Azote Et Equilibre De L’Association Ray-Grass Anglias-Trefle Blanc,
2025
INRA
Azote Et Equilibre De L’Association Ray-Grass Anglias-Trefle Blanc, J C. Simon
IGC Proceedings (1977-2023)
Bon nombre d'eleveurs s'interrogent sur l'interet des apports d'azote sur les associations ray-grass anglais - trefle blanc, en particulier sur la premiere pousse de printemps. Ces apports conduisent generalement a un desequilibre de !'association en faveur du ray-grass et compromettent de ce fait la perennite du melange. Apres avoir rappele brievement par quelques resultats experimentaux les principales incidences de l'azote sur le niveau de production et sur la composition de la culture mixte, nous analyserons les effets de l'azote sur l'equilibre de !'association a la lumiere des donnees recentes sur la morphogenese des deux plantes.
The Effects Of Coconut Palms On Pasture Understory,
2025
University of Reading
The Effects Of Coconut Palms On Pasture Understory, R W. Snaydon, D.N S. Fernando, R Sangakkara
IGC Proceedings (1977-2023)
Pastures are extensively grown under coconut palms, and mainly grazed by cattle (Plucknett, 1979). The main advantages of this form of mixed cropping are : (a) diversification of products, (b) additional income, (c) feed for draft animals, (d) weed control, and (e) more rapid nutrient cycling. Surprisingly little information is available on the effects of pastures and coconut palms on each other (Plucknett, 1979) ; even less is known about the mechanisms of competition between them. This study was designed to study the effects of coconut palms on pasture. A trenching technique was used to investigate the effects of below-ground …
Compatibility Of Birdsfoot Trefoil With Tall Fescue Selected For High And Low Leaf Area Expansion Rate,
2025
USDA, Agricultural Research Service
Compatibility Of Birdsfoot Trefoil With Tall Fescue Selected For High And Low Leaf Area Expansion Rate, C J. Nelson, K M. Hasson, D A. Sleper, J R. Forwood
IGC Proceedings (1977-2023)
Tall fescue (Festuca arundinacea Schreb.) populations were selected for slow and rapid leaf area expansion rate (Nelson and Sleper, 1983). Daily leaf elongation rate (LER) in the field was increased by 0.30 mm and decreased by 0.53 mm per generation (Nelson et al., 1985), but single-leaf photosynthesis was not affected. Populations selected for high LER had longer and wider leaf blades (Nelson and Sleper, 1983), and lower tiller density, higher weight per tiller, and higher forage yield in vegetative swards (Nelson et al., 1985) than those selected for slow LER. Zarrough et al. (1983) suggested that tall fescue could …
Determination Of Predictive Zones For The Evaluation Of Herbage Grasses In Cuba,
2025
Estacion Experimental de Pastos y Forrajes
Determination Of Predictive Zones For The Evaluation Of Herbage Grasses In Cuba, J Gerardo, Hilda Machado, Verena Torres
IGC Proceedings (1977-2023)
Regional 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.
Varieties Evaluation Of Lucerne (Medicago Sativa) With Different Winter Dormancy Class,
2025
EEA
Varieties Evaluation Of Lucerne (Medicago Sativa) With Different Winter Dormancy Class, O A. Bruno, R J. Leon, L A. Romero, O R. Quaino
IGC Proceedings (1977-2023)
Lucerne, pure or as a component of mixtures, is the forage more used in many regions of Argentine. In the central part of Santa Fe province it is the basis of feeding in the milk production systems. The diffusion of this species was done by mean of populations, that at the beginning of this century produced forage of high yield, quality and good persistency. Later, the area ofland cultivated fluctuated, characterized by periods of diminishing and recovery. From 1969 the appearance of Pea aphid (Acyrthosiphum pisum) gave rise to a critical situation. The solution to this problem was …
L’Effet Du Climat Sur La Production Des Herbages,
2025
Universite d'Agronomie
L’Effet Du Climat Sur La Production Des Herbages, I Vinczeffy
IGC Proceedings (1977-2023)
Dans les regions arides on peut optimiser la production des herbages par une technologie adaptee au climat, meme dans des sols pauvres. Le climat de la Hongrie est en grande partie sec, Jes sols des herbages sont defavorables, la vegetation est degradee et l'effet des engrais est modere. Le rapport entre le climat et la production est presente par Jes donnees du ne traitement d'une experience de 9 ans.
Effects Of Temperature And Photoperiod On The Extension Growth Of Six Temperate Grasses,
2025
University of Alberta
Effects Of Temperature And Photoperiod On The Extension Growth Of Six Temperate Grasses, G.A Van Esbroeck, Jane R. King, V S. Baron
IGC Proceedings (1977-2023)
In western Canada late season pasture yields vary considerably among species. During August and early September yields of Bromus riparius and Dactylis glomerata are double that of the more commonly grown Bromus inermis (Knowles and Sonmore, 1985). The importance of leaf area to crop growth rate pnor to canopy closure is well documented (Rhodes, 1973). Two components of leaf area are the final size of leaves and the rate of leaf appearance, with final size of leaves largely dependant on the rate of extension and duration of extension (Edwards, 1967). Since the maturity of a leaf is closely associated with …
C-4 Grass With Legumes: An Energy Efficient Biomass System,
2025
University of Illinois
C-4 Grass With Legumes: An Energy Efficient Biomass System, C J. Kaiser
IGC Proceedings (1977-2023)
Converting solar energy into biomass is theoretically most energy efficient when species of a high photosynthetic capacity are grown and nitrogen is furnished via symbiotic fixation. Perennial warm season grasses with the C-4 photosynthetic pathway outyield perennial cool season grasses that possess less efficient C-3 pathways. Growing a productive perennial warm season grass in sequence with a winter annual legume should increase yearly capture of solar energy per unit area. The different seasonal growth patterns of the winter legume and the C-4 grass should result in less inter-species competition than occurs in traditional cool season grass-legume combinations. As a result, …
Preliminary Rate Of Growth Curves For Legume Based Improved Pastures In The Mid-Altitude Region Of Yunnan Province Of Southern China, J R. Bruce-Smith, Yang Guo-Rong, Huang Bi-Zhi, Li Ji-Xin
IGC Proceedings (1977-2023)
Yunnan Province in south west China is very mountainous and has several major climatic/ecological zones ranging from tropical to alpine but all are dominated by the south Asian monsoonal rainy season. Extensive tracts of hilly depleted range lands occur in the mid-altitude zone (1800-2500 m) that are potentially suitable for developing to improved legume based pastures. Results of investigations as to suitable species and appropriate fertilizers for this purpose have been discussed previously (Mathison et al., 1985 and Wang et al., 1985). The Project has succesfully established model farms at several places throughout the Province and these carry reasonably productive …
Effects Of Low Temperature On Germination Of Herbage Species Used In New Zealand,
2025
Massey University
Effects Of Low Temperature On Germination Of Herbage Species Used In New Zealand, J.F L. Charlton, J G. Hampton
IGC Proceedings (1977-2023)
In recent years, New Zealand's grassland industry has been diversified by the farming of different livestock types, and by using a wider range of pasture species. Some of the latter have establishment and growth patterns very different from the herbage species perennial ryegrass (Lolium perenne L.) and white clover (Trifolium repens L.), used traditionally by New Zealand farmers. Successful seedling establishment is critical for subsequent successful performance in a pasture. Quality of herbage seed is judged by thousand seed weight, analytical purity, freedom from undesirable weed seed contamination, and high germination capacity. Internationally accepted procedures are used to …
Spanish Subclover Ecotypes: Evaluation Under Grazing,
2025
Servicio Investigacion Agraria, Spain
Spanish Subclover Ecotypes: Evaluation Under Grazing, L Olea, C Bueno, J Paredes, P Verdasco
IGC Proceedings (1977-2023)
The introduction of australian subclover varieties in the mediterranean environments of Europe has had irregular results (Olea et al., 1985). For this reason, important projects in selection and genetic improvement of subclover varieties adapted to these environments are carried out in Spain, Portugal and Sardinia. The selection program used at Badajoz (Spain) has originated ecotypes which have been described by Gomez Pitera (1985) and Gonzalez et al. (1986). These ecotypes have short cycles, high level of hardseedness, high seed production and long flowering period. The final stage in the selection of pasture plants must include the evaluation under grazing. Subclover …
Behaviours Of Annual And Perennial Grass Species In The Same Genus,
2025
Chiba University
Behaviours Of Annual And Perennial Grass Species In The Same Genus, Y Takasaki, A Isoda, H Nojima, H Oizumi
IGC Proceedings (1977-2023)
A genus including crop species usually has annual and perennial species. Although life history is genetically controlled, it is not fully investigated how it is expressed (Nooden, 1980; Woolhouse, 1982). We examined the behaviours of annuals and perennials in the genera Avena, Hordeum, Lolium and Oryza.
Vegetative Growth And Development Of Norwegian Poa Pratensis L. Ecotypes As Influenced By Temperature And Photoperiod,
2025
Landvik Research Station, Norway
Vegetative Growth And Development Of Norwegian Poa Pratensis L. Ecotypes As Influenced By Temperature And Photoperiod, T S. Aamlid
IGC Proceedings (1977-2023)
Temperature and photoperiod are the main environmental factors affecting flower induction in Poa pratensis (Heide, 1980). As all tillers have a juvenile stage, seed yield depends on both number and size of tillers at the end of the previous growth season. Furthermore, most of the seeds are produced on aerial shoots from the rhizome system (Borg, 1974). Thus, the aim of the experiment was to examine the influence of temperature and photoperiod on growth and development of various ecotypes.
Herbicide Utilization For Regulation Of Botanical Composition Of Grass Swards,
2025
Grassland Institute of Soil Fertility Research Centre
Herbicide Utilization For Regulation Of Botanical Composition Of Grass Swards, A Lackovic
IGC Proceedings (1977-2023)
In Czechoslovak conditions especially in Slovakia the botanical composition of grass swards is for different reasons getting worse and this means the decrease of forage value. As all those swards cannot be improved by complete renovation or by direct strip drilling of productive species into the sward, other possibilities are looked for. One for those is the utilization of herbicides combined with adequate fertilization. Retardation or control of unfavourable species destroy the existing competition which causes the different species succession in the sward. Our aim was to make a positive succession of species in the sward by herbicides utilization and …
Allelopathic Influence Of Certain Pasture Weeds,
2025
University of Georgia
Allelopathic Influence Of Certain Pasture Weeds, A E. Smith
IGC Proceedings (1977-2023)
Allelopathy, the direct or indirect effect of one plant on another through the production of chemical compounds that escape into the environment (Rice, 1974) occurs widely in natural plant communities (Gressel and Holm, 1964), and is postulated to be one mechanism by which weeds interfere with crop growth (Gressel and Holm, 1964; Bell and Koeppe, 1962; Muller, 1966). Probably the most significant consequence of allelopathy is the alteration of population densities that affect vegetation patterns in plant communities. The actual and potential roles of allelopathy in agriculture have been extensively reviewed (Putman and Duke, 1978; Rice, 1974; Rice, 1979). Generally, …
Economics Of Controlling Weeds Of Permanent Pasture,
2025
MAFTech
Economics Of Controlling Weeds Of Permanent Pasture, I Popay, N Barlow
IGC Proceedings (1977-2023)
In general, inedible weeds of permanent pasture reduce pasture dry matter available to stock in direct proportion to their cover (Doyle et al., 1984). Translating the effects of weeds on pasture to reductions in animal production is difficult because (i) pasture value can range from zero to the cost of purchased feed (ii) weed effects and pasture value can vary seasonally and interact and (iii) reductions in pasture availability at one time affect later growth (Auld et al., 1987). There have been few direct measurements of effects of pasture weeds on animal productivity, because of the co.sts involved. However, simulation …
Weed Development In Tropical Sown Pastures,
2025
University of the West of Scotland
Weed Development In Tropical Sown Pastures, G.E D. Tiley
IGC Proceedings (1977-2023)
The use of artificially sown pastures is relatively recent in the tropics. Grasses and legumes have been evaluated for their value to livestock as well as the more traditional use of resting arable land after cropping. Using the criteria of ease of establishment, production under grazing and botanical stability, a number of species and mixtures were recommended for the humid areas of Uganda (Horrell and Tiley, 1970). Control of weed growth during early establishment and suppression of unsown species subsequently were found to be vital for the success of these tropical ley pastures. The results of monitoring weed development in …
Insect Pests As A Limiting Factor In Green Fodder Production In Lucerne, Their Control And Residual Persistence Of Insecticides,
2025
Indian Grassland and Fodder Research Institute
Insect Pests As A Limiting Factor In Green Fodder Production In Lucerne, Their Control And Residual Persistence Of Insecticides, V J. Shivankar
IGC Proceedings (1977-2023)
The green fodder production in lucerne suffers serious loss of about 38 % caused by the insect pests like Empoasca sp., Therioaphis maculata Buck, Aphis craccivora Koch and Hypera variabilis Herbst. under the tropical agroclimatic zone of Bundelkhand-India (Shri Ram and Gupta, 1976). Of these H. variabilis is most serious with regular occurrence and worldwide distribution. No work has been reported on the control aspect of these pests in India, except a few on insecticidal evaluation (Shri Ram and Gupta, 1975) and the economic injury level of lucerne weevil (Gupta et al., 1982). Need of the studies on the chemical …
Sitona Hispidulus Larvaw As A Stress On Alfalfa Production,
2025
USDA, Agricultural Research Service
Sitona Hispidulus Larvaw As A Stress On Alfalfa Production, A A. Hower, K T. Leath
IGC Proceedings (1977-2023)
Sitona weevils are pests of various legumes throughout the world. In the United States, the clover root curculio, S. hispidulus (F.) is the major species associated with lucerne (alfalfa) Medicago sativa L. This insect has until recently remained obscure as a pest of this major forage crop. However, a recent trend in premature decline of alfalfa has prompted further investigation of this insect/legume interaction. Godfrey and Yeargan (1987) and Hill et al. (1969) indicated that S. hispidulus reduced alfalfa production. While adults S. hispidulus feeding on the foliage is of little consequence, it is the association of larvae with …
Resistance To Plant Parasitic Nematodes In Ryegrasses And White Clover,
2025
Welsh Plant Breeding Station
Resistance To Plant Parasitic Nematodes In Ryegrasses And White Clover, R Cook, K A. Mizen
IGC Proceedings (1977-2023)
Field and glasshouse experiments indicate that several nematodes damage ryegrasses and white clover (Cook and York, 1985). Populations of these nematodes under grassland are often at potentially damaging densities. Several nematode species of long-term grassland have co-evolved host relationships in which host resistance is likely to have been selected. This is of direct practical relevance to the control of three nematodes, widespread in England and Wales: the root-knot nematode (Meloidogyne naasi) on ryegrasses; and the stem nematode (Ditylenchus dipsaci) and cyst nematode (Heterodera trifolii) on white clover. Our objectives have been, first, to identify resistant …
