Annual Medics Research Articles

The effect of crop rotation and tillage practice on Fusarium crown rot and agronomic parameters of wheat in South Africa

Fusarium crown rot (FCR) of wheat (Triticum aestivum) is a stubble-borne disease of global concern and a known yield-limiting factor in the Western Cape Province of South Africa. Disease management options is limited, with a focus on crop rotation and tillage, the effect of which has not yet been quantified locally. Crop rotation and tillage practices were, therefore, investigated in two wheat production areas of the Western Cape over two years (2020 and 2021) to determine its effects on FCR disease- and agronomic parameters of wheat. Crop rotation with non-host crops, including annual medics (Medicago spp.), canola (Brassica napus) and lupin (Lupinus spp.) significantly reduced FCR disease incidence and severity, while increasing grain yield and quality over the two-year study period. Significant negative correlations (P < 0.05) were established between FCR disease incidence and – severity with grain yield and – quality. Tillage practices were comprised of conventional tillage (deep soil disturbance with a plough), minimum tillage (shallow tine tillage), no tillage (no primary soil disturbance, tine planter) and zero tillage (no primary soil disturbance, disc planter). Zero tillage decreased FCR incidence and disease severity, without impeding wheat grain yield and quality. Better soil water conservation later in the season, along with shallower seeding depth in zero tillage, contributed to FCR disease management. Crop rotation with non-host crops, combined with zero tillage can, therefore, be integral to FCR disease management strategies.

Cereal and oil seed crops response to organic nitrogen when grown in rotation with annual aerial-seeded pasture legumes

AbstractNitrogen fixation from pasture legumes is a fundamental process that contributes to the profitability and sustainability of dryland agricultural systems. The aim of this research was to determine whether well-managed pastures, based on aerial-seeding pasture legumes, could partially or wholly meet the nitrogen (N) requirements of subsequent grain crops in an annual rotation. Fifteen experiments were conducted in Western Australia with wheat, barley or canola crops grown in a rotation that included the pasture legume species French serradella (Ornithopus sativus), biserrula (Biserrula pelecinus), bladder clover (Trifolium spumosum), annual medics (Medicago spp.) and the non-aerial seeded subterranean clover (Trifolium subterraneum). After the pasture phase, five rates of inorganic N fertilizer (Urea, applied at 0, 23, 46, 69 and 92 kg/ha) were applied to subsequent cereal and oil seed crops. The yields of wheat grown after serradella, biserrula and bladder clover, without the use of applied N fertilizer, were consistent with the target yields for growing conditions of the trials (2.3 to 5.4 t/ha). Crop yields after phases of these pasture legume species were similar or higher than those following subterranean clover or annual medics. The results of this study suggest a single season of a legume-dominant pasture may provide sufficient organic N in the soil to grow at least one crop, without the need for inorganic N fertilizer application. This has implications for reducing inorganic N requirements and the carbon footprint of cropping in dryland agricultural systems.

Sequential infections by 32 isolates of

Context Studies of Phoma black stem and leaf spot disease (caused by Phoma medicaginis) in annual medics (Medicago spp.) normally involve a ‘once-only’ inoculation not reflecting multiple pathogen infection and phytoestrogen production cycles in the field. Phytoestrogen production by plants can result in lower ovulation rates in grazing animals. Aims We aimed to determine whether sequential infections by P. medicaginis increase production of phytoestrogens in annual medics, and to measure the genetic diversity of isolates. Methods In a greenhouse experiment, pathogenicity and virulence were investigated across 32 isolates of P. medicaginis following one, two or three rounds of inoculation of M. polymorpha var. brevispina. Production of the phytoestrogens coumestrol and 4′-O-methyl coumestrol was measured, and correlation with disease parameters assessed. DNA sequencing using ITS, β-tubulin, calmodulin and P. medicaginis-specific EFNI-1α was applied for phylogenetic analysis of isolates from Western Australia and elsewhere. Key results Across isolates, highest leaf disease incidence was 76%, petiole disease incidence 61%, leaf disease severity 52% and petiole disease severity 53%. Stem coumestrol content range was 45–1247 mg kg−1, and 4′-O-methyl coumestrol 0–344 mg kg−1. All measures were highest after three rounds of inoculation. Overall, there was a positive correlation of leaf disease incidence with coumestrol content (P &lt; 0.05) and of both leaf and petiole disease incidence with 4′-O-methylcoumestrol content (P &lt; 0.01, P &lt; 0.05, respectively). Phylogenetic analysis revealed a high degree of genetic similarity among Western Australian isolates, generally grouping into a single separate cluster across the four markers, and genetically distinct from isolates sourced outside Australia. Conclusions Leaf disease incidence was the best discriminating disease parameter for coumestrol and 4′-O-methylcoumestrol content. Western Australian isolates of P. medicaginis were genetically similar and unique, possibly due to geographic separation. Implications The study emphasised the importance of sequential inoculations when screening annual Medicago genotypes towards developing cultivars with superior disease resistance and enhanced animal reproductive outcomes.

Induction of Autotetraploidy and its effects on morphophysiological traits in some annual and perennial medics

In order to study of the effects of polyploidy on morph-physiological traits in some annual and perennial medics, five annual and three perennial diploid medics were subjected to different concentrations of colchicine solution (0.1%, 0.5%, 1% and 2%) in mitosis stage. The induced tetraploids were identified by counting stomata guard cells chloroplasts. The highest survival rate and tetraploidy induction with average values of 80.2% and 74.3% were obtained using 0.1% colchicine concentration. All of the 21 entries (5 annual diploids and their induced tetraploids as M. lupulina, M. radiata, M. rijidula, M. truncatula, M. turbinata, and 3 populations of perennial diploid of M. sativa ssp. Caerulea (Karaj1, Karaj2 and Tehran) and their induced tetraploids and 5 commercial tetraploid alfalfa cultivars (Bami, Hamadani, Baghdadi, Ghareyongeh and Renger) grown in pots in a glasshouse experiment using completely randomized design with five replications in 2018 in Ahvaz, Iran. Data were collected for leaf length, leaf width, shoot and root length, seedling weight, shoot weight, root weight, branch number, leaf area index (LAI) and water use efficiency (WUE). Result of mean comparisons between three groups (2x, induced 4x and controls 4x), showed that both groups of induced and natural tetraploids had significantly higher mean values for all the traits except leaf length, shoot length and root length than that for diploids. For the latter traits there were no significant differences between 2x and induced 4x. On the overall, the induced 4x had 60%, 62%, 68%, 65%, 22%, 109% and 47% higher mean values than their parental 2x for seedling weight, shoot weight, root weight, LAI, WUE and branch number, respectively. It was concluded that increasing ploidy level provides plant breeders with a promising tool in the breeding improve new varieties suited for future climate scenarios.

An Annotated List of Legume-Infecting Viruses in the Light of Metagenomics.

Legumes, one of the most important sources of human food and animal feed, are known to be susceptible to a plethora of plant viruses. Many of these viruses cause diseases which severely impact legume production worldwide. The causal agents of some important virus-like diseases remain unknown. In recent years, high-throughput sequencing technologies have enabled us to identify many new viruses in various crops, including legumes. This review aims to present an updated list of legume-infecting viruses. Until 2020, a total of 168 plant viruses belonging to 39 genera and 16 families, officially recognized by the International Committee on Taxonomy of Viruses (ICTV), were reported to naturally infect common bean, cowpea, chickpea, faba-bean, groundnut, lentil, peas, alfalfa, clovers, and/or annual medics. Several novel legume viruses are still pending approval by ICTV. The epidemiology of many of the legume viruses are of specific interest due to their seed-transmission and their dynamic spread by insect-vectors. In this review, major aspects of legume virus epidemiology and integrated control approaches are also summarized.

Sensitivity of the messina (

Messina (Melilotus siculus) is a new annual pasture legume with better combined waterlogging and salt tolerance than other annual legumes. Messina cv. Neptune and a new salt-tolerant rhizobial symbiont (Sinorhizobium medicae SRDI-554) were made available to Australian growers in 2017. Messina is related to the annual medics (Medicago spp.) that are nodulated by the same genus of rhizobia and regarded as sensitive to soil acidity. Because some saltland soils are acidic, it is important to understand the sensitivity of messina to soil acidity in order to avoid failures during early adoption. Acidity tolerance of the messina–Sinorhizobium symbiosis was investigated in a hydroponic experiment (inoculation with SRDI-554, or the salt-intolerant strain WSM-1115 recommended for medics), and in three acidic soils (pHCa 4.3–5.5) (inoculation with SRDI-554 ± lime pelleting of seed), in the greenhouse. In the hydroponic experiment, the percentage of messina plants (with SRDI-554) that formed nodules declined at pH levels between 5.7 (43%) and 5.5 (4%). Strain SRDI-554 was slightly more sensitive to acidity than strain WSM-1115. In the acidic soils, more plants formed nodules than in the hydroponic experiment at similar pH levels; however, without lime pelleting, nodule number was inadequate at soil pHCa &lt;5.5. Addition of lime to seed was beneficial to messina nodulation. Nodule number per plant increased from 4.0 to 9.6 with the addition of lime. The messina–Sinorhizobium symbiosis was confirmed as sensitive to low pH. At pHCa 5.5, which is the level recommended as the lower limit for growing messina, nodule number was constrained in both hydroponics and soil. The risk of suboptimal nodulation would be reduced if the recommended lower soil pH limit for growing messina is increased to pHCa 5.8, in line with most annual medics. Efforts to improve the acidity tolerance of the messina symbiosis would be best focused on the rhizobial symbiont, rather than the plant.

Rhizobium inoculants for alfalfa in acid soils: A proposal for Uruguay

Ensifer meliloti establishes symbiosis with Medicago sativa (alfalfa) and other perennial species of Medicago that grow in soils with neutral to alkaline pH, whereas Ensifer medicae makes symbiosis with annual medics adapted to moderately acid soils. The new species Rhizobium favelukesii, whose strain is LPU83, belongs to an alfalfa group of inefficient rhizobia, known as the Oregon type, initially represented by Rhizobium sp. strain Or191. R. favelukesii is considered a potential risk in the acid soils where alfalfa is grown, and could explain the inefficient nodulation observed in different countries. In acidic soils from the «Dairy Basin» of Uruguay, producers inoculate alfalfa with E. melliloti U143 strain. This edaphic condition is often marginal because the maximum potential of rhizobia-alfalfa symbiosis is not achieved at acid pH. Although Uruguay has an outstanding position in the production and use of rhizobial inoculants, the commercial strains currently used in Trifolium, Lotus and alfalfa were selected about 50 years ago in different conditions that the present ones as a consequence of: i) the displacement of cultivated pastures to other sites, ii) the sowing method, and iii) the use of new cultivars. In this review, alfalfa inoculation is analyzed in some countries and a strategy for the development of an inoculant suitable for Uruguayan acid soils is proposed. This strategy is based on the selection of efficient and competitive strains, as the first selection criteria, and persistency in soil as the second one.

Cold-tolerant germplasm identified in annual medics (Medicago spp.) collection of National Plant Gene Bank of Iran

ABSTRACTAnnual medics are feed legumes that can be used as a cover crop or green manure. Species such as Medicago scutellata are sensitive to cold stress. To identify cold-tolerant germplasm, 351 accessions of Iranian annual medics, belonging to 13 species, were evaluated. Growth rate was scored for each accession from autumn to spring. Based on first-year results, M. coronata, M. laciniata, M. littoralis, M. turbinata, and M. scutellata were identified as cold-sensitive species, whereas four species [M. minima (5 accessions), M. noeana (2 accessions), M. rigiduloides (4 accessions), and M. rigidula (5 accessions)] were found to be cold-tolerant and tested further using a randomized complete-block design with three replications. Significant differences (p < 0.01) among accessions for agronomic traits (forage-, seed-, and pod-yield; percentage of green cover) were detected. M. rigiduloides, M. rigidula, M. minima, and M. noeana were cold-tolerant in descending order. Such cold-tolerant accessions can be used in breeding programs to develop cold-tolerant varieties.

A noncanonical poly(A) RNA polymerase gene affects morphology in Phoma medicaginis

Phoma medicaginis (syn. Ascochyta medicaginicola Qchen & L. Cai) causes spring black stem and leaf spot, an important disease of alfalfa and annual medics. P. medicaginis forms uninucleate conidia in melanized pycnidia and is genetically tractable using Agrobacterium mediated transformation (ATMT), resulting in random integration of T-DNA that occasionally generates pycnidial mutants. The T-DNA tagged mutant, P265 displayed smaller pycnidia and more aerial hyphae than the wild type. A single T-DNA disrupted a putative noncanonical poly(A) RNA polymerase gene, Pmncpap1, which in yeast interacts with ribonucleotide reductase (RNR). As in yeast mutants, P265 showed sensitivity to hydroxyurea (HU), a RNR inhibitor. To characterize the role of Pmncpap1, targeted ΔPmncpap1 mutants were created using a hygromycin selectable marker flanked by 1 Kbp regions of Pmncpap1. ΔPmncpap1 mutants possessed similar morphological features to those of P265. The plasmid for rescue of PmncPAP1, pCAM−Nat1 (nourseothricin selection) was constructed and used to introduce full-length PmncPAP1 into mutants. Rescued P265 showed partial recovery of wild type and the original T-DNA was lost due to homologous integration. To our knowledge, this is the first ncPAP to be examined in a filamentous fungus.

Effect of varying degrees of plant residue cover from different crops on annual medic pasture re-establishment and production

Annual medics can play an important role as a pasture crop in short-rotation pasture-cropping systems in the Overberg district of South Africa. Permanent soil cover, an important aspect of conservation agriculture, and different crops in rotation may be, amongst other factors, detrimental to annual medic re-establishment and production. A field study was conducted to test re-establishment and subsequent production of medic pasture under varying degrees of cover (0%, 25%, 50%, 75% and 100% cover) from wheat, barley, oats and annual medic residues. Medic pastures showed the highest re-establishment and production if following wheat in a cropping system. The re-establishment and production of annual medics did not differ significantly from 0% to 75% cover, whilst 100% cover decreased re-establishment and production significantly.

The effect of pod elimination on water stress in relation to antioxidant enzymes activity and proline in three annual medics species

Despite the importance of pod removal in the seeds of annual medics, there have been few studies carried out in this area. In this research, the role of pod removal in growth and biochemical enzyme activities was examined in three annual medic species during drought stress and subsequent recovery. This study was carried out as a factorial experiment based on a completely randomized design. The treatments were carried out on annual medic species of three levels: Medicago rigidula, M. scutellata, M. polymorpha, presence or removal of the pod and water stress. Water stress was split into the following four levels: 100%, 80%, 60%, and 40% field capacity (FC) during the stress period. The results showed that drought stress and subsequent recovery increased proline content and antioxidant enzyme activity. The highest proline content and antioxidant enzyme activity was observed in M. Scutellata. However, the rate at which proline increased, decreased at 40% FC whereas the antioxidant enzyme reached their highest activity at 40% FC. The antioxidant enzymes’ activity and proline content without the pod experiment were significantly higher than with the pod experiment. Since the activation of an antioxidant system and the increasing of the proline content helps the plants with stress induced damages, our results indicated that elimination of pods of annual medics before sowing helps seedlings to perform better under drought stress. This data is useful to gain a better understanding of the physiological basis of the changes in drought resistance as well as the crop breeding projects.

Impact of Nanosized Titanium Dioxide on Agronomical and Physiological Characteristics of Annual Medic (Medicago scutellata L.)

Abstract In order to investigate the effect of exogenous application of nano-TiO2 on annual medic, a field study was conducted in a factorial design based on randomized complete blocks with four replications. The experimental treatments included six concentrations of nano-TiO2 (Control, 0.01%, 0.02%, 0.03%, 0.04%, 0.06% g/l) and spraying at two growing stages (pod stage and 10% flowering stage). Results showed that the effects of nano-TiO2 and spraying times on dry forage yield were significant (p&lt;0.01). Nano-TiO2 spray appear to influence the malone dialdehyde (MDA) content (p&lt;0.01). With increasing concentrations of nano-TiO2 the values of aforementioned measured variable significantly decreased. The activities of antioxidant enzymes, including catalase (CAT), ascorbate peroxidase (APX) and guaiacol peroxidase (GPX) were affected by nanoparticle (p&lt;0.01) and spraying times (p&lt;0.01), as well as their interactive effect of two mentioned factors were significant in terms of guaiacol peroxidase (GPX) (p&lt;0.01) activity and dry forage yield. Among different concentrations of nano-TiO2, 0.04% and 0.06% have the best effect on all traits. Totally, treatment with nano-TiO2 were more effective in the pod stage, compared to 10% flowering stage.

Annual forage legumes in dryland agricultural systems of the West Asia and North Africa Regions: research achievements and future perspective

AbstractForage legumes are vitally important to animal production in the dryland farming systems of the Mediterranean region. Of the diverse forage‐legume species adapted to the Mediterranean climate, vetches, (Vicia spp.), chicklings (Lathyrus spp.), annual medics (Medicago spp), clovers (Trifolium spp.) and species of the Lupinus, Lotus, Onobrychis, Hedysarum and Ornithopus genera are considered to be the most agronomically important and economically valuable species for the region. Adoption of perennial self‐regenerating medic (Medicago spp.) has been limited because of technical difficulties, but annual vetch (Vicia spp.) has the greatest potential as a viable animal‐feed source and a rotation crop with cereals. Some forage legumes survive harsh conditions by their unique underground growth habit, for example, V. amphicarpa and Lathyrus ciliolatus. Efforts to improve forage legumes have been based on both management/cultural factors and breeding. Research based on several long‐term barley‐ and wheat‐based rotation trials has demonstrated the viability of forage legumes, especially vetch, in the region's improved farming system. An additional benefit to such legumes is the enhancement of soil quality, that is, soil fertility, soil organic matter and soil physical properties. Thus, the development of forage legumes is essential to agricultural sustainability in the Mediterranean region and in other dryland cereal‐growing areas of the world where grazing livestock is a dominant enterprise. To build upon the considerable research conducted on forages, intensified efforts are needed to develop locally adapted forage cultivars, to provide economic assessment of forages in cropping systems and to promote technology transfer at the farm and community level.

Seed Persistence in Soil of Five Medic Cultivars in Southeastern Wyoming

ABSTRACTThe success of annual medic pastures in ley farming systems is largely due to their ability to establish and maintain a viable seed bank from which these pastures can annually regenerate. A medic pod burial study was conducted to evaluate seed bank persistence of a range of commercially available and experimental annual medic lines under field conditions in southeastern Wyoming. The Medicago rigidula (L.) All. (tifton burclover) cultivar Laramie had the highest proportion of hard seed throughout the study period (1997–2001). After 5 yr of pod burial, this cultivar retained 56% of the original seed bank as hard seed within 5 cm of the soil profile depth. In contrast, the best of the Australian‐developed cultivars Santiago (burr medic [Medicago polymorpha L.]) maintained 48% hard seeds within 5 cm soil depth after 3 yr of pod burial. The remaining Australia developed cultivars maintained at least half the seed bank for just 1 yr at either the surface or 5 cm depth. Our results demonstrated that Laramie annual medic has the ability to produce a large and viable seed bank capable of persisting for an extended period in southeastern Wyoming ley farming systems.

Infertility in the Southern White Rhino: Is Diet the Source of the Problem?

Infertility in the Southern White Rhino: Is Diet the Source of the Problem?

Characterization and Effectiveness of Co‐inoculation of Sinorhizobium Strains on Annual Medics

ABSTRACTSelection and identification of better‐adapted annual medics with an appropriate rhizobia inoculum is crucial for improved forage quality and yield. The objectives of this study were to characterize 11 rhizobial strains used for an effectiveness study on annual medics and generate an inoculum blend suitable for annual medic species adapted to the southern Great Plains. Each strain was compared to reference rhizobia strains by polymerase chain reaction (PCR) based on repetitive sequences (rep‐PCR) and ribosomal gene sequences and analyzed for plant growth promoting (PGP) activities. Genetic characterization separated the strains into two groups belonging to Sinorhizobium medicae (seven isolates) and Sinorhizobium meliloti (four isolates). Three of the 11 strains tested positive for the PGP activities of indole acetic acid production and phosphate solubilization. A blend of three strains (NFmix3, consisting of WSM1115, 102F85, and M49), of which two were positive for PGP activities, was used in an effectiveness study for the annual medics Medicago minima (L.) Bartal., Medicago orbicularis (L.) Bartal., Medicago rigidula (L.) All., and Medicago rigiduloides E. Small. The NFmix3 association with three of the four annual medic species resulted in equivalent biomass production as that of the single specific strain. The NFmix3 blend would be suitable and more economic for use with a mixture of medic species that may provide expansion of the grazing season.

Boron tolerance in annual medics (Medicago spp.)

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.

Virus diseases of annual pasture legumes: incidences, losses, epidemiology, and management

This paper reviews current knowledge concerning the occurrence, losses caused, epidemiology, and management of virus diseases of annual pasture legumes. The viruses commonly present are spread by contact, or aphid vectors either non-persistently or persistently. Whether they are seed-borne and their means of transmission are critical factors determining their incidences within pastures in climatic zones with dry summers or substantial summer rainfall. Large-scale national or state surveys of subterranean clover pastures revealed that some viruses reach high infection incidences. Contamination with seed-borne viruses was widespread in plots belonging to annual pasture legume improvement programs and seed stocks of subterranean clover, annual medics, and alternative annual pasture legumes, and in commercial annual medic seed stocks. Yield loss studies with grazed swards were completed for three common viruses: two in subterranean clover and one in annual medics. These studies demonstrated considerable virus-induced losses in herbage and seed yields, and established that virus infection causes deteriorated pastures with high weed contents even when foliar symptoms are mild. Comprehensive integrated disease management tactics involving phytosanitary, cultural, chemical, or host resistance measures were devised for these three viruses in infected pastures, and for seed-borne viruses in annual pasture legume improvement programs. Several other viruses are potentially important, but, with these, quantification of losses caused in grazed swards is lacking and information on incidences in pastures is currently insufficient. Critical research and development gaps that need addressing are identified.

Breeding and farming system opportunities for pasture legumes facing increasing climate variability in the south-west of Western Australia

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).

Temperate pasture legumes in Australia—their history, current use, and future prospects

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.