Adaptation Responses Of Tropical Grass-Legume Associations To Acid Soils,
2024
CIAT
Adaptation Responses Of Tropical Grass-Legume Associations To Acid Soils, I M. Rao, M A. Ayarza, R J. Thomas, M J. Fisher, C E. Lascano, V Borrero
IGC Proceedings (1977-2023)
A greenhouse study was conducted to test the influence of soil texture (clay loam and sandy loam) and soil fertility status (low and high) on plant growth, dry matter (DM) partitioning between shoots and roots, proportion of legume roots in an association, root length density and net photosynthesis of 3 tropical grass + legume associations: Brachiaria dictyoneura + Arachis pintoi; Andropogon gayanus + Centrosema acutifolium; and Andropogon gayanus + Stylosthes capitata adapted to acid soils. Both soils are characterised by low pH and high aluminium saturation. The sandy loam soil had lower levels of soil organic matter and total nitrogen …
Rate Of Decomposition And Release Of Nutrients From Litter In A Heteropogon Contortus-Bothriochloa Bladhii Dominant Native Pasture,
2024
Brian Pastures Research Station
Rate Of Decomposition And Release Of Nutrients From Litter In A Heteropogon Contortus-Bothriochloa Bladhii Dominant Native Pasture, Deryk G. Cooksley, J H. Prinsen, C J. Paton, A T. Lisle
IGC Proceedings (1977-2023)
Litter dry matter (DM) decomposition and nutrient (N, P, K and S) release were measured for 8, 6-monthly periods in south-eastern Queensland. Litter collected from native paslure growing on a range of soil types was hammer milled, and buried in nylon bags at the collection site, Moisture and (tn a lesser extent) temperature had a greater effect on DM disappearance from nalive pasture litter than its chemical composition or the soil type. A simple index of litter disappearance was derived from average air temperature and surface (0-10 cm) soil water. Based on long-term rainfall and temperature data, 24.8% of litter …
Nitrogen Use Efficiency By Chloris Gayana During The Cold Season On The Island Of La Reunion,
2024
CIRAD-Elevage
Nitrogen Use Efficiency By Chloris Gayana During The Cold Season On The Island Of La Reunion, Gilles Mandret, A Ourry, P F. Chaballier, J Salette
IGC Proceedings (1977-2023)
Cattle breeding improvement at the island of la Reunion (Indian Ocean) had to face 2 major problems: increase the production of heifers and improve forage production. Deficit of forage production will require intensification of farming practices and more particularly higher nitrogen inputs in grassland. Moreover, the great pedoclimatic diversity associated with altitude variability implies use of both temperate and tropical species with or without irrigation. Since 1990 experiments have been undertaken with 1SNH4 15NO3 -fertilised Chloris, gayana, Pennisteum clandestinum, and Lolium hybridum during wet and dry seasons. The C, gayana stand was irrigated when necessary and porous ceramic cups …
Soil Factors And Grassland Type Relationships In The Subhumid Zone Of Northern Benin,
2024
Universite Nationale du Benin
Soil Factors And Grassland Type Relationships In The Subhumid Zone Of Northern Benin, Brice Sinsin
IGC Proceedings (1977-2023)
Soil samples collected under different grassland vegetations were studied. Mineral components were closely related to organic matter (OM) level, which was significantly correlated with cation exchange capacity (CBC). OM had an estimated average CEC of 1.8 me./100 g soil. Total exchangeable bases depended on both organic and mineral components and pH. Exchangeable K and Na depended mostly on clay and silt fractions, Cluster and principal component analysis enabled recognition of 5 clusters each grouping different grassland vegetation types. This confirms that soil factor analysis supports the field descriptions of the study soils but is inadequate to discriminate floristic composition at …
Efficient Nitrogen Fertilizer Strategies For Tropical Beef And Dairy Production Using Summer Rainfall And Soil Analysis,
2024
Department of Primary Industries
Efficient Nitrogen Fertilizer Strategies For Tropical Beef And Dairy Production Using Summer Rainfall And Soil Analysis, M A. Gilbert, N M. Clarkson
IGC Proceedings (1977-2023)
Nitrogen (N) deficiency is a major limitation to growth of pastures in tropical and subtropical regions. In the tropics and subtropics of north-eastern Australia, grass yield is curvilinearly related (R2=0.75) to summer rainfall and the rate of N fertiliser. Data from a range of grazing experiments also indicate that beef and dairy production (kg/ ha) are related to N fertiliser rate in a curvilinear manner; production is near optimum at N rates of 250-300 kg N/ha/year, when summer rainfall is >1000 mm. Given the importance of summer rainfall and N fertiliser, climatic analysis can enhance the usefulness of N fertiliser …
Effects Of Tillage On Soil Nitrogen And Growth Of Three Rhodes Grass (Chloris Gayana Kunth) Cultivars On A Typical Haplustol,
2024
Catholic University of Cardoba
Effects Of Tillage On Soil Nitrogen And Growth Of Three Rhodes Grass (Chloris Gayana Kunth) Cultivars On A Typical Haplustol, M F. Barbero, C B. Loza, P C. Faustinelli
IGC Proceedings (1977-2023)
In the northern part of the province of Cordoba (32°S), Argentina pasture production is limited by nitrogen availability. The work, using Rhodes ( Chloris gaya11a Ku nth) of 3 origins, evaluated the effect of various dates of surface tillage on the dry matter production and nitrogen content of 3 Rhodes grass cultivars: a local ecotype (Cordobes), cv. Samford and cv. Katambora. Dry matter and nitrogen production was increased in the 3 cultivars when the tillage was done before the rainy season.
Soil Quality And Its Management In Humid Subtropical And Tropical Environments,
2024
The Ohio State University
Soil Quality And Its Management In Humid Subtropical And Tropical Environments, R Lal, F P. Miller
IGC Proceedings (1977-2023)
The subtropical and tropical ecoregions of the world cover an extensive area of about 4900 million ha, and are characterised by deeply weathered soils derived from geologically old materials, In humid regions, the combination of high temperature and moisture has enhanced the rate and depth of weathering, accelerated leaching and led to the formation of acidic soils with low activity clays. The seasonally dry tropics extend over about 2475 million ha, characterised by savanna vegetation including a mixture of trees and grasses, In comparison with humid ecoregions, the grazing potential is high for soils and climate of the seasonally dry …
Origin And Regulation Of Nutrient Supply To Plants In Humid Tropical Grasslands,
2024
Laboratorie d'Ecologie des Sols Tropicaux Centre Orston
Origin And Regulation Of Nutrient Supply To Plants In Humid Tropical Grasslands, Patrick Lavelle, Michael J. Swift
IGC Proceedings (1977-2023)
Stocks and fluxes of carbon and nutrients ln tropical grasslands are determined by a suite of hierarchically organised factors.· Rain foll patterns and edaphic factors first determine the nature of the vegetation, the quantity and quality of organic inputs, and the relative allocation to the production of shoots or roots. Grazing by cattle or native herbivores, and fires, are other processes that significantly affect nutcient cycling. The nature and intensity of constraints exerted by these factors separate different types of tropical grasslands, i.e., savannas induced by the seasonality and limited abundance of rainfall, savannas induced by the poverty of soils …
Viability Of Grass-White Clover Swards For Dairying Production In The Uk,
2024
SAC
Viability Of Grass-White Clover Swards For Dairying Production In The Uk, J A. Bax, G.E J. Fisher
IGC Proceedings (1977-2023)
The potential of extensification to reduce production within the BC has increased interest in the use of white clover (Trifolium repens) for milk production. In a long-term system study to determine the potential of white clover, 2 herds of 70 cows were managed on either grass swards plus 350 kg N/ha/annum or on grass-white clover swards which received no inorganic N. Continuous grazing and up to 3 conservation cuts a year had no adverse effects upon clover contents in the mixed swards. Total silage OM yields/ha from the grass-white clover swards were 0,82, 0.81 and 0.96 of those …
Choosing A Forage System For The Future In Dairying Production In The Western Part Of France,
2024
Chambre d' Agriculture
Choosing A Forage System For The Future In Dairying Production In The Western Part Of France, Eric P. Gendron
IGC Proceedings (1977-2023)
A group of 25 dairy farms (44 ha, 38 cows, 7500 kg of milk/cow) was used for elaborating technical and economic references on dairy production systems in the department of Maine et Loire (western France), between 1986 and 1991. Changes in choosing a forage system began with the restriction of dairy production under EC rules introduced in 1984. Very intensive systems (over 10 000 kg of milk/ ha) no longer guaranteed that a better level of production per cow meant a better income for the farmer. After 5 years of study it was possible to propose 4 forage systems with …
Effect Of Grazing Order On Live-Weight Gain Of Young Female Beef Cattle,
2024
Universidade Federal do Rio Grande do Sul
Effect Of Grazing Order On Live-Weight Gain Of Young Female Beef Cattle, Jose Fernando Piva Lobato, Blas H.J Cristaldo Albospino, Fernando Rigo Magalhaves, Assan Ali Taher
IGC Proceedings (1977-2023)
In order to evaluate the daily live-weight gain and overall live weight of 2 groups of 30 female beef calves from weaning until 2 years of age, an experiment was run at Field Station al Federal University of Rio Grande do Sul, in Eldorado do Sul district. Group A was introduced to the paddocks first, and the animals were allowed to graze half the available pasture. These animals were then removed and group B was introduced and grazed the remaining available pasture, During the first (28 June 1990-19 October 1990), and second (12 June 1991-16 October 1991 ), winter-spring seasons, …
Animal Keeping By Grazing,
2024
Debrecen University of Agricultural Sciences
Animal Keeping By Grazing, I Vinczeffy, M Kota
IGC Proceedings (1977-2023)
This study calls attention to some important parameters and effects of the pasture and grazing, on the basis of our experiments carried out during the last 45 years.
Flood-Tolerant Pastures For Dairying In Northland,
2024
AgResearch, NZ
Flood-Tolerant Pastures For Dairying In Northland, P W. Woods, J N. Couchman, A O. Taylor
IGC Proceedings (1977-2023)
Much flood-prone land in Northland consists of fertile alluvial flats which are or could be used for dairy production. Heavy rainfall from subtropical cyclonic dislurbances have caused severe pastoral damage to these areas by flooding during late summer and early autumn. A range of pasture species were screened to ascertain plant surviv_al under depleted oxygen levels and warm temperatures which occur in flood water during summer. Subtropical grasses screened tended to survive immersion better than temperate species. Creeping grasses such as Hemarthria altissima and Paspalum distichum were more tolerant than P. dilatatum. Of the temperate species, Phalaris arundinacea, Phleum …
Selecting Lucerne Cultivars For Commercial Crop Processing And Fractionation In New South Wales, Australia,
2024
CSIRO
Selecting Lucerne Cultivars For Commercial Crop Processing And Fractionation In New South Wales, Australia, H T. Ostrowski-Meissner, F Falconer
IGC Proceedings (1977-2023)
The study was undertaken in the Lachlari River irrigation basin located in the central west region of New South Wales to obtain the fractionation characteristics of 23 varieties of lucerne (Medicago sativa) grown as pure crop stands on a commercial lucerne establishment and select for further study those varieties that showed potential for crop fractionation purposes. The results indicate that of the 23 varieties tested, 9 showed potential for commercial-scale fractionation. These were the Aurora, Trifecta, WL605, Hunterfield, GT58, Sequel, Validor, CUFlOI and Pioneer 5929 with the first three giving the highest yields of crop dry matter, crude …
Effect Of Seasonal Variation In The Fractionation Pattern Of Lucerne Selected For Commercial Crop Processing In Australia, H T. Ostrowski-Meissner, C J. Pearson, L M. Shields
IGC Proceedings (1977-2023)
The study was conducted on an irrigated lucerne (Medicago sativa) crop (cv. Aurora) harvested at the late vegetative stage of maturity for processing and fractionation during autumn, spring, early and late summer. The experiment was carried out using replicated commercial-sized irrigation bays with lucerne dry matter (DM) yields estimated to average some 19 t OM/ha/year. Despite irrigation, the lucerne harvested during the late summer season had the lowest nitrogen content at the time of harvest and yielded less lower crude protein lucerne extract as compared to those crops harvested during the spring and autumn seasons. The lower efficiency …
Direct Drilling Forage Maize Into Dairy Pastures In South-Eastern Australia,
2024
Institute for Sustainable Agriculture
Direct Drilling Forage Maize Into Dairy Pastures In South-Eastern Australia, K E. Pritchard
IGC Proceedings (1977-2023)
Forage maize (Zea mays) was planted directly into uncultivated dairy pastures after desiccation. A planter specially developed for this purpose, which used coulters, tynes and narrow rotary hoes to place fertiliser and seed precisely, achieved excellent crop establishment in dense redbrown earth soils. Yields were up to 22.7 t of dry matter/ha, similar to that of cultivated seedbeds with flood irrigation and 10% less than with furrow irrigation. Key agronomic requirements for success were a specialised planter, good surface drainage, adequate pre- and postplanting weed control and a requirement for early application of irrigation water and nitrogen fertiliser. …
Breeding To Reduce Susceptibility To Bloat In Dairy Cattle,
2024
AgResearch, NZ
Breeding To Reduce Susceptibility To Bloat In Dairy Cattle, C A. Morris, R J. Wilkins
IGC Proceedings (1977-2023)
An experiment with Friesian x Jersey cross cattle was established in 1972 at Ruakura, in order to select in 2 closed herds for high (HS) or low (LS) susceptibility to pasture bloat. By the 1990 calf crop, there was a difference in adjusted bloat score between herds of 0.94 units (1.93 genetic standard deviations). The repeatability and heritability of a single bloat score were 0.13+0.02, and 0.12+0.06, with a heritability of 0.52+0.22 for mean bloat score. Annual death rates from bloat have averaged 2.6% in the HS herd and 0.8% in the LS herd (0% in the LS herd for …
Mixed Herb Ley No Advantage Over Ryegrass-White Clover Pasture For Early Lamb Growth,
2024
AgResearch, NZ
Mixed Herb Ley No Advantage Over Ryegrass-White Clover Pasture For Early Lamb Growth, I Popay, W Stiefel
IGC Proceedings (1977-2023)
The performance of lambs at 2 stocking rates, on either ryegrasswhite clover (Lolium perenne- Trifolium repens) pasture or on a mixed herb ley, were compared under a system which precluded use of pesticides (including drenches) and highly soluble fertilisers. The mixed herb ley included 8 grasses, 5 legumes and 3 herbs: chicory (Cichorium lntybus), sheep's burnet (Sangulsorba minor ssp. muricata) and narrow-leaved plantain (Plantago lanceolata). In the first grazing cycle, there were no significant differences in lamb growth rates, nor in faecal egg counts, between the two pasture types, although in the …
Use Of Italian Ryegrass To Increase Feed Production From Dairy Pastures In Northern New Zealand,
2024
Dairying Research Corporation
Use Of Italian Ryegrass To Increase Feed Production From Dairy Pastures In Northern New Zealand, E R. Thom, R A. Prestidge
IGC Proceedings (1977-2023)
The effect on pasture production In late winter-early spring was examined by direct drilling Italian ryegrass (Lolilum multiflorum Lam. cv, Concord) into plots previously sprayed with glyphosate or undersowing into existing pasture in autumn 1989 and 1990. Nitrogen fertiliser (25 kg N/ha) was applied to half the area of each plot on 3 occasions during winter. Concord ryegrass was also direct drilled after spraying wilh glyphosate in late summer (February) and autumn (March) in a third experiment in 1991. All plots were rotationally grazed by cows. On average for late winter-early spring 1989 and 1990, direct-drilled and undersown plots …
Effect Of A Reduction In Concentrate Price On Feed Costs And Its Implication For Grass Silage In The Diet Of Lactating Dairy Cows,
2024
Moorepark Research Centre
Effect Of A Reduction In Concentrate Price On Feed Costs And Its Implication For Grass Silage In The Diet Of Lactating Dairy Cows, S Fitzgerald
IGC Proceedings (1977-2023)
The proposed reduction in the price of cereals (29%) under the EC price reform proposals for agricultural produce will have n large effect on feed costs and on the balance between grass silage and concentrates in the diet of lactating dairy cows while indoors. The effect of n reduction in the price of dairy concentrates with varying silage production costs on the daily feed costs for a 525 kg cow yielding 25 kg milk/day in early lactation, while losing 0.5 kg/day body weight, was calculated when given a mixed diet of grass silage and concentrates to provide an MB intake …
