Lowering Cocksfoot Yields Caused By Manganese Toxicity And Molybdenum Deficiency Caused By Acidifying Effect Of Ammonium Nitrate Application, H Gembrazewski, Urszula Sienkiewicz
IGC Proceedings (1977-2023)
In the case of cocksfoot (Dactylis glomerata L.) cultivation in monoculture or its domination as a result of high N level further regrowth yields decrease is often observed. This situation also takes place on fertile soils and during years with good precipitation amounts. Similarly in pot experiments with optimal water and nutrients-N.P.K.-supply, this phenomenon also takes place. According to many research works, N application systematically acidifies the treated soil. In Poland 60 % of soils are acid ones (pHKcl < 5,6). Sandy soils dominating in Poland are poor organic matter and they possess low buffering capacity. They are not resistant to acidifying effect of nitrogen fertilization which, besides biological oldering of plants, can be the reason of yields lowering in further harvests. Lowering of soil reaction strongly effects micronutrients availability to plants to which its insufficiency or surplus is harmful. The problem of Mn toxicity and Mo insufficiency on acid soils is often discussed. The aim of the present research is to investigate the influence of increasing rates of commonly used N source - ammonium nitrate - on the yield and chemical composition of cocksfoot.
Rendement Des Prairies Dans Les Marais De L'Ouest De La France. Diagnostic Des Insuffisances Minerales,
2025
INRA-DRSAD
Rendement Des Prairies Dans Les Marais De L'Ouest De La France. Diagnostic Des Insuffisances Minerales, Y Pons, E Lafon
IGC Proceedings (1977-2023)
Situes sur la cote atlantique entre la Vilaine au Nord et la Gironde au Sud, !es Marais de l'Ouest s'etendent sur 250 000 ha environ. Ils resultent du comblement d'un golfe marin par des alluvions fluviomarines argileuses. La prairie est la production obligatoire lorsque !es contraintes hydrauliques ne sont pas maitrisables ou lorsque le cout d'amenagement est prohibitif. C'est le cas d'une part des marais "mouilles" qui sont soumis aux crues des rivieres (sols tourbeux et argileux) et d'autre part des marais desseches lorsque !es sols sont sodiques et done tres instables. L'objectif de l'etude est d'expliquer !es ecarts de …
A Time For Change- Issues Arising From The Xvii International Grassland Congress Developed World Viewpoint,
2025
Manaaki Whenua Landcare Research
A Time For Change- Issues Arising From The Xvii International Grassland Congress Developed World Viewpoint, Barney Foran
IGC Proceedings (1977-2023)
A number of major issues raised at the conference, if they are accepted by farmers and grassland scientists, will mean a major realignment of both the philosophy and practice of grassland science. The first of these is future world trade flows and a bleak prognosis for traded livestock products. Jf the developed world accepts that developing nations have to trade in order to develop, and trade in commodities where they have a cost advantage, this suggests that bulk production of livestock commodities will decline ln total. Thus grassland exports will have to concentrate on high value niche markets. This poses …
Congress Outlook From The Developing Countries' Perspective,
2025
United Nations University
Congress Outlook From The Developing Countries' Perspective, Bede N. Okigbo
IGC Proceedings (1977-2023)
In this XVII International Grassland Congress, which is now successfully drawing to a close, we are all very grateful for the opportunity to participate and enjoy the hospitality of our New Zealand and Australian hosts. Above everything else, we have benefited much more from attending than we have individually contributed to its success in various ways.
Water Balance And Soil Fertility Characteristics Of Brigalow (Acacia Harpophylla) Lands Before And After Forest Clearing,
2025
Queensland Department of Primary Industries
Water Balance And Soil Fertility Characteristics Of Brigalow (Acacia Harpophylla) Lands Before And After Forest Clearing, Paul A. Lawrence, B A. Cowie, D Yule, P J. Thorburn
IGC Proceedings (1977-2023)
A multidisciplinary study was undertaken to investigate the changes in catchment runoff, groundwater recharge and soil fertility after the complete removal of brigalow (Acacia harpophylla) forest for buffet grass pasture. Clearing brlgalow for pasture increased runoff amount by 21 mm/year; however, runoff represented a·· small (11-14%) component of the annual water balance. An increase in groundwater recharge immediately after clearing was not sustained once the pasture was established. Clearing did not alter the annual water balance, evapotranspiration taking 90% of annual rainfall, Clearing and burning• caused a flush of plant available N, P and K but this was …
Successional Dynamics Of An Acacia Savanna In Southern Africa,
2025
UN/FRD
Successional Dynamics Of An Acacia Savanna In Southern Africa, C. Richard Hurt, Richard I. Yeaton
IGC Proceedings (1977-2023)
Acacia-dominated savannas iii southern Africa are ·maintained by disturbance. Wheri ihese ecosystems are managed as pastoral systems, the disturbance regime is altered, • arid the· successional sequence proceeds to broad-leafed woodland. We examined changes in woody species composition over a soil catena, and used sliccessional stages within an acacia-dominated community to develop a Markov model of the dynamics of the system. We used this model to simulate 2 management scenarios and to make predictions · of associated community changes over time.
Deforestation In Pakistan,
2025
WWF - Pakistan
Deforestation In Pakistan, Inayat U. Chaudhry
IGC Proceedings (1977-2023)
Pakistan's economy is agricultural and pastoral. From 1150 to 1991 its forest cover declined from an estimated 28 million ha to 4,6 million ha and population increased from 1.2 to 112 million. rn addition to. increasing population, government irrigation projects for colonisation, in road of agriculture into forestry and construction of barrages over rivers caused deforestation. This has increased soil erosion, siltation of dams and the gap in production and demand of wood: biodiversity has been adversely affected and mangrove forests have degraded. Forestation has been carried out over 220 000 ha since 1947. A network of easily accessible nurseries, …
Animal Production From Tropical Semi-Arid Savannah Woodland In Subcoastal Queensland, Australia,
2025
QDPI
Animal Production From Tropical Semi-Arid Savannah Woodland In Subcoastal Queensland, Australia, H G. Bishop, H J. Chamberlain, R M. Dodt, T B. Hilder, G A. Lambert, E R. Anderson
IGC Proceedings (1977-2023)
Annual live-weight gain of steers grazing on virgin tropical semiarid poplar box (Eucalyptus populnea) savannah woodland in subcoastal central Queensland fluctuated between 59 kg/head and 200 kg/head over a 7-year period. Average live-weight gain for the 7 years was 136 kg/head/year, which is above expected levels for this vegetation type. Reasons suggested for this animal performance are the use of a stocking rate more lenient than the district average and above-average winter rainfall received during the 7 years of this demonstration project. Removing trees doubled the pasture dry matter yield, which subsequently allowed a doubling of stocking rate …
Forage Production From In Situ Herbicide Treatment Of Semi-Arid Woodlands And Scrub Regrowth,
2025
DowElanco Australia Ltd
Forage Production From In Situ Herbicide Treatment Of Semi-Arid Woodlands And Scrub Regrowth, A R. Murphy, C O. Love, G W. Fossett
IGC Proceedings (1977-2023)
The response of native pastures after stem injection of eucalypt woodlands with picloram-triclopyr herbicide in 1986 was Investigated at 2 locations in Queensland over 18 months, Treatments were fenced to exclude half the plots from grazing by cattle. At Rolleston (good rainfall) dry matter grass response from grazed and ungrazed plots was 2- to 3-fold more than in untreated plots 4-18 months after treatment. At Mundubbera (low rainfall) picloram-triclopyr gave 2- to 5-fold increases in grass dry matter 3-18 months in ungrazed plots and 3-9 months in grazed plots. At both sites plclorarn-triclopyr gave quicker nnd greater grass response than …
Evaluation Of Animal Productivity And Pasture Yield After Treatment Of Brigalow (Acacia Harpopylla) Regrowth With Tebuthiuron,
2025
DowElanco Australia
Evaluation Of Animal Productivity And Pasture Yield After Treatment Of Brigalow (Acacia Harpopylla) Regrowth With Tebuthiuron, G W. Fossett, P C. Venamore
IGC Proceedings (1977-2023)
Brigalow (Acacia harpophylla) regrowth was aerially treated with 2.0 kg/ha tebuthiuron (Graslan TM) at Blackwater, Australia in November 1989. Control of brigalow regrowth increased in grass production 2- fold, which resulted in dramatic animal live-weight gains. The liveweight advantage of steers grazing the tebuthiuron treated area was 31 kg/head compared with similar steers grazing the control paddock at similar stocking rates. After 20 months this advantage enabled 44% of stock to be marketed at premlum prices. A subset of steers implanted with a long-term hormonal growth promotant (HGP) (Compudose400™) and grazing the tebuthiuron-treated paddock recorded a 75 kg …
Competitive Effects Of Trees On Pasture Are A Function Of Rainfall Distribution And Soil Depth,
2025
Queensland Department of Primary Industries
Competitive Effects Of Trees On Pasture Are A Function Of Rainfall Distribution And Soil Depth, J C. Scanlan, G M. Mckeon
IGC Proceedings (1977-2023)
A pasture production model was modified to account for the effect of tree water use on pasture production in woodlands of norJhern Australia. Simulation experiments with the model indicate that competition for water explains the effect of trees on pasture production. Trees compete for water most strongly (I) in shallow soils; (2) when tree roots are shallow; and (3) when intra-seasonal dry periods reduce the amount of water available for transpiration.
Deforestation In The Savanna Context: Problems And Benefits For Pastoralism,
2025
Queensland Department of Primary Industries
Deforestation In The Savanna Context: Problems And Benefits For Pastoralism, W H. Burrows
IGC Proceedings (1977-2023)
Deforestation is discussed from a savanna perspective, rather than in the usual rain forest connotation. Reasons for removing trees and shrubs from savannas are outlined with emphasis placed on the impacts that tree clearing has on livestock production. Other benefits and possible adverse consequences of removing woody plants are detailed. It is suggested that the importance of trees ln maintafning nutrient flows in grazed savanna may be overstated. Problems that arise from clearing trees from savannas often result from a lack of preclearing planning or post-clearing management, rather than the clearing operation Itself.
Deforestation For Pasture In The Humid Tropics: Is It Economically And Environmentally Sound In The Long Term?, E Adilson Serrao, C Uhl, D C. Nepstad
IGC Proceedings (1977-2023)
During the past 5 decades, the rate of tropical forest conversion has accelerated in response to economic pressures, population growth, technological development, and prpgrammes and incentives to open land for development. Deforestation rates rose substantially through the I 980s, and were highest in Africa ( 1.7% ), followed by Asia (1.4%) and Latin America (0.9%). The greatest extent of deforestation, however, was In Latin America, especially in the Amazon, where much of the deforestation was for pasture-based cattle development. Although forest conversion for ranching has been routinely criticised because of the ecological and socioeconomic implications associated with it, cattle herds …
A Legume Ley System In Australia's Semi-Arid Tropics,
2025
QDPI/CSIRO
A Legume Ley System In Australia's Semi-Arid Tropics, R L. Mccown, K Thiagalingam, T Price, P S. Carberry, R K. Jones, N P. Dagliesh, D.C I. Peake
IGC Proceedings (1977-2023)
A large part of the Australian continent is semi-arid and tropical. While extensive beef cattle grazing is the most significant agricultural industry in this region, there Is some potential for dryland cropping. There are strong economic and- ecological reasons for exploring the possibility of a no-till tropical ley system. Work at Katherine, Northern Territory, found that a ley system based on Stylosanthes hamata cv. Verano showed considerable promise based on both contributions to dry-season animal performance and nitrogen contribution to succeeding coarse grain crops. Subsequent research and development in the wetter Douglas-Daly district of the Northern Territory has demonstrated even …
Hardseededness Of Medicago Polymorpha Under Field Conditions In The Subhumid Mediterranean Zone Of Chile, Julia R. Avendano, Alejandro L. Del Pozo, Carlos M. Ovalle
IGC Proceedings (1977-2023)
To improve knowledge in the establishment and self-regeneration of medics grown in rotation with wheat in Chile, the long-term ambiental softening of medic seed is being studied. In March, (i) 72 samples of 100 pods each, were broadcast on the soil surface In plots of 20x20 cm, surrounded by a wood frame, and (ii) 12 samples were placed in a similar way, but the pods were buried at 1-2 ·cm. /11 sitr,, or field germination was recorded, and the germinated seeds destroyed. In (i), every 2 months during the first to fourlh softening season (SS), and in (ii), each March …
Role Of Gramineous Species In Cereal-Annual Legume Farming Systems,
2025
University of Adelaide
Role Of Gramineous Species In Cereal-Annual Legume Farming Systems, G N. Roberts, P G. Tow, E D. Carter
IGC Proceedings (1977-2023)
Three pasture types (volunteer annual grass+medic, grass-free medic and oat+volunteer grass+medic) were compared at 2 stocking rates (8.4 and 12.6 DSE) with grazing Merino wethers. The oat variety is resistnnt to both Gaeumannomyces graminis (take-all) and Heterodem avenae (cereal cyst nematode), important root diseases of cereals. Four harvests were taken during early winter. The oat + grass + medic pasture type had a faster growth rate and maintained higher levels of available pasture on all sampling occasions (July to September). The yields of the grass and medic components were significantly reduced in the oat+grass+medic treatment from the second harvest onwards. …
Digitaria Milanjiana Ley Pasture For Banana Cropping In Tropical North Queensland, Australia,
2025
Queensland Department of Industries
Digitaria Milanjiana Ley Pasture For Banana Cropping In Tropical North Queensland, Australia, T J. Hall, G D. Walduck, R W. Walker
IGC Proceedings (1977-2023)
The burrowing nematode (Radopholus similis) is a major economic pest of bananas in the wc;t tropics of Queensland. It is expensive to control, reduces banana yields and can reduce the economic life of a crop. Current pasture grasses cannot be used in leys because they are hosts to the nematode. Introduced pasture grasses (143 accessions) were evaluated for their environmental adaptation, burrowing nematode resistance, and weed control and erosion protection ability. Digitaria milanjiana CPI 59745 was the most successful accession and it was released as cultivar Jarra. Establishment methods for planting stolon material were developed.
Yields And Nitrogen Contents Of Maize Receiving Fertilizer Nitrogen Or After Alfalfa And Red Clover,
2025
University of Kentucky
Yields And Nitrogen Contents Of Maize Receiving Fertilizer Nitrogen Or After Alfalfa And Red Clover, M Collins
IGC Proceedings (1977-2023)
Two experiments compared alfalfa (Medicago sativa L.) and red clover(Trifolium pratense L.) genotypes for supplying N to an ensuing maize (Zea mays L.) crop. A non-fixing alfalfa genotype, which nodulates but fixes no N, served as a control crop. Nitrogen-fertilised maize received 0, 7S, ISO or 22S kg/ha of N annually as NH4NO3• Maize was seeded into I-year-old legume stands killed by N• (phosphono-methyl) glycine isopropylamine. Non-fixing alfalfa yielded 6 t/ha of forage in the first year compared with 9 t/ha or more for normal cultivars. Two-year mean maize grain yields after Dart alfalfa were 9.2 t/ha and …
Effects Of Short-Term Rotations Of Monocultures And Mixtures Of Legumes And Grasses With Rice In The Subtropical Zone Of South-Western China,
2025
Sichuan Agricultural University
Effects Of Short-Term Rotations Of Monocultures And Mixtures Of Legumes And Grasses With Rice In The Subtropical Zone Of South-Western China, S R. Zhou, Y G. Yu, K Mao, X M. Gan, Z L. Pu
IGC Proceedings (1977-2023)
Five short-term rotation systems of monocultures and mixtures of legumes and grasses with rice, i.e., Medicago hispida ➔ rice, Trifolium repens cv. Ladino ➔ rice, Astragalus sinicus + lolium multiflorum ➔ rice, Medicago hispida + Lolium multiflorum ➔ rice and Trifolium repens cv. Ladino + Lolium multiflorium ➔ rice, were selected from 8 evaluated in this study in the subtropical zone of south-western China. The average results for these rotational types per year were: forage dry matter 3,63 tlha, forage crude protein 727 .5 kg/ha, metabolisable energy 22.lx!03 MJ/ha, in vitro organic matter digestibility of forages 72.84%, rice yield 7.4 …
Prospects For More Sustainable Cropping Systems In Central Italy Based On Subterranean Clover As A Cover Crop,
2025
Universita della Tuscia
Prospects For More Sustainable Cropping Systems In Central Italy Based On Subterranean Clover As A Cover Crop, F Caporali, E Campiglia, R Paolini
IGC Proceedings (1977-2023)
A range of possibilities for increasing long-term sustainability of cropping systems in the mediterranean environment of central Italy is presented, supported by experimental evidence on the use of subterranean clover (Trifolium subterraneum) as living mulch and green manure in a common cash crop rotation (wheat-sunflower). The annual self-regenerating legume proved to have potential for inducing a significant shift towards a less energy-intensive management of such.a specialised cropping system, and also provided innovative and flexible patterns of crop sequences. Tillering capacity of wheat turned out to be a crucial element for sub clover living mulch to act successfully on …
