Weed Science Commons^™

New Insights Into The Nutritional Value Of Grass, D. H. Rearte

IGC Proceedings (1977-2023)

Key points

1. The rumen environment in cattle grazing high quality forage is different to that reported for cattle fed indoors with diets based on processed feedstuffs.
2. Temperate pasture is an excellent source of nutrients for ruminants but a high energy:protein imbalance can occur when it is offered at the stage of optimal digestion.
3. Beef and milk produced on grass in temperate regions have a composition with nutritional advantages over beef or milk produced in indoor systems based on concentrate.
4. Increasing water soluble carbohydrate content of grasses would diminish environmental contamination by reducing the excretion of urea through the urine.
5. Increasing …

Plant And Sward Characteristics To Achieve High Intake In Ruminants, W. J. Wales, C. R. Stockdale, P. T. Doyle

IGC Proceedings (1977-2023)

Key points

1. Intake is affected by complex interactions between signals from the digestive tract, intermediary metabolism and energy supply, and behavioural signals associated with learned behaviours or sensory signals.
2. The ideal sward needs to have characteristics that are similar to total mixed rations to achieve high intake and animal performance.
3. Genetic manipulation of plants may offer an accelerated rate of plant improvement, but benefits need to be demonstrated in a systems context.

Overview Of Animal Production From Pastures In Ireland, M. J. Drennan, A. F. Carson, S. Crosse

IGC Proceedings (1977-2023)

Key points

The importance of grassland to agriculture in Ireland is indicated by the fact that:

1. Sixty percent of agricultural output is from grassland as cattle, milk and sheep products.
2. Over 90% of the total farmed area is in grass.
3. Livestock are almost entirely dependent on grazed grass for 200 to 235 days of the year.
4. Grass conserved as silage is the main source of fodder in winter.
5. To improve competitiveness changes are continuously taking place, which include:

• increased suckler herd size and a movement to late maturing continental cattle breeds;
• movement in the dairy herd towards Holstein with increased …

Protecting Wa Crops Issue 27 - February 2023, Department Of Primary Industries And Regional Development, Western Australia

Protecting WA Crops

Protecting WA Crops Issue 27 - February 2023 contents:

• Glyphosate alternatives for summer and pre-seeding knockdown weed control
• Meet Crop Protection team member – Cindy Webster

Assessment Of Efficacy And Mechanism Of Resistance To Soil-Applied Ppo Inhibitors In Amaranthus Palmeri, Gulab Rangani, Aimone Perri, Reiofeli A. Salas-Perez, Jens Lerchl, Srikanth Kumar Karaikal, Juan Camilo Velásquez, Nilda Roma-Burgos

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

Resistance to protoporphyrinogen oxidase (PPO) inhibitors in Palmer amaranth is a major concern, given the high selection pressure and increasing number of populations with reduced sensitivity to PPO herbicides in the US. We evaluated the effect of five soil-applied herbicides on Palmer amaranth (Amaranthus palmeri S. Wats.) populations collected in 2014 and 2015 in Arkansas, USA. Soil-applied saflufenacil, sulfentrazone, and flumioxazin reduced the seedling emergence 91–100%; however, fomesafen and oxyfluorfen showed reduced (63–90%) efficacy on some populations. Target-site mutation (TSM) is the major mechanism of resistance to PPO herbicides; therefore, six populations showing resistance to soil-applied fomesafen were selected for …

Grassland Productivity And Water Quality: A 21st Century Issue, David M. Nash, P. M. Haygarth

IGC Proceedings (1977-2023)

1. Irrigation and other changes to the hydrological cycle can increase soil and water salinity.
2. Primary salinisation is a natural process that affects much of Europe, Asia, Africa, the Americas and Australia. Secondary salinisation is caused by human activities such as irrigation and land clearing that mobilise salt stored in the soil.
3. The critical water contaminants exported from grasslands are nitrogen, phosphorus, potential pathogens and sediment.
4. The mechanisms responsible for diffuse pollution from grasslands and mitigation strategies are most effectively investigated using a ‘source-mobilisation-transport’ framework.
5. There is a lack of coherent interaction across discipline boundaries that links pollutant sources to impact. …

Water Resources, Agriculture And Pasture: Implications Of Growing Demand And Increasing Scarcity, M. W. Rosegrant, R. A. Valmonte-Santos, S. A. Cline, C. Ringler, W. Li

IGC Proceedings (1977-2023)

1. Water availability for irrigation is threatened in many regions by rapidly increasing demand for nonagricultural water uses in industry, households, and the environment. The scarcity of irrigation water will not only impact crop production, but also meat production, as much of the pasture used to feed livestock is irrigated.
2. Grassland is caught between two countervailing forces: a requirement for increasing meat demand that boosts the need for additional pasture to support livestock production, and rapidly increasing water scarcity that makes pasture irrigation uneconomical.
3. The most effective means of dealing with water scarcity is likely to be conserving water in existing …

Soil Quality Assessment And Management, M. G. Kibblewhite

IGC Proceedings (1977-2023)

1. Soil quality is related to the capacity of soil to deliver ecosystem services on a sustainable basis.
2. Effective management of soil within grasslands can deliver many benefits to mankind but poor management may cause loss of soil quality from erosion, loss of organic matter, physical deterioration etc.
3. Services are delivered from soil by biological processes. Soil quality depends on the form and condition of the soil habitat. Fixed factors (e.g. texture) are useful for assigning soil to types. Variable factors (e.g. organic carbon) can then be used to assess quality within soil types, by reference to percentiles of the distribution …

Soil Microbial Community: Understanding The Belowground Network For Sustainable Grassland Management, Y. G. Zhu, W. D. Kong, B. D. Chen, Z. B. Nan, P. Christie

IGC Proceedings (1977-2023)

1. In addition to the use of conventional methodologies in soil microbial research, molecular techniques are now being applied to gain insights into the soil microbial community;
2. Plant diversity can exert impacts on soil microbial diversity (through root activities and plant litter etc.), but may in itself be significantly altered by soil properties;
3. Soil microbial diversity largely determines the stability of soil ecosystems under biotic and abiotic perturbations.
4. Management of soil microbial diversity can only be achieved through better understanding their structures and functions.

Grasslands1 For Production And The Environment, David R. Kemp, David L. Michalk

IGC Proceedings (1977-2023)

1. To manage grasslands for production and enhanced environmental values requires a redefinition of the frameworks within which management decisions are made, and a tailoring of practices to suit the ways that farmers operate.
2. Improving the perenniality and permanence of grasslands usually leads to better environmental and production outcomes.
3. There is a case for a more conservative approach to utilising grasslands in order to sustain the functioning of local ecosystems and to improve water quality, nutrient and energy cycling and biodiversity.
4. A landscape rather than paddock focus is more appropriate for meeting current grassland management objectives. Grasslands can be triaged to …

The Potential Of Grassland And Associated Forages To Produce Fibre, Biomass, Energy Or Other Feedstocks For Non-Food And Other Sectors: New Uses For A Global Resource, M. F. Askew

IGC Proceedings (1977-2023)

1. In developed countries increased areas of land will become available for non-food production. Recent reforms of the Common Agricultural Policy will further intensify this trend in Europe.
2. There is potential for grassland and associated species to contribute to large tonnage markets of energy and bulk fibres, to the supply of fermentation products and to speciality markets, but processes and approaches to the market are not as yet developed.
3. There is potential for the establishment of Graminaceous species - specifically for non- food use. For European conditions particular attention is being given to Miscanthus sinensis (Miscanthus), Arundo donax (Giant Reed), Phalaris …

Grasses As Biofactories: Scoping Out The Opportunities, Nick Roberts, K. Richardson, G. Bryan, Christine R. Voisey, W. Mcnabb, T. Conner, M. Christey, R. Johnson

IGC Proceedings (1977-2023)

1. Plant biopharming is set to dominate commercial recombinant protein expression for specific proteins.
2. The choice of plant species depends on a multitude of factors and is determined on a case- by-case basis.
3. As a leaf based expression system grasses would have to compete predominantly with tobacco and alfalfa.
4. The grass-endophyte symbiosis offers a number of unique possibilities for biopharming.

Adoption Of Tropical Legume Technology Around The World: Analysis Of Success, H. M. Shelton, Steven Franzel, M. Peters

IGC Proceedings (1977-2023)

1. Examples of successful adoption of forage legumes are reported from all continents, where they delivered profitability and often provided multipurpose benefits to farmers.
2. Factors vital to successful adoption were: meeting the needs of farmers; building relevant partnerships; understanding the socio-economic context and skills of farmers; participatory involvement with rural communities; and long-term involvement of champions.
3. Organisation of seed supply, achieving scale-up and forming partnerships to implement adoption are key features.
4. Legumes remain an important but under-exploited resource for tropical farming systems. The alternative to legumes will be greater and more costly use of N-fertilisers and purchased protein concentrates.
5. The R&D …

Evolution Of Integrated Crop-Livestock Production Systems, Martin H. Entz, William D. Bellotti, J. M. Powell, S. V. Angadi, W. Chen, K. H. Ominski, B. Boelt

IGC Proceedings (1977-2023)

1. Many factors contribute to changes in the crop-livestock systems, but no logical end-point in the evolution process exists.
2. While benefits of integrated crop-livestock systems over specialised crop and livestock systems are well documented, there has been a move to specialised crop and livestock production.
3. Sustainability issues (manure nutrient concentration, soil quality maintenance, salinity, herbicide resistance, economic instability) have created a renewed interest in integrated crop-livestock systems.
4. Farmer adaptability is as an important link in the evolution between ‘states of integration’.

Overcoming Seasonality Of Production: Opportunities Offered By Forage Conservation Technologies, P. O'Kiely, A. G. Kaiser

IGC Proceedings (1977-2023)

1. Seasonality of forage supply is a key contributor to the seasonality of meat and milk production.
2. Conserving forages as silage or hay can help reduce the seasonality of feed supply.
3. Forage conservation technologies make this contribution mainly through increases in the yield or quality of suitable crops, through an improved efficiency of the conservation process or by allowing a reduction in costs.
4. Future research needs differ considerably among regions of the world.

Strategies To Mitigate Seasonality Of Production In Grassland-Based Systems, Claudio Porqueddu, S. Maltoni, J. G. Mcivor

IGC Proceedings (1977-2023)

1. Fertilisation use and manipulation can cost-effectively alter species composition, increase seasonal herbage production and improve herbage quality.
2. Choice of suitable grassland species, varieties and mixtures offers opportunity to mitigate limitations of seasonal grassland production.
3. Special purpose fodder crops, cereals, shrubs and trees offer alternative or supplementary feed sources.
4. Manipulation of stocking rates, grazing systems, transhumance and pasture management at various times of the season are significant advantageous options.
5. Integration of different strategies is essential to mitigate seasonality in systems of animal production that must be inherently more sustainable over a longer time frame.

Interactions Between Foraging Behaviour Of Herbivores And Grassland Resources In The Eastern Eurasian Steppes, Deli Wang, Guodong Han, Yuguang Bai

IGC Proceedings (1977-2023)

1. In rangeland areas such as the eastern Eurasian steppes (Mongolia and China), foraging behaviour is influenced by plant or vegetation properties with high heterogeneity.
2. Until recently foraging theory has not accounted for the foraging process or ingestive behaviour. Existing theories on foraging behaviour need to evolve and begin to coalesce, and combine with observations or manipulative experiments.
3. Plant and patch properties such as diversity and height influence animal foraging behaviour (related to foraging process or diet selection) in heterogeneous steppes.
4. Stocking rate is the most important management factor for grazing or vegetation management, and determining the optimal stocking rate in …

Foraging Behaviour And Herbage Intake In The Favourable Tropics/Sub-Tropics, S. C. Da Silva, Paulo C. De F. Carvalho

IGC Proceedings (1977-2023)

1. Herbage intake by animals grazing tropical/sub-tropical pastures is directly related to bite mass, as it is for those grazing temperate pastures.
2. Where these swards have low proportions of stem and dead material (controlled swards), herbage intake follows a similar pattern to that of temperate pasture species, but leaf characteristics, such as lamina length play an important role and influence the short-term rate of intake.
3. Sward structural characteristics and behavioural factors are relatively more important than nutritional factors in terms of herbage intake regulation. The feeding value of the herbage produced is potentially adequate to sustain high levels of beef cattle …

Improving The Quality Of Products From Grassland, Nigel D. Scollan, R. J. Dewhurst, A. P. Moloney, J. J. Murphy

IGC Proceedings (1977-2023)

1. Consumers are increasingly aware of the links between diet and health, and place increasing emphasis on nutritional quality as a component of product quality.
2. Meat and milk products are rich sources of nutrients such as omega-3 (n-3) fatty acids and conjugated linoleic acid, which offer health benefits to consumers.
3. Green plants are the primary source of n-3 fatty acids in the food chain.
4. Grassland production systems have the potential to enhance the content of beneficial fatty acids, improve stability (from higher antioxidant content) and alter sensory attributes of meat and milk.
5. Grassland offers considerable scope to help …

Grass And Forage Improvement: Temperate Forages, Chris J. Pollock, M. T. Abberton, M. O. Humphreys

IGC Proceedings (1977-2023)

1. Plant breeding has contributed significantly to the development of effective grassland production systems.
2. New technologies offer enhanced precision in breeding and access to wider genetic variation.
3. The requirement for more sustainable production systems will require genetic improvements in complex traits where the use of new technology will be vital.