Agronomy and Crop Sciences Commons^™

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, 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, 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, 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, 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, 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, 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, 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, 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, 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, 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, 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, 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, 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, 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.

Seasonality Of Growth In Grass-Clover Swards Under Repetitive Nitrogen Application, M. Nassiri, A. Elgersma

IGC Proceedings (1977-2023)

The cohabitation of grass and clover is possibly due to asynchrony in their growth patterns, and to the beneficial effects of fixed nitrogen (N) on grass. Incompatibility of clover persistence with N fertilisation has been frequently reported (Nassiri and Elgersma, 2002). However, limited information is available regarding the effect of repetitive application of N in mixed swards. This research aims to study the balance between species in response to application of increasing rates of N throughout the growing season.

Effects Of Soil Compaction By Animal Trampling On Growth Of Agropyron Repens, M. R. Chaichi, B. Ataeian, M. Mohseni Saravi

IGC Proceedings (1977-2023)

Animal trampling is the most important factor that increases soil compaction beyond the soil elastic property in rangelands under heavy grazing intensities (Lull, 1959). The complicated ecological interactions in a rangeland ecosystem make it difficult to predict the impact of trampling under different conditions. However, soil properties and vegetation composition are sensitive to different grazing management practices. This research, which was carried out in simulated conditions, sought to establish the contribution of soil compaction resulting from animal trampling over a long period to the decline in rangeland condition.

Effect Of Fertilisation With Macro And Micronutrients On The Mineral Content Of Leucaena Leucocephala, S. Camacaro

IGC Proceedings (1977-2023)

The Venezuelan cattle industry has been developed in areas with soil limitations, causing a negative impact on animal production, since the pastures are of medium to low quality and quick maturation (Chacón, 1996). On the other hand, forage legumes have been introduced to improve the nutritive value of the biomass on offer. Growing interest has been shown in Leucaena leucocephala in recent years due to its multiple benefits (Duguma et al., 1988). However the use of varieties not adapted to acid soils can be a problem, largely due their low tolerance to the toxicity of the aluminium and to …

Effects Of Applied Quantity Of Phosphorus Fertiliser On Phosphorus Content In Plant Tissues Of Lucerne (Medicago Sativa) And Seed Yield In North-Western China, Y. W. Wang, J. G. Han, S. M. Fu, Y. Zhong

IGC Proceedings (1977-2023)

Phosphorus concentration in plant tissue can be a useful index of P deficiency in lucerne, P fertiliser recommendations and monitoring of effectiveness of current P fertiliser practices (Jacobsen & Surber, 1995). The objective of this study was to measure P concentration in different lucerne plant parts and seed yield in relation to P fertiliser application rates in order to improve recommendations for lucerne seed production.

Influence Of P Fertility And Grazing On Plant Species In A Temperate Australian Pasture, Jacqueline O. Hill, R. J. Simpson, A. D. Moore, J. T. Wood, D. F. Chapman

IGC Proceedings (1977-2023)

Graziers in temperate Australia are increasing their use of P fertiliser so they can run more stock and maintain profitability. However, intensification changes grassland botanical composition and perennial grass cover can be reduced. Perennial grasses are important because they improve production stability, reduce deep drainage and slow the rate of soil acidification. This study examined how P fertility and grazing affected the botanical composition of pasture based on Phalaris aquatica, a key perennial grass in south-eastern Australia.

Forage Quality And Yield Of Berseem Clover And Annual Ryegrass Grown In Pure And Mixed Stands In Relation To Different N Application Rates, C. Scarpello, L. Stringi, G. Amato, D. Giambalvo, P. Trapani, C. Attardo

IGC Proceedings (1977-2023)

Grass-legume mixtures offer several advantages over monocultures in forage-animal production systems (Haynes, 1980). In fact, in grass-legume mixtures forage yield and quality are generally higher compared to grass monocultures also due to more efficient soil N-utilisation (Ta & Faris, 1987); furthermore grasses often utilise some of the N fixed by legumes (Malhi et al., 2002). Legumes do not generally require the addition of N fertiliser due to symbiotically fixed N, but the yield of the grass component in a mixture may be further improved with N application. The objective of this study was to investigate forage yield and quality …

Effect Of Different Phosphorous Sources And Levels On The Productive Behaviour Of A Lotus Pedunculatus Cv. Grasslands Maku Oversown Pasture, R. E. Bermúdez, W. Ayala

IGC Proceedings (1977-2023)

The organic meat production protocol of Uruguay (INAC, 2003) requires that the animals graze pastures that receive no chemical fertilisers. The oversown legume pastures in Uruguay used to be fertilised with soluble phosphorous (P) sources that are not accepted by the protocol. The relative efficiency of different P sources would be useful data for farmers. This information is not available for the acid soils of the eastern region of Uruguay. Lotus pedunculatus cv. Grasslands Maku is one of the most adapted legumes to be included in this type of pasture, as the sown area has increased in the last few …

Effects Of Sowing Date And Phosphorus Fertiliser Application On Winter Survival Of Lucerne Cv. Aohan In The Northern Semi-Arid Region Of China, Z. L. Wang, Q. Zh. Sun, Y. W. Wang, Zh. Y. Li, Sh. F. Zhao

IGC Proceedings (1977-2023)

In the northern semi-arid region of China, winter survival is always a limiting factor for lucerne production, because low temperatures and a dry climate in winter (Zhou et al., 1993; Ma, 2000; Sun & Gui, 2001; Sun et al., 2003). An experiment was conducted to find an appropriate sowing date and P application rate in order to improve lucerne winter survival.

Organic And Mineral Fertilisation Of Temporary Grassland, Michele Maiorana, F. Montemurro, F. Fornaro

IGC Proceedings (1977-2023)

In Italy, the need to reduce the application of chemical fertilisers and to dispose of different kinds of bio-wastes (municipal solid waste (MSW), olive mill waste, distiller's grains) has led to more compost being made from these materials. Since 1995 our Institute has carried out several studies on different crops. The results obtained so far for grain and industrial crops (Montemurro et al., 2003; Maiorana et al., 2004) appear very interesting. But rarely have the composts been applied to fodder crops. Therefore, this research is aimed to evaluate the effect of MSW-compost on temporary grassland of cocksfoot ( …

Effect Of Animal Manure On Forage Yield And Quality Of Pangolagrass And Soil Fertility, Fu‐Hsing Hsu, Kuoyuan Hong, C. H. Hsieh

IGC Proceedings (1977-2023)

Animal wastes may cause environmental pollution. Lu & Hsu (2004) reported that N utilisation in the manure by pangolagrass was 10-28%. Objectives of this study were to determine the effect of animal manure on forage yield and quality of pangolagrass and soil fertility.

Effect Of Mineral Fertiliser Levels On The Yield Quality Of Perennial Ryegrass, S. R. Bumane, Aleksandr Adamovich

IGC Proceedings (1977-2023)

Perennial ryegrass is a short-lived bunch-grass with shallow root system. The plant is nutritious and palatable and stands up to hard grazing. It will not do well under poor conditions, where fertility or rainfall is low. Perennial ryegrass is a major component in different seed mixtures that are used for grassland management and forage production. This plant is the predominant component in nearly all pasture mixtures, with perennial ryegrass and white or red clover forming the basis for permanent pasture for dairy production and cattle. This grass species plays an important role in grassland productivity and forage quality. Ryegrass requires …

Effects Of Cattle Slurry, Their Solid And Liquid Fractions And Mineral N Fertilizers On Italian Ryegrass And Maize Forage Yield, H. Trindade, J. Coutinho, N. Moreira

IGC Proceedings (1977-2023)

Solid-liquid slurry separation techniques expand possibilities to improve slurry use efficiency and to reduce its negative environmental impact. These possibilities arise from the different behaviour of the two fractions concerning the release of nutrients, namely nitrogen (N), due to different C:N ratios (≈30 for the solid fraction and ≈7 for the liquid fraction).

The aim of this work was to evaluate the effect of cattle-slurry and their solid and liquid fractions applied at sowing time of Italian ryegrass (Lolium multiflorum cv. Andrea) and forage maize on crop dry matter (DM) yield. In the NW region of Portugal these two …

Combinations Of Nitrogen And Sulphur For Signal Grass Yield, F. A. Monteiro, C. P. Silveira

IGC Proceedings (1977-2023)

Signal grass (Brachiaria decumbens) is grown in Brazilian pastures, and the increase in forage yield of such pastures is achieved by fertilization. Nitrogen (N) is the nutrient mostly demanded for increasing grass productivity, and its utilization creates a demand for other nutrients, such as sulphur (S). These two nutrients are well related in plant metabolism, but the S nutrition of signal grass must be better understood. The use of a fractional factorial makes possible the study of several rates of these two nutrients, that combined with the response surface methodology allows anyone to find out the responses to …

Supplementation Of Cattle With Rock Phosphate And Urea Treated Straw To Improve Manure Quality And Crop Yields In The Sahel Zone Of Senegal, Maimouna Cissé, M. N’Diaye, C. M. N'Dione

IGC Proceedings (1977-2023)

Mineral deficiencies are a major constraint in improving animal production and crop yield in the Sahel zone (Cissé et al., 1996). Millet (Pennisetum glaucum) and groundnut (Arachis hypogaea) are two major food and cash crops in this zone. The purpose of this study was to assess effects of supplementing grazing cattle with rock phosphate and nitrogen enriched diets on animal performances, and the effects of the application of their manure on crop yield in a pearl millet-groundnut rotational system located in N Senegal.

Nitrogen Response Of Spring And Winter Wheat To Biosolids Compared To Chemical Fertiliser, W. Kato, O. T. Carton, D. Mcgrath, H. Tunney, W. E. Murphy, P. O'Toole

IGC Proceedings (1977-2023)

Irish sewage sludge production was over 30,000 t/year in the 1990s (EPA, Ireland, 2003). Application to agricultural land is a management option for this organic material as it results in the recycling of the nutrients they contain for crop production. The EU Directive (91/271/EEC) encourages the recycling of sewage sludge as biosolids to agriculture. However, up to 1999, only about 5 % of biosolids produced was applied to agricultural land. In this study, several biosolids and a chemical fertiliser were used to assess N availability for spring and winter wheat (Triticum aestivum) production in a pot experiment.