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Evaluation of Annual Medics and Subclovers in Oklahoma
Get PDFOklahoma has a continental climate with cold winters and a late spring or early-summer rainfall peak. Kneebone (1959) found little justification for attempts to use native legumes for revegetation purposes in western Oklahoma rangelands. Denman et al. (1961) evaluated 54 genera, 216 species and 1,366 entries of legumes in Stillwater, Oklahoma between 1951 and 1959. They concluded that only alfalfa and some vetches (Vicia spp.) had any forage potential. Most clovers and medics failed to survive the winter cold.
Subclover is largely but not wholly Mediterranean in its distribution (Morley, 1961) and has been grown on limited hectarages in the southeartern US and the Texas gulf coast region. Donald (1960) pointed out that genetic variation in subclover collected from fringe areas of the Mediterranean basin broadened the area of adaptability for many cultivars but few recent studies in the Southern Great Plains have evaluated any of the many new cultivars commercially available
Basic Aspects, Objectives and Preliminary Results of a Subterranean Clover Improvement Program in Sardinia (Italy)
Get PDFThe process of extended agronomical rehabilitation of the heavily deteriorated pastures, activated in Sardinia in the 1970\u27s, has been largely supported by the introduction of subterranean clover (Trifolium subterranuem L. sensu lato) as a cultivated plant in the island. Although this annual self-reseeding species has readily become the most widely sown pasture legume in Sardinia, the broadscale use of imported varieties has not always been an unqualified success, particularly in terms of long-term persistence. Therefore, the need to define clearly the particular combination of characters contributing to adaptation in Sardinia, and to develop local varieties specifically adjusted to Sardinian climatic and edaphic conditions, has been invoked for a better exploitation of the potentialities of subterranean clover. According to these requirements, a selection program was activated in the early 1980\u27s. Some basic aspects, objectives and preliminary results of this program are summarized in this paper
Analysis of Variation in Sainfoin (Onobrychis viciifolia) by Clustering
Get PDFSainfoin (Onobrychis viciifolia) is a forage legume that attracts interest due to its feeding value to ruminants. This is based on factors such as hight voluntary intake, non-bloating and protein protection, all of which appear related to the concentration of condensed tannins in the plant tissue (Ulyatt et al., 1977). Agronomic difficulties with sainfoin such as low yield and poor persitence show a lack of consistency between experiments which seem to be due, in part, to the level of heterogeneity displayed by the available sainfoin cultivars and germplasm (Fortune and Withers, 1980; Rumball, 1982). By permitting examination of the relationships between measured variables, multivariate techniques offer a method of grouping individuals into lines (Chatfield and Collins, 1980). This is frequently a requirement of plant breeders. The objective of this work was to examine the pattern of variation in sainfoin grown under controlled environmental conditions. The numerical approach was to examine the variability, simplify the array of data collected, and to consider the effective use of the reduced data
The Effect of Selfing on Trifolium alexandrinum Measured in Conditions of Interference Among the Plants
Get PDFAfter 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
Get PDFAcid 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
Get PDFPermanent 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
Get PDFThe 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
Get PDFExisting 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
Get PDFExtensive 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
Get PDFThree 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