Agricultural Science Commons^™

Modelling Nitrogen And Mineral Nutrient Uptake By A Grass Sward: Short Term Studies During The Sward Growth, J Salette, Lydie Huche, G Lemaire

IGC Proceedings (1977-2023)

In a previous work, the evolution of nitrogen and mineral content during the grass regrowth between two successive defoliations have been studied and modelled (Salette and Lemaire, 1981; Salette, 1982; Salette et al., 1982). This paper gives a generalization of the growth dilution and uptake model for nutrient minerals.

The Reaction Of Eragrostis Curvula To N And K Fertilization, N.F G. Rethman, C C. De Witt

IGC Proceedings (1977-2023)

Fertilization programmes for grass pastures in Southern Africa have placed emphasis on N and Pin the past. With the depletion of soil K, however, K fertilization is becoming increasingly important. Reliable response data for N and K fertilization is needed optimize fertilization level.

Efficacute De La Fertilization Minerale Des Prairies En Sol Alluvial, L Solimowski, R Lyszczarz, R Dembek

IGC Proceedings (1977-2023)

Le sol alluvial de la vallee basse de la Vistule offre des lieux naturels favorables a la culture des herbages (Cieslinski et Raszeja, 1983). On pratique assez souvent la seule fertilisation azotee, consideree comme la plus rentable. L'objectif de notre essai etait d'etudier !'influence des differents elements fertili­sants apportes pendant plusieurs annees sur la culture, !'evolu­tion de la composition botanique de la prairie, de la teneur en elements nutritifs de l'herbe et de la fertilite du sol.

Effects Of Fertilization And Liming On The Improvement Of Native Pastures, Maria E.V Lourenco, R.J. M. De Carvalho, Maria De L.A.P Da Silva

IGC Proceedings (1977-2023)

Native pastures in Portugal have relatively low productivity. The yield and botanical composition of such grasslands, where some legumes species are present, can be improved by fertilization with phosphorus application and/or also liming (Carter, 1983). The presence of legumes in pasture can also be improved by molybdenum application (Lattan et al., 1984). Significant increases of phosphorus concentration in plants (Garden et al., 1978) and on soil available phosphorus (Gregan et al., 1980) due to phosphorus application have also been reported.

The objectives of this study were to evaluate the potential of such treatments on the improvement of native pastures.

Influence Of Npk Fertilizer On Chrysopogon-Agrostis Swards, T Totev, V Vulkov

IGC Proceedings (1977-2023)

The Chrysopogon gryllus-Agrostis capillaris transitional association is commonly found in Bulgaria natural meadows. The aim of our investigation was, by applying different rates and proportions, to determine NPK fertilizer influence on the productivity, botanical composition and crude protein yield of the sward.

Derivation And Testing Of Nutrient Norms For White Clover, Marta J. Rodreiguez

IGC Proceedings (1977-2023)

Foliar analysis has been practiced widely to diagnose the nutrient status of crops in order to give fertilizer recommenda­tions. The changing nature of plant tissue mineral concentra­tions imposes limitations on the use of foliar analysis for diag­nostic purposes. In this way, sampling of particular plant parts at particular stages of development is required to assess the nutrient status of crop and forage plants. The Diagnosis and Recommendations Integrated System (DRIS) was developed by Beaufils (1973), based on a holistic experimental approach, as a means of coping with the problems derived of the dynamic nature of foliar composition. Three concepts are …

Influence De La Fertilization Sur La Repartition De La Biomasse Vegetale En Prairie Temporaire, R Lyszczarz

IGC Proceedings (1977-2023)

L'influence de la fertilisation minerale et organique sur le rendement et la composition botanique de la partie recoltable de la prairie est bien connue. Cependant nous n'en savons pas autant en ce qui concerne !'action de cette fertilisation sur Jes autres parties de la biomasse vegetale. Une etude approfondie de sa productivite, structure, composition chimique et reparti­tion permettrait d'evaluer son importance dans l'ecosysteme agricole (Hurto et al., 1980; Lutke, 1983).

Liming And Phosphate Fertilization On Forage Production, Mineral Composition And Nodulation On Pigeonpea (Cajanus Cajan (L.) Millsp.), V T. Paulino, N L. Costa, C.G S. Pedreira

IGC Proceedings (1977-2023)

For legume forage plant contribute effectively to grassland improvement, mainly through high herbage yields and fixation of atmospheric N, it is necessary to have a better knowledge of its nutritional requirements, since pigeonpea does not grow well on acidic soils with high levels of Al and poor in Ca, Mg and P. Ogunwale and Olaniyi (1978) reported a significant increase on forage production and P and Ca uptake for pigeonpea as a result of phosphate fertilization, while Abrufi.a et al., (1984) observed that lime improved growth, nodulation and P and Ca uptake, but with little effect on crude protein con­tent. …

Effect Of Rate And Placement Of Phosphorus On The Establishment Of Legume-Based Tropical Pastures On Oxisols, J M. Spain, R Gualdron, C Perdomo, P Avila

IGC Proceedings (1977-2023)

The phosphorus (P) requirements of perennial forage plants adapted to tropical savanna ecosystems are low compared to those of most annual crops or unadapted forage species (Andrew and Jones, 1985; CIAT, 1978). Perrenials are capable of accumulating P in the biomass over time and good pasture management favors micro-environmental conditions which can result in the recycling of P almost independent of the mineral soil (Spain and Salinas, 1985). It has been shown for crops that for maximum fertilizer efficiency at low rates, P should be concentrated near the seed to optimize fertility for seedlings, but there are few data for …

Use Of Cattle Slurry For Irrigated Temporary Grasslands, J Tomasik

IGC Proceedings (1977-2023)

Available literary sources deal almost exclusively with the slurry application for semi-natural grassland in diluted form, with varying rations of slurry and water (Rais and Kralovec, 1977, 1978 ; Schechtner, 1978 ; Schechtner, 1980; Sharda et al.,

1977 ; Tuney, 1980), The efficiency, i.e. production effect of slurry compared with industrial fertilizers varies in the quoted cases over the range of 50 to 111 %, depending on the most diversified natural and operating factors. We have therefore undertaken the task of identifying potential production capaci­ties of the selected set of monocultures of grasses in the appli­cation of increasing dosages of …

Influence Of Phosphorus Fertilization On Bahiagrass And Water Quality, G G. Payne, J E. Rechcigl

IGC Proceedings (1977-2023)

Increasing evidence suggests that P concentration is the pri­mary factor controlling the eutrophication of many surface waters (Taylor and Kilmer, 1980). Leaching and runoff losses of soluble P fertilizers applied to beef cattle pastures to increase forage production are believed to be a significant source of this P entering the water. Despite the fact that nearly one million hectares of bahiagrass are grown annually in Florida, relatively little is known about the nutrient requirements of bahiagrass for optimum forage production and quality. Currently, fertil­izer rates of up to 112 kg P2Os/ha are being recommended for bahiagrass pastures. There is mounting …

Potassium And Sulfur Fertilization Effects On Alfalfa Yields And Concentrations Of Minerals And Amino Acids, M Collins

IGC Proceedings (1977-2023)

Alfalfa (Medicago sativa L.) is an important perennial legume in ruminant feeding programs. Mechanical dewatering of alfalfa herbage yields a protein concentrate that contains 8.5 % of the DM and 29 % of the N from the original crop (Collins, 1985). Nonruminants would benefit from an increase in S amino acid concentrations of alfalfa since S amino acids limit utilization of leaf proteins (Byers, 1983). A greenhouse study was conducted to determine the effects ofK and S fertiliz­ation on the yield, composition and amino acid concentrations of alfalfa herbage.

Effects Of Phosphogypsum, Phsophorus And Lime On Andropogon Gayanus Kunth, V T. Paulino, E Malavolta

IGC Proceedings (1977-2023)

There 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 …

Red Clover Needs For Mobybdenum And Boron Soil Threshold Values Of Deficiency And Toxicity, H Gembrazewski

IGC Proceedings (1977-2023)

Red clover is a precious and promising fodder crop in Poland. Even on acid soils its yields are satisfying, if sufficient level of exchangeable Ca is present. Symbiotically fixed N covers N needs, but fixing effectiveness and rate of further changing of nitrogen compounds depends on optimal molybdenum supply. It is a component of such enzymes as nitrogenase and nitrate reductase, which make it necessary for Rhizobium as well as clover. However, Mo surplus is toxic for animals (the relation of Mo:Cu is of import­ance). As other leguminous plants, red clover needs much boron. Yield of 15 t of dry …

An Effective P Application Method For Dactylis Glomerata, M Hojito, A Nishimune, M Noshiro

IGC Proceedings (1977-2023)

There are two practical ways to apply phosphorus (P) fertil­izer on cutting type grasslands in Hokkaido, Japan. The first one is to apply P at a rate of about I 00 kg P2Os/ha in the spring (April) in one application. Some reasons for this method have been explained (Hayakawa et al., 1951). However, in some cases, it is more convenient for practical management to apply three equal amounts of P, at three different times during the year (April, June and August) the same as other fertilizers such as nitrogen or potassium. That is a second way. Grassland soil is acidified …

Distribution Of Phosphorus And Aluminum In Acidic Pasture Soils And Effects On Growth Of Subterranean Clover, M J. Mclaughlin, T R. James

IGC Proceedings (1977-2023)

In south-eastern Australia, pasture improvement and the use of superphosphate fertilizers have resulted in the gradual acidi­fication of many soils under subterranean clover pastures (Wil­liams, 1980). Despite high values of exchangeable and extract­able aluminium (and low pH) recorded in many soils, there are few reports of significant responses of clover growth to lime application in the field. In this study we examined the vertical distribution of CaCb-extractable aluminium (Al) and available phosphorus (Bray P) in pasture topsoils. We also simulated the conditions in the field sites by investigating in solution culture the response of subterranean clover to various concentrations of …

Relations Entre Facteur Hydrique, Drainage Er Evolution De La Flore Des Prairies En Lorraine, S Oberle, S Plantureux, R Bonischot, A Guckert

IGC Proceedings (1977-2023)

Une part non negligeable (plus de 50 %) des Surfaces Agri­coles lorraines est occupee par des prairies permanentes. Or, nombre de ces dernieres souffrent d'exces d'eau qui limitent gravement leur productivite. Le developpement recent d'opera­tion de drainage offre la possibilite de lever un facteur limitant et, ce faisant, d'augmenter significativement la qualite et la quantite du fourrage produit. Il convient toutefois de rappeler que Jes prairies permanentes sont constituees d'un ensemble d'especes vegetales en equilibre avec leur milieu ecologique. la perturbation de ce dernier, en !'occurrence la modification du regime hydrique, va entrainer la mise en place progressive d'un nouvel …

Influence Of Sulfur And Nitrogen On Bahiagrass, J E. Rechcigl, G G. Payne, R J. Stephenson

IGC Proceedings (1977-2023)

One of the most important forage crops grown in Florida is bahiagrass, with nearly 1 million ha grown annually. Bahia­grass is found on more acres than all other improved grass pastures combined. Average annual dry matter yields for bahiagrass range from 9 - 16 t/ha. Bahiagrass is adapted to most climatic conditions throughout the state and can be grown on upland well drained sands as well as poorly drained « flatwoods » soils. Until recently, little attention has been focused on the need for S fertilization for plant growth. This is understandable since, in the past fertilizers were contaminated with …

The Depletion Of Soil K As Affected By Fertilization Of Eragrostis Curvula Used For Hay Production, N.F G. Rethman, C C. De Witt

IGC Proceedings (1977-2023)

Eragrostis curvula is widely planted as a hay crop in the summer rainfall areas of South Africa. For many years the main yield determinants have been regarded as N and P. As a result of the depleting effect of crop removal low K status is becoming more common. The beneficial effect of K fertiliz­ation, in combination with N, has been illustrated by Miles et al. (1986) and Rethman and De Witt (1839). Information on the rate of build up and/or depletion of soil K under different fertilization regimes is, however, required to facilitate the plan­ning of fertilization strategies. The monitoring …

Studies On The Macropores Structure Of Grassland's Soil, K Sato, K Tokunaga

IGC Proceedings (1977-2023)

The purpose of this study is to examine the structure of macroporous soils which allows better aeration, water reten­tion and drainage. Previous investigations of macroporous soils have dealt with drainage (McIntyre and Sleeman, 1982), void forms (Tippkotter, 1983; Walker and Trudgill, 1983) and X-ray radiography (Rogaar, H. and R.A.H. Thiadens, 1975). Analyses of these studies have not proved sucessful to explain the effect of the soil structure as regards water retention and drainage. Therefore, the present study was designed to deter­mine the structure of macroporous soils by use of soft X-ray radiography and soil physical properties. Tokunaga et al.,(1984, 1986, …