• A comparison of SWAT, HSPF and SHETRAN/GOPC for modelling phosphorus export from three catchments in Ireland

      Nasr, Ahmed Elssidig; Bruen, Michael; Jordan, Philip; Moles, Richard; Kiely, Gerard; Byrne, Paul; Environmental Protection Agency; Teagasc; Teagasc (Elsevier, 02/07/2012)
      Recent extensive water quality surveys in Ireland revealed that diffuse phosphorus (P) pollution originating from agricultural land and transported by runoff and subsurface flows is the primary cause of the deterioration of surface water quality. P transport from land to water can be described by mathematical models that vary in modelling approach, complexity and scale (plot, field and catchment). Here, three mathematical models (SWAT, HSPF and SHETRAN/GOPC) of diffuse P pollution have been tested in three Irish catchments to explore their suitability in Irish conditions for future use in implementing the European Water Framework Directive. After calibrating the models, their daily flows and total phosphorus (TP) exports are compared and assessed. The HSPF model was the best at simulating the mean daily discharge while SWAT gave the best calibration results for daily TP loads. Annual TP exports for the three models and for two empirical models were compared with measured data. No single model is consistently better in estimating the annual TP export for all three catchments.
    • Absence of Curli in Soil-Persistent Escherichia coli Is Mediated by a C-di-GMP Signaling Defect and Suggests Evidence of Biofilm-Independent Niche Specialization

      Somorin, Yinka M; Vollmerhausen, Tara; Waters, Nicholas; Pritchard, Leighton; Abram, Florence; Brennan, Fiona P.; O'Byrne, Conor; Thomas Crawford Hayes Research Award; NUI Galway College of Science (Frontiers, 2018-06-22)
      Escherichia coli is commonly viewed as a gastrointestinal commensal or pathogen although an increasing body of evidence suggests that it can persist in non-host environments as well. Curli are a major component of biofilm in many enteric bacteria including E. coli and are important for adherence to different biotic and abiotic surfaces. In this study we investigated curli production in a unique collection of soil-persistent E. coli isolates and examined the role of curli formation in environmental persistence. Although most soil-persistent E. coli were curli-positive, 10% of isolates were curli-negative (17 out of 170). Curli-producing E. coli (COB583, COB585, and BW25113) displayed significantly more attachment to quartz sand than the curli-negative strains. Long-term soil survival experiments indicated that curli production was not required for long-term survival in live soil (over 110 days), as a curli-negative mutant BW25113ΔcsgB had similar survival compared to wild type BW25113. Mutations in two genes associated with c-di-GMP metabolism, dgcE and pdeR, correlated with loss of curli in eight soil-persistent strains, although this did not significantly impair their survival in soil compared to curli-positive strains. Overall, the data indicate that curli-deficient and biofilm-defective strains, that also have a defect in attachment to quartz sand, are able to reside in soil for long periods of time thus pointing to the possibility that niches may exist in the soil that can support long-term survival independently of biofilm formation.
    • Agricultural nutrient surpluses as potential input sources to grow third generation biomass (microalgae): A review

      Fenton, Owen; O hUallachain, Daire (Elsevier, 2012-05)
      Biofuel consumption is increasing and in order to meet EU targets, alternatives to first and second generation biofuels are being examined. The use of micro-algal biomass in the production of biofuel is an area of research which has received attention in recent years. Traditionally, microalgae are commercially grown using synthetic fertilisers, the price of which is linked with rising oil prices. An alternative to the use of inorganic fertiliser is to use surplus agricultural manures in their raw state, bi-products of anaerobic digestion, or runoff and artificial drainage waters, all of which have variable nutrient contents within and across source types. Many studies showed that manures containing a high nutrient content e.g. pig and poultry manures, or bi-products from anaerobic digestion, are potentially viable sources of nutrients to grow algae. Feasibility issues prevail such as variable nutrient contents amongst and across source types, transparency issues and early and sustained nutrient losses during the storage phase. Agitation and efficient nutrient testing before use are important. In Ireland, pig and poultry manures, dairy dirty water, artificial drainage or runoff waters where coupled with agitation during storage to prevent P precipitation and a CO2 source, all have potential to be used in the future.
    • Agriculture, meteorology and water quality in Ireland: a regional evaluation of pressures and pathways of nutrient loss to water

      Schulte, Rogier P.; Richards, Karl G.; Daly, Karen M.; Kurz, Isabelle; McDonald, E.; Holden, Nicholas M. (Royal Irish Academy, 31/07/2006)
      The main environmental impact of Irish agriculture on surface and ground water quality is the potential transfer of nutrients to water. Soil water dynamics mediate the transport of nutrients to water, and these dynamics in turn depend on agro-meteorological conditions, which show large variations between regions, seasons and years. In this paper we quantify and map the spatio-temporal variability of agro-meteorological factors that control nutrient pressures and pathways of nutrient loss. Subsequently, we evaluate their impact on the water quality of Irish rivers. For nitrogen, pressure and pathways factors coincide in eastern and southern areas, which is reflected in higher nitrate levels of the rivers in these regions. For phosphorus, pathway factors are most pronounced in north-western parts of the country. In south-eastern parts, high pressure factors result in reduced biological water quality. These regional differences require that farm practices be customised to reflect the local risk of nutrient loss to water. Where pathways for phosphorus loss are present almost year-round—as is the case in most of the north-western part of the country—build-up of pressures should be prevented, or ameliorated where already high. In south-eastern areas, spatio-temporal coincidence of nutrient pressures and pathways should be prevented, which poses challenges to grassland management.
    • The Agrodiversity Experiment: three years of data from a multisite study in intensively managed grasslands

      Kirwan, Laura; Connolly, John; Brophy, C.; Baadshaug, Ole; Belanger, Gilles; Black, Alistair D; Camus, Tim; Collins, Rosemary; Cop, Jure; Delgado, Ignacio; et al. (Ecological Society of America, 11/06/2014)
      Intensively managed grasslands are globally prominent ecosystems. We investigated whether experimental increases in plant diversity in intensively managed grassland communities can increase their resource use efficiency. This work consisted of a coordinated, continental-scale 33-site experiment. The core design was 30 plots, representing 15 grassland communities at two seeding densities. The 15 communities were comprised of four monocultures (two grasses and two legumes) and 11 four-species mixtures that varied in the relative abundance of the four species at sowing. There were 1028 plots in the core experiment, with another 572 plots sown for additional treatments. Sites agreed a protocol and employed the same experimental methods with certain plot management factors, such as seeding rates and number of cuts, determined by local practice. The four species used at a site depended on geographical location, but the species were chosen according to four functional traits: a fast-establishing grass, a slow-establishing persistent grass, a fast-establishing legume, and a slow-establishing persistent legume. As the objective was to maximize yield for intensive grassland production, the species chosen were all high-yielding agronomic species. The data set contains species-specific biomass measurements (yield per species and of weeds) for all harvests for up to four years at 33 sites. Samples of harvested vegetation were also analyzed for forage quality at 26 sites. Analyses showed that the yield of the mixtures exceeded that of the average monoculture in >97% of comparisons. Mixture biomass also exceeded that of the best monoculture (transgressive overyielding) at about 60% of sites. There was also a positive relationship between the diversity of the communities and aboveground biomass that was consistent across sites and persisted for three years. Weed invasion in mixtures was very much less than that in monocultures. These data should be of interest to ecologists studying relationships between diversity and ecosystem function and to agronomists interested in sustainable intensification. The large spatial scale of the sites provides opportunity for analyses across spatial (and temporal) scales. The database can also complement existing databases and meta-analyses on biodiversity–ecosystem function relationships in natural communities by focusing on those same relationships within intensively managed agricultural grasslands.
    • Alley coppice—a new system with ancient roots

      Morhart, Christopher D.; Douglas, Gerry C.; Dupraz, Christian; Graves, Anil R.; Nahm, Michael; Paris, Perluigi; Sauter, Udo H.; Sheppard, Jonathan; Spiecker, Heinrich; European Commission (Springer, 2014-05)
      Context: Current production from natural forests will not satisfy future world demand for timber and fuel wood, and new land management options are required. Aims: We explore an innovative production system that combines the production of short rotation coppice in wide alleys with the production of high-value trees on narrow strips of land; it is an alternative form of alley cropping which we propose to call ‘alley coppice’. The aim is to describe this alley coppice system and to illustrate its potential for producing two diverse products, namely high-value timber and energy wood on the same land unit. Methods: Based on a comprehensive literature review, we compare the advantages and disadvantages of the alley coppice system and contrast the features with well-known existing or past systems of biomass and wood production. Results: We describe and discuss the basic aspects of alley coppice, its design and dynamics, the processes of competition and facilitation, issues of ecology, and areas that are open for future research. Conclusion: Based on existing knowledge, a solid foundation for the implementation of alley coppice on suitable land is presented, and the high potential of this system could be shown.
    • Ammonia emissions from cattle dung, urine and urine with dicyandiamide in a temperate grassland

      Fischer, K.; Burchill, William; Lanigan, Gary; Kaupenjohann, M.; Chambers, B. J.; Richards, Karl G.; Forrestal, Patrick J.; Department of Agriculture, Food and the Marine, Ireland (Wiley, 03/09/2015)
      Deposition of urine and dung in pasture-based livestock production systems is a major source of ammonia (NH3) volatilization, contributing to the eutrophication and acidification of water bodies and to indirect nitrous oxide emissions. The objectives of this study were to (i) measure NH3 volatilization from dung and urine in three seasons, (ii) test the effect of spiking urine with the nitrification inhibitor dicyandiamide (DCD) on NH3 volatilization and (iii) generate NH3 emission factors (EFs) for dung, urine and urine + DCD in temperate maritime grassland. Accordingly, simulated dung, urine and urine spiked with DCD (at 30 kg DCD/ha equivalent rate) patches were applied to temperate grassland. Treatments were applied three times in 2014 with one measurement of NH3 loss being completed in spring, summer and autumn. The NH3-N EF was highest in spring, which was most likely due to the near absence of rainfall throughout the duration of loss measurement. The EFs across the experiments ranged between 2.8 and 5.3% (mean 3.9%) for dung, 8.7 and 14.9% (mean 11.2%) for urine and 9.5 and 19.5% (mean 12.9%) for urine + DCD, showing that ammonia loss from dung was significantly lower than from urine. Aggregating country-specific emission data such as those from the current experiment with data from climatically similar regions (perhaps in a weighted manner which accounts for the relative abundance of certain environmental conditions) along with modelling is a potentially resource-efficient approach for refining national ammonia inventories.
    • Ammonia emissions from cattle dung, urine and urine with dicyandiamide in a temperate grassland

      Fischer, K.; Burchill, William; Lanigan, Gary; Kaupenjohann, M.; Chambers, B. J.; Richards, Karl G.; Forrestal, Patrick J.; Department of Agriculture, Food and the Marine, Ireland; RSF13S430; 11S138 (Wiley, 03/09/2015)
      Deposition of urine and dung in pasture-based livestock production systems is a major source of ammonia (NH3) volatilization, contributing to the eutrophication and acidification of water bodies and to indirect nitrous oxide emissions. The objectives of this study were to (i) measure NH3 volatilization from dung and urine in three seasons, (ii) test the effect of spiking urine with the nitrification inhibitor dicyandiamide (DCD) on NH3 volatilization and (iii) generate NH3 emission factors (EFs) for dung, urine and urine + DCD in temperate maritime grassland. Accordingly, simulated dung, urine and urine spiked with DCD (at 30 kg DCD/ha equivalent rate) patches were applied to temperate grassland. Treatments were applied three times in 2014 with one measurement of NH3 loss being completed in spring, summer and autumn. The NH3-N EF was highest in spring, which was most likely due to the near absence of rainfall throughout the duration of loss measurement. The EFs across the experiments ranged between 2.8 and 5.3% (mean 3.9%) for dung, 8.7 and 14.9% (mean 11.2%) for urine and 9.5 and 19.5% (mean 12.9%) for urine + DCD, showing that ammonia loss from dung was significantly lower than from urine. Aggregating country-specific emission data such as those from the current experiment with data from climatically similar regions (perhaps in a weighted manner which accounts for the relative abundance of certain environmental conditions) along with modelling is a potentially resourceefficient approach for refining national ammonia inventories.
    • Ammonia emissions from urea, stabilized urea and calcium ammonium nitrate: insights into loss abatement in temperate grassland

      Forrestal, Patrick J.; Harty, Mary A.; Carolan, Rachael; Lanigan, Gary; Watson, C.J.; Laughlin, Ronald J.; McNeill, Gavin; Chambers, B. J.; Richards, Karl G.; Teagasc Walsh Fellowship Programme; et al. (Wiley, 17/11/2015)
      Fertilizer nitrogen (N) contributes to ammonia (NH3) emissions, which European Union member states have committed to reduce. This study focused on evaluating NH3-N loss from a suite of N fertilizers over multiple applications, and gained insights into the temporal and seasonal patterns of NH3-N loss from urea in Irish temperate grassland using wind tunnels. The fertilizers evaluated were calcium ammonium nitrate (CAN), urea and urea with the N stabilizers N-(n-butyl) thiophosphoric triamide (NBPT), dicyandiamide (DCD), DCD+NBPT and a maleic and itaconic acid polymer (MIP). 200 (and 400 for urea only) kg N/ha/yr was applied in five equal applications over the growing season at two grassland sites (one for MIP). Mean NH3-N losses from CAN were 85% lower than urea and had highly variable loss (range 45% points). The effect of DCD on NH3 emissions was variable. MIP did not decrease NH3-N loss, but NBPT caused a 78.5% reduction and, when combined with DCD, a 74% reduction compared with urea alone. Mean spring and summer losses from urea were similar, although spring losses were more variable with both the lowest and highest losses. Maximum NH3-N loss usually occurred on the second day after application. These data highlight the potential of stabilized urea to alter urea NH3-N loss outcomes in temperate grassland, the need for caution when using season as a loss risk guide and that urea hydrolysis in temperate grassland initiates quickly. Micrometeorological measurements focused specifically on urea are needed to determine absolute NH3-N loss levels in Irish temperate grassland.
    • Ammonia emissions from urea, stabilized urea and calcium ammonium nitrate: insights into loss abatement in temperate grassland

      Forrestal, Patrick J.; Harty, Mary A.; Carolan, Rachael; Lanigan, Gary; Watson, C.J.; Laughlin, Ronald J.; McNeill, Gavin; Chambers, B. J.; Richards, Karl G.; Department of Agriculture, Food and the Marine, Ireland; et al. (Wiley, 17/11/2015)
      Fertilizer nitrogen (N) contributes to ammonia (NH3) emissions, which European Union member states have committed to reduce. This study focused on evaluating NH3-N loss from a suite of N fertilizers over multiple applications, and gained insights into the temporal and seasonal patterns of NH3-N loss from urea in Irish temperate grassland using wind tunnels. The fertilizers evaluated were calcium ammonium nitrate (CAN), urea and urea with the N stabilizers N-(n-butyl) thiophosphoric triamide (NBPT), dicyandiamide (DCD), DCD+NBPT and a maleic and itaconic acid polymer (MIP). 200 (and 400 for urea only) kg N/ha/yr was applied in five equal applications over the growing season at two grassland sites (one for MIP). Mean NH3-N losses from CAN were 85% lower than urea and had highly variable loss (range 45% points). The effect of DCD on NH3 emissions was variable. MIP did not decrease NH3-N loss, but NBPT caused a 78.5% reduction and, when combined with DCD, a 74% reduction compared with urea alone. Mean spring and summer losses from urea were similar, although spring losses were more variable with both the lowest and highest losses. Maximum NH3-N loss usually occurred on the second day after application. These data highlight the potential of stabilized urea to alter urea NH3-N loss outcomes in temperate grassland, the need for caution when using season as a loss risk guide and that urea hydrolysis in temperate grassland initiates quickly. Micrometeorological measurements focused specifically on urea are needed to determine absolute NH3-N loss levels in Irish temperate grassland.
    • Application of Dexter’s soil physical quality index: an Irish case study

      Fenton, Owen; Vero, Sara; Schulte, Rogier P. O.; O'Sullivan, Lilian; Bondi, G.; Creamer, Rachel E.; Department of Agriculture, Food and the Marine, Ireland; 6582 (Teagasc (Agriculture and Food Development Authority), Ireland, 26/08/2017)
      Historically, due to a lack of measured soil physical data, the quality of Irish soils was relatively unknown. Herein, we investigate the physical quality of the national representative profiles of Co. Waterford. To do this, the soil physical quality (SPQ) S-Index, as described by Dexter (2004a,b,c) using the S-theory (which seeks the inflection point of a soil water retention curve [SWRC]), is used. This can be determined using simple (S-Indirect) or complex (S-Direct) soil physical data streams. Both are achievable using existing data for the County Waterford profiles, but until now, the suitability of this S-Index for Irish soils has never been tested. Indirect-S provides a generic characterisation of SPQ for a particular soil horizon, using simplified and modelled information (e.g. texture and SWRC derived from pedo-transfer functions), whereas Direct-S provides more complex site-specific information (e.g. texture and SWRC measured in the laboratory), which relates to properties measured for that exact soil horizon. Results showed a significant correlation between S-Indirect (Si) and S-Direct (Sd). Therefore, the S-Index can be used in Irish soils and presents opportunities for the use of Si at the national scale. Outlier horizons contained >6% organic carbon (OC) and bulk density (Bd) values <1 g/cm3 and were not suitable for Si estimation. In addition, the S-Index did not perform well on excessively drained soils. Overall correlations of Si. with Bd and of Si. with OC% for the dataset were detected. Future work should extend this approach to the national scale dataset in the Irish Soil Information System.
    • Ash dieback in Ireland – A review of European management options and case studies in remedial silviculture

      Short, Ian; Hawe, Jerry; Woodland Trust NI; COFORD; Teagasc (Society of Irish Foresters, 2018)
      Ash dieback, caused by Hymenoscyphus fraxineus, is developing rapidly across the island of Ireland. Ireland’s ash (Fraxinus excelsior L.) woodlands, particularly first rotation plantations, are quite unique and are at particular risk of very rapid decline. Urgent action is required in order to minimise the economic, ecological and social impact of the disease. However, for this to happen forest owners require guidance regarding potential positive management interventions. This article outlines the wider, mainly European, experience of remedial silviculture. It presents three case studies on existing remedial silviculture trials in Ireland. In the absence of silvicultural research data specific to the evolving situation with ash dieback, this article explores the potential benefits of positive practical actions which may minimise the impact of the disease. Despite the seriousness of the situation, such silvicultural activity may even result in a positive economic outcome. It is hoped that by beginning to document potential mitigatory management options, this paper may bring some reassurance to owners and managers of ashdominated woodlands.
    • Ash dieback on the island of Ireland

      McCracken, A.R.; Douglas, Gerry C.; Ryan, C.; Destefanis, M.; Cooke, L.R.; European Co-Operation in Science and Technology (Swedish University of Agricultural Sciences, 2017)
      On the island of Ireland it is estimated that there are over half a million kilometres of hedgerows (400,000+ km in the Republic of Ireland (Rep. Ireland) and 113,000+ in Northern Ireland (Northern Ireland). Ash (Fraxinus excelsior) is the second most important component, after hawthorn (Crataegus monogyna), in large proportions of this hedgerow network. In the Rep. Ireland over 20,000 ha of ash have been planted since 1990, primarily for sawlogs and to provide material for the manufacture of hurleys, which are used in an important national sport called hurling, and for camogie sticks used to play camogie. Ash dieback, caused by Hymenoscyphus fraxineus, was first identified on the island in October 2012 and since then has been detected at 306 sites (195 in Rep. Ireland and 111 in Northern Ireland). In the vast majority of cases the outbreaks have been on young, imported trees planted within the previous 5 – 6 years and it was evident that the pathogen had been introduced on trees for planting. On a small number of occasions there was evidence of the pathogen cycling within a plantation or moving from the plantation to infect neighbouring hedgerow trees. One possible mechanism by which the pathogen can build up sufficient inoculum is by the formation of apothecia on infected woody tissue high up on the plants. Rep. Ireland and Northern Ireland have strict policies of eradication and containment, as set out in the All-Ireland Chalara Control Strategy. To date over 2.1 million trees have been destroyed as part of an eradication strategy. It is considered that this prompt and far-reaching action has had a significant impact, significantly mitigating and preventing the rapid establishment of the pathogen and limiting its spread. The interventions since the disease was first confirmed have helped to protect the considerable investment in ash plantations of the last 20 years. The pathogen has not, however, been eradicated from the island of Ireland and it remains to be seen how widespread, and how quickly ash dieback will become established on the island of Ireland. The latest figures from the Republic of Ireland are that 733 hectares of ash plantation has been reconstituted with another species as a result of Chalara and this has cost our state €2.6 million so far; in addition, Chalara has been found and confirmed in all 26 counties of the Republic of Ireland to a greater or lesser extent. As a result the current policies and procedures regarding Chalara are under review.
    • Assessing populations of the major cereal pathogens for reduced sensitivity to MBC, DMI and Strobilurin fungicides

      O’Sullivan, Eugene (Teagasc, 01/08/2009)
      Studies of eyespot populations in winter wheat crops in the period 2001 to 2003 showed that the R type (Tapesia acuformis) is the dominant strain comprising 77% of isolates. Over 90% of isolates were resistant to MBC fungicides, 53% showed reduced sensitivity to prochloraz and 22% reduced sensitivity to cyprodinil. A study of winter wheat crops in February and March 2003 showed that resistance to strobilurin fungicides was widespread in Mycosphaerella graminicola (Septoria tritici) populations. Resistance was found in all but one of 21 crops sampled, at levels ranging from 9% to 84% with an average of 48%. Subsequent studies of 27 crops over the summer of 2003 showed that strobilunin resistance increased from an average of 31% before the application of the second (T2) spray to an average of 73%, three to four weeks after the application of the final (T3) spray. Strobilurin resistance in M. graminicola remained high in 2004, ranging from 50% to 100% with an average of 83% in populations in winter wheat crops sampled in March. The effect of different fungicide programmes on resistance was studied during summer 2003 at two experimental sites. Levels of strobilurin resistance in M. graminicola populations increased during the summer, in unsprayed plots and plots treated with triazole fungicides as well as in those treated with strobiurin fungicides at both sites. M. graminicola populations in winter wheat crops sampled in 2003 and 2004 were predominantly resistant to MBC-generating fungicides and sensitive to the triazole-based fungicides. Studies of the barley leaf blotch pathogen Rhynchosporium secalis showed that resistance to MBC fungicides occurred in 20% of isolates collected from crops from 2001 to 2003, but all isolates were sensitive to triazole and strobilurin fungicides.
    • Assessing the Impact of Pollen-mediated Gene Flow from GM Herbicide Tolerant Brassica Napus into Common Wild Relatives in Ireland

      Collier, Marcus J.; Mullins, Ewen; Environmental Protection Agency; Teagasc; ERTDI 2006-B-MS-46; 2007-B-DS-1-S1 (Royal Irish Academy, 30/04/2012)
      Although now we have had many years of research completed on assessing the potential environmental impact of GM crops, concern remains over their potential impact on biodiversity in the rural landscape. In particular, issues have arisen in regards to the modification of crops with traits that could introgress into sexually compatible wild relatives. In contrast to wheat, barley, potato and maize, Brassica napus (oilseed rape) is the only commercial crop grown in Ireland at present with the potential to successfully transfer its DNA, via pollen-mediated gene flow, into inter-related weed species. This review details the species in question and by examining the relevant literature that relates to Irish agronomic conditions, demonstrates that gene flow is likely to occur, especially to an earlier used cultivar, Brassica rapa. However, the critical factor remains not that GM traits will flow from the commercial source but what might the consequences of said gene flow events be. This review indicates that the conferred trait in question (in this case, herbicide tolerance) can only impact on weed diversity in the presence of selecting herbicide action. In the absence of the herbicide, the GM traits will be lost from the wild species over time and will not confer any selective advantage that could facilitate population growth.
    • Assessment of water-limited winter wheat yield potential at spatially contrasting sites in Ireland using a simple growth and development model

      Lynch, J.P.; Fealy, Reamonn; Doyle, D.; Black, L.; Spink, John; Department of Agriculture, Food and the Marine, Ireland (Teagasc (Agriculture and Food Development Authority), Ireland, 19/09/2017)
      Although Irish winter wheat yields are among the highest globally, increases in the profitability of this crop are required to maintain its economic viability. However, in order to determine if efforts to further increase Irish wheat yields are likely to be successful, an accurate estimation of the yield potential is required for different regions within Ireland. A winter wheat yield potential model (WWYPM) was developed, which estimates the maximum water-limited yield achievable, within the confines of current genetic resources and technologies, using parameters for winter wheat growth and development observed recently in Ireland and a minor amount of daily meteorological input (maximum and minimum daily temperature, total daily rainfall and total daily incident radiation). The WWYPM is composed of three processes: (i) an estimation of potential green area index, (ii) an estimation of light interception and biomass accumulation and (iii) an estimation of biomass partitioning to grain yield. Model validation indicated that WWYPM estimations of water-limited yield potential (YPw) were significantly related to maximum yields recorded in variety evaluation trials as well as regional average and maximum farm yields, reflecting the model’s sensitivity to alterations in the climatic environment with spatial and seasonal variations. Simulations of YPw for long-term average weather data at 12 sites located at spatially contrasting regions of Ireland indicated that the typical YPw varied between 15.6 and 17.9 t/ha, with a mean of 16.7 t/ha at 15% moisture content. These results indicate that the majority of sites in Ireland have the potential to grow high-yielding crops of winter wheat when the effects of very high rainfall and other stresses such as disease incidence and nutrient deficits are not considered.
    • Atypical Listeria innocua strains possess an intact LIPI-3

      Clayton, Evelyn M; Daly, Karen M.; Guinane, Caitriona M.; Hill, Colin; Cotter, Paul D.; Ross, R Paul; Enterprise Ireland; Science Foundation Ireland; 06/IN.1/B98; 10/IN.1/B3027 (Biomed Central, 08/03/2014)
      Background: Listeria monocytogenes is a food-borne pathogen which is the causative agent of listeriosis and can be divided into three evolutionary lineages I, II and III. While all strains possess the well established virulence factors associated with the Listeria pathogenicity island I (LIPI-1), lineage I strains also possess an additional pathogenicity island designated LIPI-3 which encodes listeriolysin S (LLS), a post-translationally modified cytolytic peptide. Up until now, this pathogenicity island has been identified exclusively in a subset of lineage I isolates of the pathogen Listeria monocytogenes. Results: In total 64 L. innocua strains were screened for the presence of LIPI-3. Here we report the identification of an intact LIPI-3 in 11 isolates of L. innocua and the remnants of the cluster in several others. Significantly, we can reveal that placing the L. innocua lls genes under the control of a constitutive promoter results in a haemolytic phenotype, confirming that the cluster is capable of encoding a functional haemolysin. Conclusions: Although the presence of the LIPI-3 gene cluster is confined to lineage I isolates of L. monocytogenes, a corresponding gene cluster or its remnants have been identified in many L. innocua strains.
    • Beef production from feedstuffs conserved using new technologies to reduce negative environmental impacts

      O’Kiely, Padraig; Crosson, Paul; Hamilton, William J.; Little, Enda; Stacey, Pamela; Walsh, Karl; Black, Alistair D; Crowley, James C.; Drennan, Michael J; Forristal, Dermot; et al. (Teagasc, 2007-12-01)
      Most (ca. 86%) Irish farms make some silage. Besides directly providing feed for livestock, the provision of grass silage within integrated grassland systems makes an important positive contribution to effective grazing management and improved forage utilisation by grazing animals, and to effective feed budgeting by farmers. It can also contribute to maintaining the content of desirable species in pastures, and to livestock not succumbing to parasites at sensitive times of the year. Furthermore, the optimal recycling of nutrients collected from housed livestock can often be best achieved by spreading the manures on the land used for producing the conserved feed. On most Irish farms, grass silage will remain the main conserved forage for feeding to livestock during winter for the foreseeable future. However, on some farms high yields of whole-crop (i.e. grain + straw) cereals such as wheat, barley and triticale, and of forage maize, will be an alternative option provided that losses during harvesting, storage and feedout are minimised and that input costs are restrained. These alternative forages have the potential to reliably support high levels of animal performance while avoiding the production of effluent. Their production and use however will need to advantageously integrate into ruminant production systems. A range of technologies can be employed for crop production and conservation, and for beef production, and the optimal options need to be identified. Beef cattle being finished indoors are offered concentrate feedstuffs at rates that range from modest inputs through to ad libitum access. Such concentrates frequently contain high levels of cereals such as barley or wheat. These cereals are generally between 14% to 18% moisture content and tend to be rolled shortly before being included in coarse rations or are more finely processed prior to pelleting. Farmers thinking of using ‘high-moisture grain’ techniques for preserving and processing cereal grains destined for feeding to beef cattle need to know how the yield, conservation efficiency and feeding value of such grains compares with grains conserved using more conventional techniques. European Union policy strongly encourages a sustainable and multifunctional agriculture. Therefore, in addition to providing European consumers with quality food produced within approved systems, agriculture must also contribute positively to the conservation of natural resources and the upkeep of the rural landscape. Plastics are widely used in agriculture and their post-use fate on farms must not harm the environment - they must be managed to support the enduring sustainability of farming systems. There is an absence of information on the efficacy of some new options for covering and sealing silage with plastic sheeting and tyres, and an absence of an inventory of the use, re-use and post-use fate of plastic film on farms. Irish cattle farmers operate a large number of beef production systems, half of which use dairy bred calves. In the current, continuously changing production and market conditions, new beef systems must be considered. A computer package is required that will allow the rapid, repeatable simulation and assessment of alternate beef production systems using appropriate, standardised procedures. There is thus a need to construct, evaluate and utilise computer models of components of beef production systems and to develop mathematical relationships to link system components into a network that would support their integration into an optimal system model. This will provide a framework to integrate physical and financial on-farm conditions with models for estimating feed supply and animal growth patterns. Cash flow and profit/loss results will be developed. This will help identify optimal systems, indicate the cause of failure of imperfect systems and identify areas where applied research data are currently lacking, or more basic research is required.
    • Botanical rejuvenation of field margins and benefits for invertebrate fauna on a drystock farm in County Longford

      Sheridan, H.; Finn, John A.; O'Donovan, G.; Teagasc Walsh Fellowship Programme (Royal Irish Academy, 30/07/2009)
      This study investigates methods to rejuvenate the fl ora of previously degraded fi eld margins on a pastoral farm in County Longford. We also assess the effects of individual treatments on the abundance of various orders of invertebrates recorded within the experimental plots. Field margin treatments were 1.5m-wide unfenced control margins, 1.5m-wide fenced margins or 3.5m-wide fenced margins. Nutrient inputs were excluded from all of the experimental plots. The botanical composition of the plots was examined on four occasions between 2002 and 2004 using permanent, nested quadrats. Emergence traps were used to measure invertebrate abundance within treatment plots and the main sward. Results indicated that 1) exclusion of nutrient inputs had a positive effect on plant species richness within the fi eld margins; 2) plant species richness decreased with increased distance from the hedgerow; 3) herb species richness was greatest in the 1.5m closest to the hedgerow; 4) greater abundance of invertebrates occurred within the 3.5m-wide margins; 5) successful control of Pteridium aquilinum was achieved through spot treatment with the selective herbicide ‘Asulox’; and 6) a combination of management techniques such as cutting and grazing is likely to enhance plant species richness and facilitate the structural diversity of vegetation that is necessary for many invertebrate taxa.
    • Broadleaf thinning in Ireland - a review of European silvicultural best practice

      Hawe, Jerry; Short, Ian; Department of Agriculture, Food and the Marine, Ireland (Society of Irish Foresters, 2016)
      A substantial first-rotation broadleaf plantation resource in Ireland is progressively entering a thinning phase. Silvicultural best practice in support of such a management intervention needs to be developed for this new woodland resource to achieve its maximum commercial potential. National research trials are key to the provision of information for the development of best practice. Determining the current state-of-the-art is a prerequisite to the design and implementation of appropriate research trials. This study reviews the literature concerning the fundamental principles of broadleaf thinning with particular regard to timing, intensity and impacts on crop tree growth response, focussing on a range of commonly planted broadleaf species in Ireland. The overall aim of this review is to gain a fuller understanding of the most effective thinning methodology to be employed to maximise the production of high quality hardwood timber. In doing so it is intended that the information presented may support ongoing and future research trials with regard to potential silvicultural treatments to apply, data types and analysis and the likely results of practical application to commercial forestry.