Life Sciences Commons^™

Effects Of Ice Encasement During Winter On Different Cultivars Of Phleum Pratense And Lolium Perenne In Norway, M. Jørgensen, Liv Østrem, A. K. Bakken, Mats Höglind

IGC Proceedings (1997-2023)

No abstract provided.

Effect Of Increased Autumn Temperature And Co2 Concentration On Frost Hardening And Winter Survival In Lolium Perenne, Mats Höglind, M. Jørgensen, Liv Østrem, L. Mortensen

IGC Proceedings (1997-2023)

No abstract provided.

Modelling Deficit Irrigation Strategies For Dairy Regions Of Australia, Richard P. Rawnsley, Brendan R. Cullen, Lydia R. Turner, Karen Christie

IGC Proceedings (1997-2023)

No abstract provided.

Growth And Development In Cultivars Of Phleum Pratense And Lolium Perenne During Winter, Liv Østrem, M. Jørgensen, M. Höglind

IGC Proceedings (1997-2023)

No abstract provided.

No3- Uptake And Its Partitioning In Drought Stressed Perennial Ryegrass (Lolium Perenne L.), B. R. Lee, Y. L. Jin, M. Li, W. J. Jung, T. H. Kim

IGC Proceedings (1997-2023)

No abstract provided.

Routes Of Dicyandiamide Uptake In Pasture Plants: A Preliminary Laboratory Study, Pranoy Pal, Andrew M. S. Mcmillan, Surinder Saggar

IGC Proceedings (1997-2023)

A consequence of intensification of New Zealand pastures is increased nitrogen (N) inputs to the soil in the form of urine, dung and mineral fertiliser. Dairy cow urine has a high N content that causes large N losses from the grazed system via nitrate (NO₃^-) leaching, nitrous oxide (N₂O) emissions and ammonia volatilization. Dicyandiamide (DCD) is a nitrification inhibitor that has been proven to reduce NO₃^- leaching and N₂O emissions, and increase pasture in New Zealand pastures (De Klein et al., 2014). DCD was commercially available for use in New …

Development Of A Forage Evaluation System For Perennial Ryegrass Cultivar And Endophyte Combinations In New Zealand Dairy Systems, Jeremy R. Bryant, David F. Chapman, Elizabeth Leonard, William H. Mcmillan, Graham A. Kerr, Glenn Judson, Tim Cookson, Grant R. Edwards

IGC Proceedings (1997-2023)

An economic index for perennial ryegrass (Lolium perenne L.) cultivars is a relatively new concept, although recently introduced in Ireland (McEvoy et al. 2011). By contrast, in dairy cattle breeding, the concept of an economic index rating animals and economic values underlying that index is well entrenched (Philipson et al. 1994; Veerkamp, 1998). Historically, forage evaluation data for individual cultivars were either displayed using absolute numbers for seasonal dry matter production within a season or across all seasons with a notation to indicate statistical differences, or percentage values where a reference cultivar is 100. The adoption of …

Effect Of Nitrogen Fertiliser Applications On Botanical Composition, Lydia R. Turner, Daniel J. Donaghy, Keith G. Pembleton, Richard P. Rawnsley

IGC Proceedings (1997-2023)

The diminishing returns associated with nitrogen (N) fertiliser use over time are well recognised, as are the detrimental effect to the environment of excess N fertiliser use (Eckard 1998). However, many Tasmanian dairy farmers apply continually high rates of N fertiliser (e.g. in excess of 500 kg/ha annually) to minimise risk associated with variable pasture dry matter (DM) yields, and this often occurs at the expense of white clover populations within the pasture (Frame 1990; Frame et al. 1998). The responses of botanical composition and perennial ryegrass DM yields to N fertiliser application rate were investigated in the …

Assessing Resilience Of Pasture Production To Climatic Changes, Brendan R. Cullen, Richard P. Rawnsley, Richard J. Eckard

IGC Proceedings (1997-2023)

Increasing temperatures and atmospheric carbon dioxide (CO₂) concentrations, together with changes to rainfall patterns, will influence seasonal pasture production; however climate change projections for south eastern Australia are uncertain (CSIRO and BoM 2007). Despite this, climate change impact assessments generally rely on specific climate projections, but in this study an alternative approach was developed to test the resilience of production to incremental changes in climate.

Eco-Efficiency Of Forage Production In Northern Germany, Antje Herrmann, Sandra Claus, Christof Kluß, Friedhelm Taube

IGC Proceedings (1997-2023)

A 2-year field experiment was conducted at two sites in Schleswig-Holstein, northern Germany, to quantify and evaluate the carbon footprint of arable forage cropping systems (continuous silage maize, maize-wheat-grass rotation, perennial ryegrass ley) as affected by N fertilizer type and N amount. Total greenhouse gas emission showed a linear increase with N application, with mineral N supply resulting in a higher slope. Product carbon footprint ranged between -66 and 119 kg CO2eq/(GJ NEL) and revealed a quadratic or linear response to fertilizer N input, depending on the cropping system. At N input required for achieving maximum energy yield, perennial ryegrass …

Drivers Of Pasture Growth In Perennial Ryegrass Pastures In Northern New Zealand Dairy Pastures, Natalie R. Mapp, Grant M. Rennie, Warren Mcg. King

IGC Proceedings (1997-2023)

The critical importance of pasture production to New Zealand’s economic performance has been widely recognised. However, a number of critical issues have been identified that limit dairy industry growth, including sub-optimal pasture condition and poor pasture persistence. Dairy farm systems in the Waikato and Bay of Plenty provinces in the upper North Island of New Zealand are predominantly pasture-based, with a temperate climate and they represent around 30% of New Zealand’s total number of dairy farms (LIC and DairyNZ, 2012). This project was established to quantify pasture performance and identify factors that drive that performance. We established a network of …

Economic Values For Perennial Ryegrass Traits In New Zealand Dairy Farm Systems, David F. Chapman, Jeremy R. Bryant, Graham A. Kerr, Glenn Judson, Tim Cookson, Grant R. Edwards, William H. Mcmillan

IGC Proceedings (1997-2023)

Perennial ryegrass (Lolium perenne L.) is the main species used in dairy pastures throughout New Zealand. There are approximately 30 perennial ryegrass cultivars sold commercially in New Zealand, but currently there is no evaluation system which allows farmers to compare the potential impact of different cultivars on the profitability of their farm business. Such an economic evaluation system requires information on performance values (PV) for cultivars which quantifies their performance with respect to the major productivity traits (herbage accumulation (HA, kg DM/ha), nutritive value and persistence) relative to a genetic base, and economic values (EV, Doyle and Elliott 1983) …

Ryegrass Seeding Rate Alters Plant Morphology And Size--Possible Implications For Pasture Persistence, Julia M. Lee, Errol R. Thom, David F. Chapman, Kate T. Wynn, C. Deanne Waugh, Laura Rossi

IGC Proceedings (1997-2023)

Poor persistence of perennial ryegrass (Lolium perenne L.) is a major dairy industry issue in New Zealand and Australia. New ryegrass seed is often drilled at 18-30 kg/ha, although previous research indicated that pastures drilled at 10-12 kg/ha can be just as productive (Frame and Boyd 1986; Praat et al. 1996). High seeding rates increase competition between developing seedlings for light, water and nutrients, reduce plant size (Harris 1990) and potentially survival.

The experiment reported here investigated the effect of plant density (created by differences in seeding rate) on plant morphology and survival. The hypothesis was that plants …

Dry Matter Yield Of Perennial Ryegrass Cultivars Under Mechanical Cutting And Animal Grazing, Patrick A. Cashman, Trevor J. Gilliland, Michael O’Donovan, Marion Beecher, Mary Mcevoy

IGC Proceedings (1997-2023)

Perennial ryegrass evaluation trials are essential to identifying and promoting the most productive cultivars for use at farm level to maximise sward productivity (Grogan and Gilliland 2011). Cultivar testing is predominantly conducted under simulated grazing trials to predict dry matter yield (DMY) performance under animal grazing. Previous studies have shown a high correlation in DMY between these two defoliation methods (Camlin and Stewart 1975; Creighton et al. 2010). In contrast, Binnie and Chestnutt (1991) demonstrated that swards grazed by animals had higher DMY performance than those exposed to simulated grazing managements. Animal pressures such as pulling, treading and nutrient …

Dissecting Drought-Response Strategies Of Perennial Ryegrass (Lolium Perenne L.), Jean-Hugues B. Hatier, Lulu He, Marty J. Faville, Micheal J. Hickey, Chris S. Jones, Mohamed Z. Z. Jahufer, Cory Matthew

IGC Proceedings (1997-2023)

Periodic drought is a severe constraint on the profitability and sustainability of pastoral production. As a result of climate change, drought events are anticipated to increase in frequency and intensity even in regions where annual precipitation is unchanged, as well as where it is reduced.

Many studies have been carried out on drought resistance of forage species (Holloway-Phillips and Brodribb 2011). However, for most experiments, it is unclear which mechanism(s) are responsible for variation in plant performance under moisture stress, whether drought response mechanisms were triggered, or whether differences in performance were simply the result of intrinsic plant vigour. The …