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Major Beef Production Gains from Commercial Rain-Fed Leucaena-grass Pastures in Central Queensland, Australia
Get PDFCommercial 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
Get PDFThe 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
Get PDFImproved 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
Development of Rhizoma Peanut for Forage in Lower South, USA
Get PDFRhizoma (perennial) peanut (Arachiis glabrata Benth.) (RP) is n perennial, warm-season legume, adapted to well-drained soils of humid tropics and subtropics. It is grown in Florida and warmer portions of the south-eastern USA up to about 32°N. Cultivar Florigraze was released in 1978 and cv. Arbrook in 1986. Commercial hectarage of RP has increased about 40% annually to approximately 2000 ha in 1992. Propagated vegetatively from rhizomes, RP Is slow to establish. Rhizoma peanut is drought-tolerant, persistent, grows well on droughty, low-fertility soils, requires moderate to excessive soil drainage and requires no N and usually no P fertiliser. It is longlived, highly resistant to diseases, insects and nematodes, and produces high quality palatable forage similar to alfalfa (Medicago saliva L), Rhizoma peanut can be grazed or harvested as hay, haylage and silage. Continuous interaction between researchers, extensionists and producers has developed the technology needed for growing RP
Recurrent Selection for Partial Resistance to Anthracnose Disease in Shrubby Stylo (Stylosanthes scabra)
Get PDFThree cycles of crossing have been completed in a recurrent selection programme for partial resistance to anthracnose disease of shrubby stylo (Stylosanthes scabra) In a field study of a subset of 40 F2 populations from the first cycle, highly significant differences (P\u3c0.001) in anthracnose resistance were found for both male and female effects and for the female x male interaction, In a subsequent F3 progeny test of 99 families selected for disease resistance and yield, 92 of the families were resistant to highly resistant with leaf damage \u3c1% (cf, \u3e50% damage for the susceptible cultivar, Fitzroy). Strong discrimination for resistance was also obtained in a second subset of 23 F2 populations using combined glasshouse and field selection for resistance. Further improvement in anthracnose resistance was achieved in the second and third cycles of recurrent selection. The broadly based resistance of selections from the third cycle should ensure stability of field resistance to the damaging anthracnose fungus
Effects of Phosphogypsum, Phsophorus and Lime on Andropogon gayanus Kunth
Get PDFThere are several factors which determine the low animal productivity in the tropics. Among these factors, inadequate nutrition is the most limiting one followed by the low natural fertility and high acidity of the soils in these regions. Previous findings have shown important soil nutrient deficiencies in some Brazilian cerrado soils. Malavolta (1952) demonstrated sulfur (S) deficiencies, while Werner et al. (1967) found plant response to S. Responses to phosphorus addition are very common in this kind of soil and in tropical America there are rates of phosphorus being applied, which sometimes are uneconomical for the formation and maintenance of pastures. The combination among tolerant varieties to the low phosphorus disponibility, the correct application of phosphatic fertilizers and the correction of the soil acidity, to reduce phosphorus fixation, would be an effective mean for its economical utilization in many tropical soils with high fixing capacity. In many cases, tropical grasses have shown little or no response to liming (Emrich, 1967). Being adapted to high acidity, they respond only to calcium and/or magnesium fertilization, when used at rates that are not enough to affect pH and the exchangeable aluminium (Ciat, 1977); however, there is a differential tolerance to soil acidity among forages, each species or variety in the same species having a different behavior. The purpose of this paper was to investigate possible deficiencies and responses of andropogon grass to rates of sulfur, phosphatic fertilization, and liming on cerrado soil
Determination of Predictive Zones for the Evaluation of Herbage Grasses in Cuba
Get PDFRegional studies that evolve a high quantity of environment are made nowadays in order to define the behaviour of a genotype in different environments, but the workers of introduction programmes can not prove their varieties in all environments. Therefore, it is necessary to select a wide range to represent production conditions. This topic has been studied by several writers (Rambling et al., 1980; Brown et al., 1983). The objective of our study is to reduce test sites due to the high source in income needed in these studies
Genotypic Differences in Seedling Vigor in Sericea Lespedeza
Get PDFSlow seed germination and poor seedling establishment have been considered major problems in sericea lespedeza [Lespedeza cuneata (Dumont de Courset) G. Don.], a summer perennial legume grown in the southeastern United States for forage and soil conservation (Logan et al., 1969). Wright et al. (1978) considered sericea lespedeza a nonaggressive species because of the low number of seedlings that emerge and the long time needed for emergence as compared to other species. Hoveland et al. (1971) indicated that sericea lespedeza seedlings are weak and compete poorly with weeds. Recommended planting time of sericea is early spring as soon as there is not a risk of a heavy frost. In Alabama, this period is from March to early April (Ball and Donnelly, 1985). The estimated daylength during this time of year in Alabama is between 11 and 13 h (Anonymous, 1984). Pieters (1939) first observed that the growth of sericea lespedeza plants was strongly affected by daylength. Similar results were obtained by Bates (1955), who found that 5 cm plants exposed to daylengths less than 13 h grew very little. The objectives of the present study were to measure the influence of temperature and daylength on early growth of sericea lespedeza genotypes
Contribution a l’etude des Especies Spontanees du Genre Trifolium L. en Algerie: Repartition en Fonction de Quelques Facturs du Milieu
Get PDFEn Algerie, le deficit chronique en lait et viande est du essentiellement a une mauvaise alimentation du troupeau. Les fourrages cultives occupent une faible superficie par rapport a !\u27ensemble des cultures herbacees et l\u27essentiel de l\u27alimentation du cheptel repose sur Jes jacheres et Jes parcours. Le genre Trifolium, sur lequel s\u27est porte notre inten��t, comporte plusieurs especes spontanees dont le role fourrager est certain. Cependant, ii est indispensable, comme cela a ete fait pour Jes genres Medicago, Scorpiurus et Hedysarum, de definir Ia repartition des differentes especes de ce genre en fonction des facteurs du milieu. Ceci constitue le but de cet article