Development of a system to rank perennial ryegrass cultivars according to their economic value to dairy farm businesses in south-eastern Australia

2018 ◽  
Vol 58 (8) ◽  
pp. 1552 ◽  
Author(s):  
C. M. Leddin ◽  
J. L. Jacobs ◽  
K. F. Smith ◽  
K. Giri ◽  
B. Malcolm ◽  
...  
Keyword(s):  
Perennial Ryegrass ◽  
Mixed Model ◽  
Linear Mixed Model ◽  
Economic Value ◽  
Dairy Farm ◽  
Grass Species ◽  
South Eastern ◽  
Eastern Australia ◽  
Forage Value ◽  
South Eastern Australia

Dairy production systems in south-eastern Australia are based primarily on grazed pasture. Perennial ryegrass (Lolium perenne L.) is the major grass species used in this region and farmers are faced with the challenge of choosing from more than 60 commercially available cultivars. This paper describes the development of a system termed as a forage value index that ranks the overall performance of perennial ryegrass cultivars relative to cultivar Victorian according to the summation of the estimated difference in the value of seasonal dry-matter (DM) yield of the cultivars. Average predicted seasonal DM yields were calculated by analysing the results of eight available perennial ryegrass plot trials across south-eastern Australia, using a multi-environment, multi-harvest linear mixed model. The differences in the model-predicted DM yield of each cultivar was compared with cultivar Victorian in each of five seasonal periods (autumn, winter, early spring, late spring, summer) to generate a series of performance values (1 per period) for each cultivar. Each performance value was then multiplied by an economic value (AU$/kg extra pasture grown) relating to each of four regions (Gippsland, northern Victoria, south-western Victoria, Tasmania) and seasonal period and aggregated to generate an overall forage value index rating for each cultivar. Economic values ranged from AU$0.11 to AU$0.39 per extra kilogram of DM grown, depending on the season and region, which translated into estimated benefits on dairy farms of up to AU$183 per ha per year for farmers that use high-yielding cultivars in place of cultivar Victorian perennial ryegrass.

scholarly journals Variation in the Nutritive Characteristics of Modern Perennial Ryegrass Cultivars in South-Eastern Australian Dairy Environments and Prospects for Inclusion in the Australian Forage Value Index (FVI)

Agronomy ◽  
2022 ◽  
Vol 12 (1) ◽  
pp. 136
Author(s):  
Clare Leddin ◽  
Khageswor Giri ◽  
Kevin Smith
Keyword(s):  
Functional Groups ◽  
Perennial Ryegrass ◽  
Nutritive Value ◽  
Dairy Farm ◽  
Breeding Programs ◽  
South Eastern ◽  
Individual Trait ◽  
Eastern Australia ◽  
Forage Value ◽  
South Eastern Australia

Perennial ryegrass (PRG) is an important forage grown on dairy farms in temperate regions globally, including south-eastern Australia. A forage value index (FVI) providing information on the seasonal production of commercially available PRG cultivars is currently available. Despite the importance of the nutritive value of pasture in dairy farm systems, the nutritive characteristics of PRG cultivars are not currently included in the FVI as they are not routinely measured in cultivar evaluation trials. This study investigated differences between cultivar functional groups (diploid and tetraploid). It also examined differences between individual cultivars within seasons at four locations in south-eastern Australia and examined how trial location affects cultivar ranking. Samples were collected from existing cultivar evaluation trials over a 3-year period and analysed for nutritive characteristics. There were differences (p < 0.05) between diploids and tetraploids for metabolisable energy (ME) and neutral detergent fibre (NDF) in each season at each location with a few exceptions in summer and autumn. Crude protein (CP) differed between functional groups in some seasons at some sites. Spearman rank correlations within season were strong for ME between trial locations (r = 0.78–0.96), moderate to high for NDF (0.51–0.86) and variable for CP (−0.69–0.56). These findings provide guidance on methods for implementing nutritive value testing in cultivar evaluation trials and support the imminent inclusion of ME in the Australian FVI. The ranking of cultivars for ME was more consistent across trial sites compared to NDF and CP, suggesting the latter two traits, in particular CP, are more sensitive to environmental influences. Based on these results, we do not recommend the inclusion of CP as an individual trait in the Australian FVI. A significantly larger dataset and further research on the genotype by environment interactions would be needed to reconsider this. The addition of ME in the Australian FVI will lead to better cultivar choices by farmers and could lead to more targeted perennial ryegrass breeding programs.

scholarly journals Effect of Herbage Density, Height and Age on Nutrient and Invertebrate Generalist Predator Abundance in Permanent and Temporary Pastures

Land ◽  
2020 ◽  
Vol 9 (5) ◽  
pp. 164
Author(s):  
Rémi Toupet ◽  
Alastair T. Gibbons ◽  
Sara L. Goodacre ◽  
Matt J. Bell
Keyword(s):  
Perennial Ryegrass ◽  
Crude Protein ◽  
Dry Matter ◽  
Mixed Model ◽  
Linear Mixed Model ◽  
Grass Species ◽  
Nutrient Concentrations ◽  
Generalist Predator ◽  
Diverse Range ◽  
Predator Abundance

The aim of this research was to assess differences in the quantity and quality of herbage and invertebrate generalist predator abundance among permanent and temporary pastures. Two permanent pastures and four temporary ley pastures (either one year or two years since being sown) were monitored weekly for 10 weeks in the spring. Permanent pastures included a diverse range of native UK grass species, and temporary ley pastures were predominantly perennial ryegrass (Lolium perenne) with or without white clover (Trifolium repens). Weekly measurements of herbage height (in centimeters), herbage cover (fresh and dry matter in kg per hectare) and herbage density (fresh and dry matter in kg per hectare per centimeter) were obtained for each field, along with lycosid spider and carabid beetle abundance. Weekly pasture samples were used to obtain nutrient concentrations of dry matter, crude protein, neutral detergent fibre (NDF), acid detergent fibre (ADF), ash, oil, sugars, digestible organic matter in the dry matter (DOMD) and metabolisable energy (ME) in the herbage as a measure of forage quality for grazing or harvesting. A linear mixed model was used to assess the effect of sward age, herbage density and height on herbage production, nutrient concentrations and invertebrate abundance. Although this study showed that permanent pastures were associated with lower nutrient concentrations of crude protein, ash, oil and ME compared to younger and predominantly perennial ryegrass pastures, the older pastures were associated with higher carabid numbers. Furthermore, permanent pastures had a higher density of dry matter herbage compared to younger pastures, and more dense and taller swards were associated with higher lycosid numbers. The study suggests that within pastures of 3 to 20 cm height, increasing the height and density of swards increases both ME and oil concentrations in herbage, therefore enhancing forage nutrient quality. Older and more permanent pastures can be beneficial for plant and invertebrate generalist predator populations, and still provide a useful source of nutrients for forage production.

scholarly journals Phosphorus fertiliser management for pastures based on native grasses in south-eastern Australia

2019 ◽  
Vol 70 (12) ◽  
pp. 1044
Author(s):  
M. L. Mitchell ◽  
M. R. McCaskill ◽  
R. D. Armstrong
Keyword(s):  
Low Fertility ◽  
Grass Species ◽  
Soil Test ◽  
Native Grasses ◽  
Native Grass ◽  
Themeda Triandra ◽  
South Eastern ◽  
Eastern Australia ◽  
Native Pasture ◽  
South Eastern Australia

Approximately 3.1 Mha (22%) of the agricultural area of south-eastern Australia can be classified as native pasture. There is the assumption that, owing to the widespread occurrence of low-fertility soils in Australia, native grass species do not respond to increased phosphorus (P) fertility. Currently, there are no industry recommendations of target soil-test P values for native-grass-based pastures. This paper reviews the responses of perennial native pasture species endemic to south-eastern Australia to P application in controlled environments, surveys, replicated experiments and paired-paddock trials. Eighty-seven site-years of trial data where different levels of P were applied, conducted over the last two decades, on native-based pastures in south-eastern Australia are reviewed. Data indicate that application of P fertilisers to native grass pastures can increase dry matter (DM) production and maintain pasture stability. However, minimum targets for herbage mass (800 kg DM/ha) and groundcover (80%) are required to ensure persistence of perennial native grasses. Stocking rates also need to match carrying capacity of the pasture. Based on previous research, we recommend target soil-test (Olsen; 0–10 cm) P levels for fertility-tolerant native grass pastures, based on Microlaena stipoides, Rytidosperma caespitosum, R. fulvum, R. richardsonii, R. duttonianum and R. racemosum, of 10–13 mg/kg, whereas for pastures based on fertility-intolerant species such as Themeda triandra, lower levels of &lt;6 mg/kg are required to ensure botanical stability.

Modelling and prediction of dry matter yield of perennial ryegrass cultivars sown in multi-environment multi-harvest trials in south-eastern Australia

2019 ◽  
Vol 243 ◽  
pp. 107614 ◽  
Author(s):  
Khageswor Giri ◽  
Kohleth Chia ◽  
Subhash Chandra ◽  
Kevin F. Smith ◽  
Clare M. Leddin ◽  
...  
Keyword(s):  
Perennial Ryegrass ◽  
Dry Matter ◽  
Dry Matter Yield ◽  
South Eastern ◽  
Eastern Australia ◽  
South Eastern Australia

Persistence and productivity of perennial ryegrass in sheep pastures in south-western Victoria: a review

2001 ◽  
Vol 41 (1) ◽  
pp. 117 ◽  
Author(s):  
R. A. Waller ◽  
P. W. G. Sale
Keyword(s):  
Perennial Ryegrass ◽  
Seedling Recruitment ◽  
Climatic Conditions ◽  
Grazing Management ◽  
Annual Rainfall ◽  
Nitrogen And Phosphorus ◽  
Dormant State ◽  
South Eastern ◽  
Eastern Australia ◽  
South Eastern Australia

Loss of perennial ryegrass (Lolium perenne L.) from the pasture within several years of sowing is a common problem in the higher rainfall (550–750 mm annual rainfall), summer-dry regions of south-eastern Australia. This pasture grass came to Australia from northern Europe, where it mostly grows from spring to autumn under mild climatic conditions. In contrast, the summers are generally much drier and hotter in this region of south-eastern Australia. This ‘mismatch’ between genotype and environment may be the fundamental reason for the poor persistence. There is hope that the recently released cultivars, Fitzroy and Avalon, selected and developed from naturalised ryegrass pastures in south-eastern Australia for improved winter growth and persistence will improve the performance of perennial ryegrass in the region. Soon-to-be released cultivars, developed from Mediterranean germplasm, may also bridge the climatic gap between where perennial ryegrass originated and where it is grown in south-eastern Australia. Other factors that influence perennial ryegrass persistence and productivity can be managed to some extent by the landholder. Nutrient status of the soil is important since perennial ryegrass performance improves relative to many other pasture species with increasing nitrogen and phosphorus supply. It appears that high soil exchangeable aluminium levels are also reducing ryegrass performance in parts of the region. The use of lime may resolve problems with high aluminium levels. Weeds that compete with perennial ryegrass become prevalent where bare patches occur in the pasture; they have the opportunity to invade pastures at the opening rains each year. Maintaining some herbage cover over summer and autumn should reduce weed establishment. Diseases of ryegrass are best managed by using resistant cultivars. Insect pests may be best managed by understanding and monitoring their biology to ensure timely application of pesticides and by manipulating herbage mass to alter feed sources and habitat. Grazing management has potential to improve perennial ryegrass performance as frequency and intensity of defoliation affect dry matter production and have been linked to ryegrass persistence, particularly under moisture deficit and high temperature stress. There is some disagreement as to the merit of rotational stocking with sheep, since the results of grazing experiments vary markedly depending on the rotational strategy used, climate, timing of the opening rains, stock class and supplementary feeding policy. We conclude that flexibility of grazing management strategies is important. These strategies should be able to be varied during the year depending on climatic conditions, herbage mass, and plant physiology and stock requirements. Two grazing strategies that show potential are a short rest from grazing the pasture at the opening rains until the pasture has gained some leaf area, in years when the opening rains are late. The second strategy is to allow ryegrass to flower late in the season, preventing new vegetative growth, and perhaps allowing for tiller buds to be preserved in a dormant state over the summer. An extension of this strategy would be to delay grazing until after the ryegrass seed heads have matured and seed has shed from the inflorescences. This has the potential to increase ryegrass density in the following growing season from seedling recruitment. A number of research opportunities have been identified from this review for improving ryegrass persistence. One area would be to investigate the potential for using grazing management to allow late development of ryegrass seed heads to preserve tiller buds in a dormant state over the summer. Another option is to investigate the potential, and subsequently develop grazing procedures, to allow seed maturation and recruitment of ryegrass seedlings after the autumn rains.

Phosphorus export at the paddock, farm-section, and whole farm scale on an irrigated dairy farm in south-eastern Australia

2005 ◽  
Vol 56 (1) ◽  
pp. 1 ◽  
Author(s):  
K. Barlow ◽  
D. Nash ◽  
R. B. Grayson
Keyword(s):  
Surface Runoff ◽  
Water Reuse ◽  
Agricultural Land ◽  
Dairy Farm ◽  
South Eastern ◽  
Eastern Australia ◽  
Farm Scale ◽  
Phosphorus Export ◽  
South Eastern Australia

Phosphorus (P) exported from agricultural land contributes to the eutrophication of inland water systems. Although P export has been extensively researched at the paddock scale, our understanding of farm-scale export is limited. This paper presents the results of a 3-year monitoring project that investigated P export at the paddock, farm-section, and whole farm scales on an irrigated dairy farm in south-eastern Australia. Annual average concentrations of 2.2–11 mg P/L, and annual loads of 2.5–23 kg P/ha were measured at the paddock and farm-section scale over the 3 years, with the quality of irrigation water applied having no significant effect on P export in surface runoff. At the farm scale, effective management of the water reuse system significantly reduced phosphorus export by up to 98%. During the 3-year period, P concentrations and loads exported in surface runoff consistently decreased between the paddock and farm-section scales (e.g. P-28 exported 13.8 kg P/ha, whereas S-4 exported 6.7 kg/ha in 2001), with the decrease in P export described using a scaling factor. Our results suggest that data on paddock-scale P export can rarely be proportionally assigned to predict section- or farm-scale export, at least on irrigated dairy farms in south-eastern Australia.

Sign in / Sign up

Export Citation Format

Share Document