomic traits, but produced lower seed yields. Venezuelan accessions of S. capitata, and a binary mixture of S. capitata-S. ,nacrocepllala showed field resistance to anthracnose. Inter- and intraspecific variation for resistance to anthracnose disease was demonstrated by inoculation with virulent local and introduced pathotypes of Colletotrichum gloeosporioides. The development from these heterogeneous populations of cultivars with desirable agronomic traits seems feasible