Contribution A L’Etude Des Especies Spontanees Du Genre Scorpiurus L. En Algerie Ii. Durete Et Germination Des Graines Chez 29 Populations De S. Muricatus Subsp. Sulcatus (L.) Thell,
2025
Institut National Agronomique, Algerie
Contribution A L’Etude Des Especies Spontanees Du Genre Scorpiurus L. En Algerie Ii. Durete Et Germination Des Graines Chez 29 Populations De S. Muricatus Subsp. Sulcatus (L.) Thell, M M'Hammedi-Bouzina, A Abdelguerfi, R Berrekia
IGC Proceedings (1977-2023)
Les especes du genre Scorpiurus L., tres recherchees par le cheptel, peuvent jouer un role important dans !'amelioration des parcours et de la production des jacheres. Outre leur inten��t fourrager, elles concourent au maintien de la fertilite des sols grace a leurs caracteristiques agronomiques (fixation d'azote, systeme racinaire puissant, port etale ... ). Mais !'utilisation de ces especes spontanees de legumineuses reste conditionnee par !'estimation de la proportion de graines dures et Jes moyens a mettre en ceuvre pour surmonter cet obstacle a la germination. Ainsi, et suite aux travaux de Bensalem et al. (1988) sur le genre Scorpiurus et …
Grass Adaptation In Cuba. I. Characterization Of The Areas Dedicated To Livestock Production,
2025
Ministry of Agriculture, Cuba
Grass Adaptation In Cuba. I. Characterization Of The Areas Dedicated To Livestock Production, J J. Paretas
IGC Proceedings (1977-2023)
The present study is aimed to point out various aspects allowing to locate and learn the soil, climate, social and economic conditions as well as the production characteristics of pastures and forages and their utilization for milk and beef production under Cuban conditions.
Perennial Legumes And Grass-Legume Associations Adapted To Poorly Drained Savannas In Tropical South America,
2025
CIAT/EMBRAPA/IICA
Perennial Legumes And Grass-Legume Associations Adapted To Poorly Drained Savannas In Tropical South America, B Grof, D Thomas, R P. De Andrade, J.L F. Zoby, M A. De Souza
IGC Proceedings (1977-2023)
Seasonally flooded areas and swamp grasslands constitute a significant percentage ot the savannas and represent an important source of supplementary forage during the dry season. Approximately 21 % (170 million ha) of the central lowlands of tropical South America is poorly drained ; 82 % of these lands (139 million ha) is covered with forest and the remaining 31 million ha by native savannas (Cochrane et al.,1985). The poorly drained savanna lands have been used successfully since colonial times for extensive cattle production. Significant areas are found in the Brazilian Pantanal, in Brazil's southwest Amazonia, the Casanare plains of northeast …
The Effect Of Nitrogen And Clover Proportions On Yield Of Red Clover-Grass Mixtures,
2025
Swedish University of Agricultural Sciences
The Effect Of Nitrogen And Clover Proportions On Yield Of Red Clover-Grass Mixtures, B E. Frankow-Lindberg
IGC Proceedings (1977-2023)
Red clover is the most important forage legume in Swedish ley farming (c. 500 tonnes of seed certified in 1986/87). It is traditionnally sown with a mixture of grasses, typically timothy and meadow fescue. Recommendations for maximum DM yields, obtained from extensive series of experiments, given no fertilizer nitrogen (Bengtsson, 1964; Arnemo and Steen, 1972) are 4-6 kg/ha red clover seeds ( of a diploid cul ti var) in a mixture of totally 20-24 kg/ha seeds sown. Red clover content in the established sward declines with time from c. 60 % in the firstyear crop to c. 25 % in …
Some Changes In Biological Soil Characteristics Of Grassland Ecosystem Under Different Management Intensity,
2025
Grassland Institute of Soil Fertility Research Centre
Some Changes In Biological Soil Characteristics Of Grassland Ecosystem Under Different Management Intensity, L Ondrasek
IGC Proceedings (1977-2023)
The papers which are in our country engaged in problems of soil biological processes under treated seminatural grassland are orientated mainly on the determination of quantitative and qualitative extents of changes originated especially under influence of application of increasing level of nitrogen fertilizers in relation to possible negative phenomenons in environments (Kopcanova et al., 1985, Tesafova and Gordienko, 1988). Our paper deals also with those problems. Its aim is to give a short information about some important changes in biological soil properties under long time differently managed grassland.
Dairying In New Zealand,
2025
Dairying Research Corporation, NZ
Dairying In New Zealand, A M. Bryant
IGC Proceedings (1977-2023)
Many of you are visitors to this country. This afternoon you saw something of an industry quite different from yours back home. The objective of my talk is to help you identify what these differences are and why they exist. By the end of the day you should have a picture of how one industry • the dairy industry • has integrated a whole range of systems into a successful whole.
Regrowth Sites Of Sulla (Hedysarum Coronarium L.) After Defoliation,
2025
Massey University
Regrowth Sites Of Sulla (Hedysarum Coronarium L.) After Defoliation, H Krishna, P D. Kemp
IGC Proceedings (1977-2023)
Sulla is a semi-perennial herbaceous forage legume which has rarely been used for grazing. Field studies were undertaken to determine the relative importance of regrowth sites on sulla so that guidelines for grazing management could be refined. Regrowth was predominantly from the crown and most stems remaining after grazing subsequently died. It is concluded that grazing management should be severe and infrequent but, because regrowth is from the crown, treading damage needs to be avoided.
Science And Information For Our Grasslands,
2025
CIAT
Science And Information For Our Grasslands, G A. Nores, R R. Vera
IGC Proceedings (1977-2023)
This paper favours a view of grasslands, and agricultural research in general, that extends well beyond the limits of the scien1ific cummunity and promotes the active involvement of scientists in current societal debates from a ��cientific perspective. It is argued that in developed counuies environmental concerns rather than production growth will tend to dominnte future social debate, In developing countries there is a need to balnnce agricultural growth with responsible management of natural resources. Needs for new technology go beyond improving biophysical efficiency, and involve economic and social efficiency objectives. The relevance of grassland research is ��ssessed in terms of …
Genetic Engineering For Pastures,
2025
CSIRO
Genetic Engineering For Pastures, W J. Peacock
IGC Proceedings (1977-2023)
The flrst genetically engineered food products frolll hotticultural production systems are now enlering the Market and field trials of genetically engineered crop species are well advanced. We can expect that a range of crop cultivars, in which genetic engineering is n component of the breeding process, will soon go into broad ncre agriculture. Pasture species are nut far behind. Gene transfer systems are in place for a number of temperate and tropical pasture legumes and even for a few species of more dlrficult grasses. Genetic transfer systems are In place for a numoec of temperate and tropical pastvce legumes and …
Nitrogen Fixation And Transfer To Associated Grasses By White Clover Cultivars Under Dairy Cow Grazing,
2025
Ruakura Agricultural Centre
Nitrogen Fixation And Transfer To Associated Grasses By White Clover Cultivars Under Dairy Cow Grazing, S F. Ledgard
IGC Proceedings (1977-2023)
New Zealand pastures obtain most of their nitrogen (N) from fixation of atmospheric N2 by white clover (Trifolium repens L.). Grasslands Huia has been the predominant cultivar used, but in recent years a number of new cultivars have become available. Studies under mowing and sheep grazing have shown that the large-leaved cultivars are the most productive (van den Bosh et al., 1986; Frame and Boyd, 1987). These cultivars have not been evaluated under dairy cow grazing. This paper describes a 2 year field experiment examining white clover cultivars under dairy cow grazing for production, N2 fixation and transfer of …
N-15 Study Of Nitrogen Uptake By Tall Fescue Throughout A Spring Growth,
2025
INRA
N-15 Study Of Nitrogen Uptake By Tall Fescue Throughout A Spring Growth, J Salette, Marie-Laure Decau, Francoise Vertes
IGC Proceedings (1977-2023)
In previous works, nitrogen uptake by a grass sward during regrowth has been studied and modelled (Salette and Lemaire, 1981 ; Lemaire and Salette, 1984). In this study, the use of N- 15 labelled fertilizer allows differentiation of two nitrogen sources for the plant nutrition : soil and fertilizer.
Spring Nitrogen Uptake In Grass Swards In Relation To N Fertilizer Rates And Variation Between Years,
2025
INRA
Spring Nitrogen Uptake In Grass Swards In Relation To N Fertilizer Rates And Variation Between Years, J Salette, Marie-Laure Decau, G Lemaire
IGC Proceedings (1977-2023)
No abstract provided.
Ajustement De L’Azote Recolatable Dan Les Fourrages A L’Offre Minerale Dans Les Prairies Permanentes,
2025
INRA
Ajustement De L’Azote Recolatable Dan Les Fourrages A L’Offre Minerale Dans Les Prairies Permanentes, P Loiseau, P Monteilhet
IGC Proceedings (1977-2023)
Une-serie de recherches-a-ete entreprise-dans-Je-but d\��value la reponse a l'azote des prairies dans l'etage collineen subatlantique. La contribution du sol a l'azote recoltable dans !es fourrages et Jes coefficients d'utilisation des apports mineraux sont etudies en fonction de differents parametres. Le but pratique est d'ameliorer le conseil de fumure azotee. Mais Jes recherches incluent aussi une connaissance plus approfondie du comportement de l'azote dans Jes sols sous prairies. Une des recherches a ete appliques aux prairies permanentes de fauche en zone de piemont.
Etude Du Stock D’Azote Mineralizable Dans Les Milieux A Teline Linifolia De La Suberaie En Mamora (Maroc).,
2025
Ecole Nationale Forestiere d'Ingenieurs
Etude Du Stock D’Azote Mineralizable Dans Les Milieux A Teline Linifolia De La Suberaie En Mamora (Maroc)., M Qarro, A Harcharass
IGC Proceedings (1977-2023)
Les facies de Teline linifolia (genet) couvrent actuellement de vastes etendues en foret de Mamora (63% de chene-liege, 24% d'eucalyptus, 5% de Coniferes et 8% de vides et dayas) avec des recouvrements tres eleves. Le developpement de cet arbuste est favorise par !'interdiction de la chevre qui regularise la densite du sous-bois (Qarro, 1986). Notre etude, engagee dans ces milieux, vise a etudier le role ecopedologique de cette legumineuse (Teline linifolia) sur Jes sols sablonneux pauvres en elements mineraux (l'azote particulierement) et plus particulierement Jes relations entre le recouvrement de Teline et le stock d'azote mineralisable. II convient de tester …
Seasonal Variations In Soil Mineral Nitrogen And In The Response Of Grassland To Nitrogen Fertilization,
2025
Institute for Soil Fertility
Seasonal Variations In Soil Mineral Nitrogen And In The Response Of Grassland To Nitrogen Fertilization, O Oenema, J Postmus, W H. Prins, J J. Neeteson
IGC Proceedings (1977-2023)
Grassland is intensively used in the Netherlands. According to the fertilizer recommendation, the optimum N supply for such grassland is 250 kg ha-1 yr-1 for well-drained peat soils and 400 kg ha-1 yr-1 for all other soils. Environmental problems, associated with N losses from intensively used grassland, necessitate a refinement of the general recommendations. This, in turn, requires understanding of the dynamics of soil mineral nitrogen. This paper reports on (1) seasonal dynamics of soil mineral N and (2) seasonal variations in the response of cut swards to N. Results of grazed swards will be dealt with elsewhere (Oenema et …
Ammonia Volatilisation And Loss From Grassland Systems,
2025
AFRC
Ammonia Volatilisation And Loss From Grassland Systems, S C. Jarvis, B F. Pain, D J. Hatch, R B. Thompson
IGC Proceedings (1977-2023)
There is considerable interest in monitoring flows of nitrogen (N) through various parts of grassland systems. Until recent developments in methodology it had been particularly difficult to assess the contribution of NH3 volatilisation to N cycling. Emission rates for NH3 over Europe are thought to have increased by 50 % over the past 30-40 years and to arise largely from livestock excreta. This occurs after the hydrolysis of excreted urea and, with cattle, takes place directly from grazed swards, animal houses (during overwintering) and stored or applied slurry. As well as the economic losses, NH3 fluxes have important environmental consequences …
The Effects Of Fertilizer/Urine Interactions On Nh3 -N Losses From Grassland Soils,
2025
AFRC
The Effects Of Fertilizer/Urine Interactions On Nh3 -N Losses From Grassland Soils, R D. Meyer, S C. Jarvis
IGC Proceedings (1977-2023)
Recent studies (Black et al., 1984) have indicated that the volatilisation of ammonia (NH3) from urea granules broadcast on to pastures at application rates of 50-100 kgN/ha often exceeds 20 % of the N applied. The extent of this loss becomes an important consideration when manipulating management systems to maximise N efficiency and minimise losses to the environment. This will become especially important as the use of urea fertiliser increases because of relative cheapness and as technological advances in production and in farm handling are made (Gould et al., 1986). The factors influencing the volatilisation of urea in simple systems …
Nitrogen Losses From Cattle Dung,
2025
Miyazaki University
Nitrogen Losses From Cattle Dung, Y Sugimoto, P Roger Ball
IGC Proceedings (1977-2023)
Nitrogen (N) recylcing through animal excreta has long been considered beneficial to soil fertility in pasture. However, it was revealed recently that substantial N loss occurred via urine patches in intensively managed grass-clover pastures in New Zealand (Ball et al, 1979 and 1981; Ball and Ryden, 1984). Nitrogen flow through dung patches is another main process in N recycling, as one-third to a half ot the N excreted by cattle and sheep is voided in dung (Whitehead, 1970; Sugimoto et al, 1987). The objective of this research was to determine the nitrogen losses from cattle dung in a ryegrass-white clover …
Balances Of Forms Of Mineral N In Grazed Grassland Soils Impact Of N Losses,
2025
AFRC
Balances Of Forms Of Mineral N In Grazed Grassland Soils Impact Of N Losses, S C. Jarvis, J H. Macduff, J R. Williams, D J. Hatch
IGC Proceedings (1977-2023)
Improving the efficiency of nitrogen (N) utilization and reducing losses requires an understanding of N transformations in soils. A key process is nitrification, which qualitatively and quantitatively determines the fate of NH4 +. This is especially important in grazed grassland where returns of urinary N provide a large supply of NH4 +. After grazing has finished there may be accumulations of N which, if nitrified, will be lost by leaching (freely drained soils) or denitrification (poorly drained soils) in temperate regions. Where nitrification is restricted, opportunity for loss is correspondingly less. Field measurement of nitrification is difficult because of interactions …
Modelling The Nitrogen Cycle Of Intensively Managed Grasslands To Estimate Nitrogen Losses,
2025
CABO
Modelling The Nitrogen Cycle Of Intensively Managed Grasslands To Estimate Nitrogen Losses, G.W J. Van De Ven
IGC Proceedings (1977-2023)
No abstract provided.
