Balancing Water Use Efficiency And Milk Production In The Sub-Tropics,
2023
The University of Queensland, Australia
Balancing Water Use Efficiency And Milk Production In The Sub-Tropics, Mark N. Callow, S. K. Kenman
IGC Proceedings (1977-2023)
Queensland dairy farmers have had to confront in the last 5 years deregulation of the milk pricing system, resulting in a 25% reduction in farm gate price for milk in the year 2000, and drought. Many storage dams are significantly below capacity and regulatory authorities have imposed restrictions on irrigation water allocations. Major changes in farm business strategies were needed to overcome the shortfall in milk income. Production systems had to change to deliver more milk more efficiently and become more profitable. A farmlet study was developed in the sub-tropical dairy region of Queensland to evaluate 5 very different farm …
Rooting Pattern Distribution And Spatial Variability Of Italian Ryegrass (Lolium Multiflorum Lam) In A Mediterranean Region,
2023
University of Évora, Portugal
Rooting Pattern Distribution And Spatial Variability Of Italian Ryegrass (Lolium Multiflorum Lam) In A Mediterranean Region, M. R. G. Oliveira, F. C. Brasil, Q. I. Monteiro, R. O. P. Rossiello
IGC Proceedings (1977-2023)
It is estimated that less than 10% of the studies on pastures and forages have evaluated the subterranean biomass production. The objective of this study was to evaluate for a Mediterranean region the rooting characteristics and spatial variability of Italian ryegrass (Lolium multiflorum Lam) under two different soil water status conditions.
Effect Of Timing And Intensity Of Drought On Perennial Ryegrass Seed Yield,
2023
New Zealand Institute for Crop & Food Research Limited, New Zealand
Effect Of Timing And Intensity Of Drought On Perennial Ryegrass Seed Yield, R. J. Martin, R. N. Gillespie, S. Maley
IGC Proceedings (1977-2023)
Perennial ryegrass seed worth about $50 million is produced annually in Canterbury, New Zealand (Rowarth 1998). Ryegrass seed production in New Zealand is often affected by drought, reducing both seed number and seed size (Rolston et al., 1994). Irrigation management recommendations are not currently available for farmers growing ryegrass seed crops. To quantify the effect of water stress on perennial ryegrass seed yield, we carried out an experiment in a rainshelter where rainfall was excluded from experimental plots otherwise exposed to normal weather (Martin et al., 1990).
Study On Transpiration Rates Of Vicia Villocea And Bromus Inermis Species,
2023
Tarbiat Modares University, Iran
Study On Transpiration Rates Of Vicia Villocea And Bromus Inermis Species, S. H. R. Sadeghi, N. Rahimzadeh
IGC Proceedings (1977-2023)
Ecohydrology is concerned with the interaction between the hydrological and plant processes. Some aspects of the hydrologic cycle, such as transpiration and interception have received little attention owing to difficulties in field measurements. Quantifying the components of water balance for a watershed is crucial for understanding the dominant hydrologic processes occurring in a basin (Flerchinger & Cooley, 2000). Water use by vegetation is controlled by the water uptake by roots, the transfer of liquid water through plants and vapour loss from the leaf surfaces by the opening and closure of the stomata (Roberts, 2000) i.e. transpiration. Comparison of transpiration of …
Influence Of Water Stress On Root/Cladode Ratio And Water-Use Efficiency Of Opuntia Ficus-Indica And O. Robusta,
2023
University of the Free State, South Africa
Influence Of Water Stress On Root/Cladode Ratio And Water-Use Efficiency Of Opuntia Ficus-Indica And O. Robusta, Hennie A. Snyman
IGC Proceedings (1977-2023)
Due to the regular occurrence of drought in southern Africa, there is a need for more research on drought tolerant fodder plants such as Opuntia (cactus pear) species. In contrast with the cladode system, the roots of cactus pear have received little attention, however, they certainly differ from other plants, as they develop xeromorphic characteristics, enabling the plant to survive prolonged periods of drought (Nobel, 1988). The influence of different water applications was evaluated in terms of root and cladode mass, water-use efficiency (WUE) and root length for one-year-old plants of Opuntia ficus-indica (cultivar Morado) and O. robusta (cultivar Monterey).
Variability In Tolerance To Water Stress By Holcus Lanatus L., Bromus Valdivianus Phil. And Agrostis Capillaris L. Accessions,
2023
Universidad Austral de Chile, Chile
Variability In Tolerance To Water Stress By Holcus Lanatus L., Bromus Valdivianus Phil. And Agrostis Capillaris L. Accessions, Ignacio F. López, Oscar A. Balocchi
IGC Proceedings (1977-2023)
Holcus lanatus L. (Hl), Bromus valdivianus Phil. (Bv) and Agrostis capillaris L. (Ac) are frequently present in the naturalised pasture of the Chilean humid region, which has a summer drought with two distinguishable areas according to average summer rainfall: a Northern area (Long summer drought, LSuD: 136-186 mm;) and a Southern area (Short summer drought, SSuD: 186-338 mm). It was hypothesised that plant species have colonised areas with different water deficits during summer through differentiated drought tolerance, which would imply ecotype generation.
Development Of A Breeders’ Toolkit For Drought Resistance In A Lolium/Festuca Hybrid,
2023
Institute of Grassland and Environmental Research, UK
Development Of A Breeders’ Toolkit For Drought Resistance In A Lolium/Festuca Hybrid, J. Humphreys, I. P. Armstead, M. O. Humphreys
IGC Proceedings (1977-2023)
Lolium multiflorum (Lm) is considered an ideal grass for European agriculture. However, existing high-quality forage Lm cultivars have been bred for intensive systems in benign environments, and have proved to be insufficiently robust to meet many of the environmental challenges that face extensive agriculture in more extreme conditions. Genes for persistency, tolerance of cold, drought and poor soils, can be found in currently under-exploited native Festuca ecotypes. These Festuca ecotypes cannot however compare with Lm cultivars for productivity or quality of forage under favourable conditions. Festuca glaucescens (Fg) is of Mediterranean origin and as such is adapted to drought and …
Impact Of Land Use On Water Quality In River Njoro Watershed, Kenya,
2023
Egerton University, Kenya
Impact Of Land Use On Water Quality In River Njoro Watershed, Kenya, W. A. Shivoga, M. Muchiri, S. Kibichi, J. Odanga, S. N. Miller, T. J. Baldyga, C. M. Gichaba
IGC Proceedings (1977-2023)
Water resources within the River Njoro watershed have become degraded due to high population growth rate and change in land use upsetting environmental stability. Land cover classification using Landsat images (Baldyga et al., 2004) shows loss of about 20% of forested areas between 1986 and 2003 in the watershed. The forested and large-scale farm areas have been converted mainly into small-scale mixed agriculture and human settlements. These changes have impacted negatively on the ecological integrity and hydrologic processes in the watershed (Shivoga, 2001) but little is known about the influence of specific land uses on water quality of the …
Phosphorus Transfer To River Water From Grassland Catchments In Ireland,
2023
Teagasc, Ireland
Phosphorus Transfer To River Water From Grassland Catchments In Ireland, H. Tunney, P. Jordan, G. Kiely, R. Moles, G. Morgan, P. Byrne, W. Menary, K. Daly
IGC Proceedings (1977-2023)
In Ireland it is estimated that at least half of phosphorus (P) loss to water is from agricultural sources and National and European Union policy and legislation aim at reducing phosphorus (P) loss to water in order to reduce eutrophication. In Ireland, the average soil test P (STP) levels increased ten-fold, from less than 1 to over 8 mg Morgan P per l soil over the past 50 years, reflecting increased P inputs in fertiliser and animal feed. One of the main objectives of this three-year research programme, started in 2001, was to investigate P loss to water in grassland …
Grazing Management Impacts On The Riparian Zone And Water Quality,
2023
Ellinbank Research Institute, Australia
Grazing Management Impacts On The Riparian Zone And Water Quality, S. R. Aarons, A. Melland, C. J. P. Gourley
IGC Proceedings (1977-2023)
Inappropriate farm management activities such as stock access to creeks, and poor fertiliser and effluent management can negatively impact riparian zones and waterways, contributing to increased in-stream nutrient, sediment and microbiological loads and loss of riparian biodiversity, amongst other impacts. Nutrient budgets for dairy systems indicate that on-farm nutrient accumulation and redistribution is common (Gourley 2004), which in large part is due to the uneven distribution of dairy cow dung and the nutrients they contain (Aarons et al., 2004). The 'Gippsland Dairy Riparian Project Environmental Monitoring module' was established in Jan. 2003 to monitor the impact of …
Denitrification Under Pastures On Permeable Soils Helps Protect Ground Water Quality,
2023
USDA-Agricultural Research Service
Denitrification Under Pastures On Permeable Soils Helps Protect Ground Water Quality, M. P. Russelle, B. A. Browne, N. B. Turyk, B. Pearson
IGC Proceedings (1977-2023)
Pastures have been implicated in ground water contamination by nitrate, especially in humid regions with thin or sandy soils (Stout et al., 2000). Significant losses can occur even under low N input, because available N from excreta patches often exceeds plant uptake capacity. Lack of evidence that appreciable nitrate leaching was occurring in established Midwestern USA pastures led us to test the hypothesis that denitrification was preventing or remediating nitrate loading. Higher denitrification rates have been found in the relatively limited number of trials since Ball & Ryden (1984) first reported the significance of this process in pastures.
Implementation, Participation And Evaluation Of A Voluntary Water Quality Protection Program For Grazingland Owners And Managers,
2023
University of California, Davis
Implementation, Participation And Evaluation Of A Voluntary Water Quality Protection Program For Grazingland Owners And Managers, Mel R. George, J. M. Harper, S. R. Larson, R. E. Larsen, N. K. Mcdougald, D. J. Lewis
IGC Proceedings (1977-2023)
In 1990, California's range livestock industry began working with the state's water quality regulatory agency to develop a voluntary producer participation programme to protect water quality on privately owned grazinglands. In 1995 they implemented a voluntary programme of surface water protection supported by extension education and technical assistance conducted by University of California and USDA Natural Resources Conservation Service. Past studies have shown that education programmes are crucial to voluntary pollution control programmes in agriculture (EPA 1990) and that ranchers will change grazing management practices in response to extension education programmes (Richards and George 1996). The objective of this project …
Profitable And Sustainable Grazing Systems For Livestock Producers With Saline Land In Southern Australia,
2023
South Australian Research and Development Institute, Australia
Profitable And Sustainable Grazing Systems For Livestock Producers With Saline Land In Southern Australia, Nick Edwards, D. G. Masters, Edward G. Barrett-Lennard, M. Hebart, M. Mccaskill, W. King, W. Mason
IGC Proceedings (1977-2023)
Dryland salinity affects over 2.5 M ha in Australia, mostly in southern states and is expanding at 3-5% per year (NLWRA, 2001). The prognosis is for considerable expansion of the area affected by salinity and waterlogging (1217 M ha at equilibrium), because groundwater levels continue to rise and only small-scale land management programmes have been implemented. In addition, many waterways are increasingly saline, especially in the Murray Darling Basin and in Western Australia (WA). Sustainable Grazing on Saline Land (SGSL) addresses the need to make productive use of saline land and water resources. Its research component operates at 12 sites …
A New Perennial Legume To Combat Dryland Salinity In South-Western Australia,
2023
University of Western Australia, Australia
A New Perennial Legume To Combat Dryland Salinity In South-Western Australia, L. W. Bell, M. A. Ewing, M. Ryan, S. J. Bennett, G. A. Moore
IGC Proceedings (1977-2023)
Dryland salinity has devastated large tracts of productive land in Australia. This has resulted from the clearing of native perennial vegetation and its replacement with annual crops and pastures. As annual plants are shallow rooted and only use water during their winter-spring growing season, unutilised rainwater leaks into groundwater tables which rise and bring stored salt to the soil surface. The adoption of deep rooted perennial pasture plants that increase the water use can help to manage dryland salinity whilst maintaining productivity. However, new plants are needed as few perennial pasture options currently exist. Preliminary research into the potential of …
Selecting Grassland Species For Saline Environments,
2023
Cooperative Research Centre for Plant-Based Management of Dryland Salinity, Australia
Selecting Grassland Species For Saline Environments, Mary-Jane E. Rogers, A. D. Craig, T. D. Colmer, R. Munns, S. J. Hughes, P. M. Evans, P. G. H. Nichols, R. Snowball, D. Henry, J. Deretic, B. Dear, M. Ewing
IGC Proceedings (1977-2023)
In Australia, around 5.7 million hectares of agricultural land are currently affected by dryland salinity or at risk from shallow water tables and this figure is expected to increase over the next 50 years (LWRA, 2001). Most improved grassland species cannot tolerate the combined effects of salt and waterlogging and, therefore, the productivity of sown grasslands in salt-affected areas is low. However, there is potential to overcome the lack of suitably adapted fodder species by introducing new, salt and waterlogging-tolerant species and by diversifying the gene pool of proven species. Potential species include exotic, naturalised and native Australian grass, legumes, …
Early Spring Surface Runoff From Grassland And Arable Land,
2023
Mendel University of Agriculture and Forestry, The Czech Republic
Early Spring Surface Runoff From Grassland And Arable Land, S. Hejduk, K. Kasprzak
IGC Proceedings (1977-2023)
Surface runoff is regarded as an undesirable phenomenon because it deprives plants and soil of precipitation water and reduces its penetration underground. It is also the cause erosion and flooding. The occurrence and depth of a frozen soil layer is the main factor which determines the amount of surface runoff in winter. A well-developed surface and/or sub-surface layer of frozen soil is practically impenetrable for water. This layer results from ice-forming processes, which are influenced by snow melting due to diurnal fluctuations in temperature in early spring, partial thaws, winter rainfalls, and thermocapillary processes taking place in frozen soil.
Effect Of Mineral Nutrition On Red Clover Leaf Area Index,
2023
Faculty of Agriculture, Serbia
Effect Of Mineral Nutrition On Red Clover Leaf Area Index, B. Cupina, P. Erić, S. Vasiljević, V. Mihailovic, D. Milic
IGC Proceedings (1977-2023)
The legume red clover (Trifolium pratense) fixes its own nitrogen (N), but requires P and K fertilisation. There are no recent reliable data in the domestic literature, on the amounts of P and K recommended to farmers; present recommendations are often either inadequate or excessive. Red clover mineral nutrition is significantly affected by soil and weather conditions (Taylor & Quesenberry, 1996). The objective of our twoyear study was to enable rational fertiliser application in accordance with soil type and agro ecological conditions.
Sources Of N Used For Growth Following Defoliation In Panicum Maximum1,
2023
EMBRAPA, Brazil
Sources Of N Used For Growth Following Defoliation In Panicum Maximum1, Patricia M. Santos, B. Thornton, M. Corsi
IGC Proceedings (1977-2023)
The nitrogen (N) supplied to growing leaves from root uptake and mobilisation from senescing tissues may be reduced following defoliation. However, morphological adaptation of the shoot to prior defoliation occurs (Matthew et al., 2002), which may affect the potential N supply from remaining leaves. This study determined the degree to which plants of Panicum maximum utilised current root uptake and mobilisation to supply N to growing leaves and side tillers following defoliation.
Growth Characteristics Of Kikuyu Grass With Different Sources And Doses Of Phosphorus,
2023
Universidade Federal de Lavras, Brazil
Growth Characteristics Of Kikuyu Grass With Different Sources And Doses Of Phosphorus, José C. Pinto, Í. P. A. Santos, A. E. Furtini Neto, A. R. Morais, E. E. Mesquita, D. J. G. Faria, I. F. Andrade
IGC Proceedings (1977-2023)
Growth is defined as the increase in size, volume and mass as a function of time. Growth analysis allows evaluating the final growth of the plant as a whole and the contribution of the different organs in total growth (Benincasa, 1988). The experiment had as objective to evaluate specific leaf area (SLA), leaf area per unit of leaf DM, leaf area ratio (LAR), leaf area per unit of whole plant DM, leaf weight ratio (LWR), leaf weight per unit of plant weight, leaf area index (LAI), leaf area per unit of soil area, leaf/stem ratio (LSR), leaf weight per unit …
Sustainable Pastures For The High Altitude Andean Tropics Of Colombia,
2023
Universidad Nacional de Colombia, Colombia
Sustainable Pastures For The High Altitude Andean Tropics Of Colombia, E. Cárdenas, L. Panizzo
IGC Proceedings (1977-2023)
Dairy production systems in the high altitude Andean region of Colombia (>2.600 m.a.s.l.) use large amounts of nitrogen (N) fertilisation. Due to the inefficient use of N by the grass, it contaminates surface and ground water resulting in the eutrophication of lakes and rivers. It contributes to increased atmospheric NOx, greenhouse gas and acid rain. Therefore, the effect of different species of grasses mixed with Lotus corniculatuson N soil balance was evaluated.
