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Australian farmers and scientists have embraced the use of new pasture legume species more than those in any other country, with 36 annual and 11 perennial legumes having cultivars registered for use. Lucerne (Medicago sativa), white clover (Trifolium repens), and red clover (T. pratense) were introduced by the early European settlers and are still important species in Australia, but several other species, notably annual legumes, have been developed specifically for Australian environments, leading to the evolution of unique farming systems. Subterranean clover (T. subterraneum) and annual medics (Medicago spp.) have been the most successful species, while a suite of new annual legumes, including serradellas (Ornithopus compressus and O. sativus), biserrula (Biserrula pelecinus) and other Trifolium and Medicago species, has expanded the range of legume options. Strawberry clover (T. fragiferum) was the first non-traditional, perennial legume commercialised in Australia. Other new perennial legumes have recently been developed to overcome the soil acidity and waterlogging productivity constraints of lucerne and white clover and to reduce groundwater recharge and the spread of dryland salinity. These include birdsfoot trefoil (Lotus corniculatus), Talish clover (T. tumens), and hairy canary clover (Dorycnium hirsutum). Stoloniferous red clover cultivars and sulla (Hedysarum coronarium) cultivars adapted to southern Australia have also been released, along with a new cultivar of Caucasian clover (T. ambiguum) aimed at overcoming seed production issues of cultivars released in the 1970s. New species under development include the annual legume messina (Melilotus siculus) and the perennial legume narrowleaf lotus (L. tenuis) for saline, waterlogged soils, and the drought-tolerant perennial legume tedera (Bituminaria bituminosa var. albomarginata). Traits required in future pasture legumes include greater resilience to declining rainfall and more variable seasons, higher tolerance of soil acidity, higher phosphorous utilisation efficiency, lower potential to produce methane emissions in grazing ruminants, better integration into weed management strategies on mixed farms, and resistance to new pest and disease threats. Future opportunities include supplying new fodder markets and potential pharmaceutical and health uses for humans and livestock. New species could be considered in the future to overcome constraints of existing species, but their commercial success will depend upon perceived need, size of the seed market, ease of establishment, and management and safety of grazing animals and the environment. Molecular biology has a range of potential applications in pasture legume breeding, including marker-assisted and genomics-assisted selection and the identification of quantitative trait loci and candidate genes for important traits. Genetically modified pasture plants are unlikely to be commercialised until public concerns are allayed. Private seed companies are likely to play an increasingly important role in pasture legume development, particularly of mainstream species, but the higher risk and more innovative breakthroughs are likely to come from the public sector, provided the skills base for plant breeding and associated disciplines is maintained.
With limited funds, and the relatively low importance of dryland pastures in New Zealand, research has been targeted at the species most likely to induce transformational change on-farm. Lucerne research into biophysical influences on plant growth and development has added flexibility to spring grazing management. Coupled with additional agronomic research and extension, farmers now have the confidence to use lucerne as a direct feed source for sheep, beef and deer. Research on Caucasian clover seedling development identified the long duration to secondary leaf production as the physiological basis for slow clover establishment in mixed swards. Despite agronomic strategies to overcome this, its use is now limited by commercial constraints. A 10-year ‘MaxClover’ grazing experiment at Lincoln University demonstrated the superiority of subterranean clover with cocksfoot over perennial ryegrass and white clover for pasture persistence, quality and animal performance. Pastures with high legume content had higher water-use efficiency and produced greater animal and pasture production. Balansa and gland clovers both show a strong influence of photoperiod on time of flowering, which suggests they may be suitable for oversowing into areas of winter wet and summer dry hill and high country. Further research into their ecological niche and ability to regenerate each autumn is required. For all legumes, the role of inoculation requires further research with recent results suggesting indigenous, rather than commercially introduced, bacterial populations are dominant in root nodules. Uptake of dryland pasture species for on-farm use has only been successful when research, extension and agribusiness interests have been aligned.
Pastoral agriculture is unique among the world's agricultural production systems. Lucerne (also known as alfalfa), Medicago sativa L. subsp. sativa, has a long history of playing a very important role in pastoral agriculture. That role is expanding outside traditional hay and grazing production systems into sprouts for salads, nutritional supplements, and bioenergy feedstock. It is also the forage legume of choice for delivery of new traits via biotechnologies. The use of biotechnologies in lucerne improvement will cause re-examination of research methods and will require unique collaborations that are both interdisciplinary and even cross-institutional. The Consortium for Alfalfa Improvement (CAI) is discussed as a model for this type of collaboration. Breeding programs will continue development of cultivars with the proper fall (autumn) dormancy, a broad genetic base for pest resistance, increased local adaptation, persistence, and yield, while also adding new complex traits to these base traits. Increasing nutritional quality via down-regulation of lignin genes and increasing persistence via grazing tolerance, drought tolerance, and tolerance to acid, aluminium-toxic soils are discussed as examples of the potential impacts and challenges surrounding incorporation of complex traits. However, it is the potential for lucerne to become a major part of tropical or subtropical production systems or even an important adjunct to overcome deficiencies in the widely used perennial ryegrass (Lolium perenne L.) and white clover (Trifolium repens L.) temperate systems that begs further attention.
M. Z. Z. Jahufer, J. L. Ford, K. H. Widdup, C. Harris, G. Cousins, J. F. Ayres, L. A. Lane, R. W. Hofmann, W. L. Ballizany, C. F. Mercer, J. R. Crush, W. M. Williams, D. R. Woodfield, B. A. Barrett
Improving the genetic merit of temperate forage legumes helps ensure profitability and sustainability of our Australasian pastoral industries. Today’s plant breeders are supported by a range of underpinning research activities including genetic resources exploration and enhancement, plant physiology, plant health, feed quality, agronomy, quantitative genetics and plant biotechnology; and have collaborative interfaces with animal and farm systems science. Lifting the rate of gain by integration of molecular tools, innovative breeding strategies, and new genetic resources is the major objective of our white clover breeding network. This paper, presented at the Australasian Grassland Association’s recent Legume Symposium, focuses on the key research and development achievements in white clover breeding for Australasia, and on the success and future of an Australasian collaboration to breed improved cultivars for the region’s temperate environments. The paper reports on successful developments in the areas of improving white clover root systems for phosphate uptake, pest tolerance, development of novel inter-specific hybrids and marker-aided breeding. The successful trans-Tasman collaboration in white clover breeding and future work is also discussed.
Legume-based pastures, particularly those containing a large proportion of lucerne (alfalfa, Medicago sativa), have a prodigious capacity to fix atmospheric N2. Budgets of N show that permanent pastures in south-eastern Australia, when growing with no management limitations, can supply more N than is removed in animal products and can eventually lead to excess soil N. For a mixed crop–livestock farm, legume-dominant ley pastures occupying ∼40% of the land area can maintain a stable N balance. The actual performance of pastures on farms normally falls below the potential. Pastures are being replaced by crops in the wheat-sheep zone and, to a lesser extent, in the high-rainfall zone. Pasture productivity, as indicated by the area topdressed, the mean stocking rate, input of superphosphate and sale of pasture legume seed has decreased in the period 1990–2010. It is therefore likely that N2 fixation by pastures is falling sharply in the wheat–sheep zone and is static or falling slightly in the high-rainfall zone. Reversing the decrease in N2 fixation by pastures will become important if the real price of N fertilisers increases, as seems likely because the efficiency of fertiliser synthesis is approaching a maximum and the reserves of natural gas feedstock will eventually be depleted. Increased N2 fixation by pastures will depend on more profitable grazing industries, improved management methods and genotypes, and re-adoption of ley pastures by farmers. There is evidence that profitability of grazing enterprises is approaching that of crops so investment in pasture science is likely to lead to increased N2 fixation.
The amounts of foliage nitrogen (N) fixed by various annual and perennial legumes growing in Australian pastures range from <10 to >250 kg N/ha.year. Differences in N2 fixation result from variations in the proportion of the legume-N derived from atmospheric N2 (%Ndfa) and/or the amount of legume-N accumulated during growth. On-farm surveys of %Ndfa achieved by legumes growing in farmers’ paddocks in Australia indicated that N2 fixation contributed >65% of the legume’s N requirements in three-quarters of the annual legumes examined, but this decreased to two-thirds of lucerne (Medicago sativa; also known as alfalfa), and half of white clover (Trifolium repens) samples. Factors such as low numbers or the poor effectiveness of rhizobial strains in the soil, water stress, high soil concentrations of N, and nutrient disorders contribute to poor nodulation and %Ndfa values <65%, but there is also evidence that the observed %Ndfa can be dependent on the legume species present, and whether the legume is grown in a pure stand or in a mixed sward. The accumulation of legume-N relates primarily to the legume content and net productivity of the pasture. For many legume species, ∼20 kg of shoot-N is fixed on average for every tonne of herbage dry matter produced. Legume productivity can be influenced by (i) sowing and establishment techniques and other strategies that enhance the legume content in pasture swards; (ii) the amelioration of soil constraints; (iii) the use of new legume species (and host–rhizobial strain combinations) that are more tolerant of hostile soil environments than subterranean clover (T. subterraneum) or annual medics (Medicago spp); and (iv) the inclusion of perennials such as lucerne to offset the year-to-year variability in productivity and N2 fixation that is a common occurrence with annual legumes.
Quantitative measurement of N2 fixation has rarely been conducted in Australian dairy pastures. The available data indicate that annual N2 fixation rates in Australian dairy pastures are generally low, due to low pasture legume content. With typical legume contents of grazed pastures less than 30% of total pasture biomass production, annual N2 fixation in herbage is usually much less than 50 kg ha–1 year–1. Other factors which are likely to be able to contribute to increased N2 fixation input (rhizobia, mineral N management, soil acidity, soil water contents) will have little impact until such time as legume contents are increased. In contrast, for some hay systems, such as those using lucerne, N2 fixation input is shown to be high (200–300 kg ha–1 year–1).
While pasture clover contents remain low there is little value in study or measurement of N2 fixation, nor in complex modelling, as N2 fixation will be of little quantitative importance. However, where legume contents, and thus potential N2 fixation are increased, there is scope for investigation into potential increases in N input from this source, which is invariably linked to fertiliser application, the management of grazing and the N returns in urine and dung. These are the major influences on sward N dynamics and legume N2 fixation. The inoculant rhizobia used for white clover in Australia (TA1) is likely to be suboptimal. Isolated in Tasmania in 1953 it has been shown to be inferior in N2 fixation compared with other strains on several occasions. Root pests and diseases are likely to be prevalent and impact directly on clover root growth and perhaps nodulation.
Modelling is often used to describe the probable influence of management and/or climate on the operation of agricultural systems. Reliable modelling of N2 fixation requires capacity to integrate the effects of grazing and pasture composition on soil mineral N dynamics, the influence of this mineral N on nodulation and on suppression of N2 fixation, and environmental and management influences on soil rhizobial populations. Currently no models have demonstrated this capacity. At present, a suitably calibrated regression model is probably a good option for modelling N2 fixation in Australian dairy pastures.
Environmental benefits ensuing from increasing N2 fixation and substituting this for fertiliser N are likely to be greater off-farm (reduced GHG emissions at site of fertiliser manufacture) than on, if current fertiliser management is optimal. Nevertheless substituting fixed N for fertiliser N would have modest environmental and feed efficiency benefits.
Nutrient surpluses, inefficiencies in nutrient use, and inevitable leakage of nutrients from grazed animal production systems are putting growing pressure on Australian inland and coastal water resources. While there are some examples of regulatory policy approaches in Australia which aim to reduce nutrient emissions and improve water quality around important and impaired coastal and inland waters, most policy options involve voluntary schemes, often including financial incentives to both industry organisations and farmers to offset the costs of implementing improved management practices. In contrast, much stronger land management regulations have been implemented in the European Union, USA, and to a lesser extent New Zealand.
In the near future, greater societal expectations for water quality, stricter standards from international markets, and increasing costs for purchased nutrients will mean that improving nutrient-use efficiency and reducing nutrient losses will be a necessary part of Australia livestock production systems. This is likely to require somewhat varied and difficult choices to better balance production and environmental goals. Policy responses may include voluntary adoption of appropriate nutrient management practices, caps on nutrient inputs, mandatory nutrient surplus targets, limits to stock numbers per hectare, and re-positioning of higher input farms to more resilient parts of the national landscape. Alternatively, society may have to accept that there are unavoidable trade-offs between water quality standards and livestock productivity, with increasing treatment of polluted water at the community’s expense.
Biomass production, soil water extraction, and water-use efficiency (WUE, kg dry matter (DM)/ha.mm growing-season water use) of tropical, summer-growing and temperate, winter-growing forage legumes suited to short-term rotations with crops were compared over several growing seasons in southern Queensland. Tropical legumes lablab (Lablab purpureus cvv. Highworth and Endurance), burgundy bean (Macroptillium bracteatum cvv. Cardarga/Juanita mix), and butterfly pea (Clitoria ternatea cv. Milgara) were compared with forage sorghum (Sorghum spp. cv. Silk and cv. Sugargraze). Temperate legumes snail medic (Medicago scutellata cv. Sava), lucerne (Medicago sativa cv. UQL-1), sulla (Hedysarum coronarium cv. Wilpena), and purple vetch (Vicia benghalensis cv. Popany) were compared with forage oats (Avena sativa cv. Taipan/Genie). Production and WUE of winter legumes was highly variable, with oats producing more biomass than the legumes, except in 2009 where oat establishment was poor. In years with good establishment, WUE of oats (14–28 kg DM/ha.mm), snail medic (13–25 kg DM/ha.mm), and sulla (12–20 kg DM/ha.mm) were similar, but the production and WUE of vetch were generally lower (6–14 kg DM/ha.mm). Sulla dried the soil profile by 60–100 mm more than the annual species, but less than lucerne. Summer legumes, burgundy bean, and lablab performed similarly, although always produced less biomass and had lower WUE than forage sorghum. Lucerne extracted more water and maintained a drier profile by 70–150 mm and had lower WUE (<10 kg DM/ha.mm) than burgundy bean or lablab (9–30 kg DM/ha.mm). Of the legumes tested, burgundy bean and lablab seem the most likely to be profitably integrated into subtropical cropping systems. Further evidence of the rotational benefits provided by these legumes is required before they will be favoured over the perceived reliability and higher productivity of annual grass-type forages.
Biserrula pelecinus L. is a Mediterranean annual pasture legume and performs best on well drained sandy loams and medium loams with a pH 4.5–7. It is not suited to areas prone to waterlogging but persists well, even with hard summer grazing and in rotational systems. It is deep-rooted and remains green long after traditional pastures have dried off. Diversity analysis of germplasm collection of 279 accessions using 18 agro-morphological traits, 22 eco-geographical specifications of the collection sites, and amplified fragment length polymorphisms markers was conducted to develop a core collection of ∼10% of the original collection. This core collection of 30 accessions from seven countries well represented the diversity of the whole collection. This core will be exploited for variation in photosensitivity effect in sheep together with other economically important traits challenging the livestock industry.
The south-west of Western Australia has experienced a declining trend in annual rainfall and gradual warming over the last 30 years. The distribution of rainfall has also changed, with lower autumn rainfall, patchy breaks to the season, and shorter springs. This has important implications for the productivity of legume pastures in the region, which is dominated by annual species, particularly subterranean clover (Trifolium subterraneum L.), annual medics (Medicago spp.), serradella (Ornithopus spp.), and biserrula (Biserrula pelecinus L.). For annual pasture legumes, appropriate patterns of seed softening and germination behaviour, efficiency of phosphorus and potassium uptake, responses to elevated levels of atmospheric CO2, and drought resistance of seedlings and mature plants will assume increasing importance. While these traits can be targeted in pasture breeding programs, it will also be important to exploit farming system opportunities to optimise the annual legume component of the feed base. These opportunities may take the form of incorporating strategic shrub reserves and grazing crops to allow for pasture deferment in autumn–winter. Perennial forages may become more important in this context, as discussed in terms of the development of the perennial legume tedera (Bituminaria bituminosa var. albomarginata C.H. Stirton).
In the high-rainfall zone of Australia (HRZ, >600 mm), most pasture systems are dominated by perennial grasses with low levels of inter-dispersed legume. Numerous authors have shown that a legume content of 20–50% is required to maximise livestock production. Consequently, the legume content of these systems needs to be increased if livestock production is to be improved. Perennial legume options such as lucerne (Medicago sativa) and white clover (Trifolium repens) are limited in their application in this zone due to the sensitivity of lucerne to acid soils (pH(CaCl2) <4.8) and waterlogging and the inability of white clover to survive most of the annual summer droughts. To address this problem, a breeding program was undertaken to develop varieties of Lotus corniculatus (birdsfoot trefoil) suitable for the HRZ of southern Australia. In the first cycle, 365 populations were screened in nurseries to select the best 62 plants from the best populations at Yalanbee and Medina in Western Australia. These selections were then grown as half-sib families in spaced-plant nurseries at Waroona and Yalanbee; in the second cycle, 61 individuals, selected from the the two sites, were hand-crossed to produce 3160 plants from 202 pair-crosses. These were gown in a spaced-plant nursery at the University of Western Australia Field Station in Shenton Park. In the third cycle, three polycross populations (YF, T, and F) were produced from selections within the 3160 second-cycle plants, and two additional plants which survived for 4 years on a non-wetting sand at Yalanbee, including a significant drought year in 2006. These varieties are expected to extend the adaptation of L. corniculatus to drier areas and/or lower latitudes.
Preinoculation of seed is a convenient alternative method to inoculating seed on-farm. With preinoculation, a range of plant-growth and protection agents, polymer adhesives, colour pigments or dyes, and powder materials may be incorporated into an inoculant adhesive-slurry prior to seed coating. However, our recent point-of-sale surveys support findings of previous studies that survival of rhizobia on preinoculated seed is variable and can be poor. We focussed our research, both in the laboratory and at commercial facilities, on some of the factors that may contribute to poor survival of rhizobia on preinoculated seed. We found that rhizobial survival was affected by water quality; filtration improved cell survival but was not equal to distilled water. We also found that polymers affected cell survival differently for each rhizobial strain, and that slowing the desiccation rate reduced the cell rate of decline. Although fewer in cell number, older inoculant afforded more protection for survival of rhizobial cells. There is a need to test each ingredient and stage in the seed-coating process for compatibility to determine the best practices to promote rhizobial survival on seed. Failure to act on these factors prolongs the status quo of the findings from recent retail surveys.
Sulfonylurea (SU) herbicides are extensively applied to crops in the cereal-livestock zones of southern Australia. In low rainfall areas with alkaline soils, SU residues can persist over summer and can severely affect sown or regenerating medic pastures. A cohort of early season barrel medics (Medicago truncatula) bred and selected for tolerance to SU herbicide residues were evaluated at multiple field sites over 3 years (year of establishment and subsequent regeneration). Two lines (Z2438 and Z2415) were identified which had dry matter production and seed yield in the establishment year equivalent to their recurrent parent, Caliph, an early maturing, aphid-tolerant, barrel medic cultivar. They also had lower levels of hardseededness than Caliph, enabling them to regenerate in greater numbers in the following year and thus produce more dry matter. The two lines demonstrated good tolerance to simulated SU herbicide residues, producing up to 10 times the dry matter of the SU-intolerant parent Caliph. We anticipate that one or both of the two lines will be commercialised soon, enabling farmers in low rainfall areas with neutral-to-alkaline soils to successfully grow barrel medic pastures in the presence of SU herbicide soil residues resulting from applications to prior crops.
Spatial and temporal variation in soil Mn2 was observed over a 12-month period at two field sites near Gerogery and Binalong in southern New South Wales (NSW), Australia. Three pot experiments were then conducted to emulate the range of soil Mn2 concentrations observed in the field and to determine the effect of different concentrations on lucerne and subterranean clover seedling growth, as well as to determine the effect of heating a soil on pH and Mn2 concentrations. Concentrations of soil Mn2 in the surface 0.20 m varied at a given sampling date by up to 288% (2.5–9.7 µg/mL) and 183% (8.7–24.6 µg/mL) across the Gerogery and Binalong field sites, respectively. At both sites, the concentration of soil Mn2 in a given plot also varied by up to 175% between sampling times. There was little consistency between sites for seasonal fluctuations of soil Mn2 , although in both instances, peaks occurred during months in which newly sown lucerne plants might be emerging in southern NSW. Pot experiments revealed that high concentrations of soil Mn2 reduced lucerne seedling survival by 35%, and on seedlings that did survive, reduced shoot growth by 19% and taproot length by 39%. Elevated concentrations of soil Mn2 also reduced subterranean clover seedling survival by up to 55% and taproot length by 25%, although there were few effects on subterranean clover in treatments other than those imposing the highest soil Mn2 concentrations. The third pot experiment demonstrated that elevated soil temperatures led to increased soil pH and increased soil Mn2 concentrations, attributable to a decrease in biological oxidation of soil Mn2 . This was in contrast to the commonly anticipated response of a decline in soil Mn2 concentrations as soil pH increased.
Boron (B) is present at toxic levels in the subsoils of much of the semiarid south-eastern Australian cereal-livestock zone. Boron toxicity is typically associated with alkaline soils, where annual medics (Medicago spp.) are generally the best-adapted pasture legume. New medic cultivars have been developed for which there is no published B tolerance information. Five species of annual medic represented by 13 cultivars were grown in soil amended with B and evaluated for B tolerance. A rating system based on expression of symptoms was modified from earlier research. There was a wide range of response to B, both between and within species. Cultivars varied widely in their expression of symptoms; from showing no or few leaf symptoms (tolerant) to significant leaf necrosis (very sensitive). An integrated summary of both published and previously, unpubl. data for these and other medics is presented to provide a comprehensive and up-to-date comparison between different species and most commercial cultivars. This information will be useful for plant breeders, agronomists and farmers who manage soils with high B levels.
A new bluegreen aphid biotype (BGA, Acyrthosiphon kondoi Shinji) has been found in south-eastern Australia that causes severe damage and mortality in seedlings of previously resistant pasture legume cultivars. Populations of BGA collected at Urrbrae and Binnum, SA in 2009 caused 100% mortality in 29 cultivars of annual and perennial Medicago spp. and annual Trifolium spp. Delaying inoculation from the first trifoliate to the 6–8 trifoliate stage and removing susceptible genotypes from experiments had no impact on reducing mortality from 100% in previously resistant barrel medics. A half-sib family of lucerne from the SARDI breeding program has maintained resistance to the Urrbrae 2009 BGA.
A detailed study of the virulence of BGA populations collected from Toowoomba (Qld), Tamworth, Howlong (NSW), Launceston (Tas.), Colebatch, Kimba, Urrbrae and Vivonne Bay (SA) in 2010–11 on 33 pasture legumes provides evidence of new virulent BGA being widespread, despite these populations causing less severe damage and mortality than the two populations collected in 2009.
In the mid 2000s subterranean clover (Trifolium subterraneum) seed producers in South Australia reported symptoms of a red-leaf disease in fields with reduced seed yields. The red-leaf symptoms resembled those caused by several clover-infecting viruses. A set of molecular diagnostic tools were developed for the following viruses which are known to infect subterranean clover: Alfalfa mosaic virus; Bean leafroll virus (BLRV); Beet western yellows virus; Bean yellow mosaic virus; Cucumber mosaic virus; Pea seed-borne mosaic virus; Soybean dwarf virus and Subterranean clover stunt virus. Surveys of subterranean clover seed production fields in 2008 in the south-east of South Australia and western Victoria identified Bean leafroll virus, Alfalfa mosaic virus and Cucumber mosaic virus as present, with BLRV the most widespread. Surveys of pasture seed production fields and pasture evaluation trials in 2009 confirmed that BLRV was widespread. This result will allow seed producers to determine whether control measures directed against BLRV will overcome their seed losses. Bluegreen aphid (Acyrthosiphon kondoi) was implicated as a potential vector of BLRV because it was observed to be colonising lucerne plants adjacent to subterranean clover seed production paddocks with BLRV, and in a glasshouse trial it transmitted BLRV from an infected lucerne plant to subterranean clover in a persistent manner.
Lucerne is a deep-rooted herbaceous perennial legume with high levels of summer production and adaptation to a broad range of agro-ecological environments in southern Australia. The ability of lucerne to extend the growing season of winter-based pasture and respond quickly to rainfall after periods of drought makes it one of the most valuable plants in our feed base. However, for all the advantages of lucerne, it remains underutilised. Lucerne is often considered to be a speciality fodder crop, requiring careful management to achieve high levels of production and persistence. This paper investigates the opportunity of whole-farm integration of lucerne; from speciality fodder crop to traditional pasture. The future trends of lucerne production in temperate grazing and intensive dairy systems are discussed in relation to breeding objectives identified to meet these demands. If lucerne is to be used more commonly as a pasture, the plant and systems must adapt. This paper investigates the plant traits and management principles that are important for growing lucerne in mixtures with other plants and improving the integration of lucerne into the whole-farm plan.
The Australian Legumes Symposium was the first in a planned series of regular technical symposia organised by the Australian Grasslands Association. The aim was to provide researchers with the opportunity to interact, present up-to-date reviews on topics related to pasture legume science, present results of current research and participate in planning of future research and development relevant to pasture legumes. This paper is intended to be the key output of the forum – a summary of findings and highlights from review and contributed research papers as well as identifying key research priorities for the future. In terms of the former, reviews presented at the symposium provided an overview of the development and role of pasture legumes in temperate farming systems. Closely related topics – nitrogen (N) fixation, N balance of farming systems and management of legume inoculation provided a focus on the importance of legumes in terms of N input and overall productivity. International perspectives on lucerne – its improvement and adoption provided a noticeable contrast to the apparent paucity of research into this species in Australia – despite its widespread use in temperate farming systems. In terms of content, there were many other papers delivered dealing with a wide diversity of relevant issues. On one hand the diversity of work in pasture legume research and development may stem from the wide array of expertise available in Australia and New Zealand, while on the other it might suggest that research and development inputs are being thinly spread over a large number of species.
With respect to determining research priorities, it was surprising that participants were most concerned with how research is funded and conducted and the need to address this by reconsidering current arrangements. A greater role for economic analysis in determining research priorities was foreshadowed. The identification and management of acid-tolerant perennial legumes for higher rainfall zone permanent pastures was nominated as a major research priority, as was the need to address problems related to pre-inoculation of legume seed. The clear message from the symposium was that there needs to be a reorganisation of pasture legume improvement in order for gains to be effectively realised, and to maintain research and development capacity.
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