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The introduction of exotic pasture germplasm has formed the foundation of many Australian grazing systems. Scientists have searched the world for plants to improve the feedbase, amassing collections of diverse genetic material, creating genebanks that have made a large contribution to feedbase productivity. These genebanks contain a vast range of legumes, grasses, herbs and shrubs with growth habits ranging from small herbaceous plants to woody trees and life cycles from annuals to short- and long-term perennial plants. They have been collected from cool temperate to tropical climates and arid to high-rainfall zones. Hundreds of cultivars have been developed from material either collected by Australian plant breeders overseas or introduced from overseas genebanks. The collection of this germplasm has enabled plant breeders to extend the area of adaptation of species into climates, soils and systems previously considered marginal. The importance to Australian and world agriculture is increasing as plant breeders seek traits to meet the challenges of a changing climate and animal production systems. Furthermore, urbanisation, landscape degradation and political instability are making it increasingly difficult to collect pasture and forage germplasm from native grasslands in many countries. This emphasises the need to maintain and improve the capacity of the Australian Pastures Genebank (APG). The APG houses ~85 000 accessions and is a modern, online source of diversity for plant scientists around the world. This paper summarises the history of the founding genebank collections, their environment and farming systems focus, and the visionary and resourceful individuals that built them.

Management and distribution of experimental data from prebreeding projects is important to ensure uptake of germplasm into breeding and research programs. Being able to access and share this data in standard formats is essential. The adoption of a common informatics platform for crops that may have limited resources brings economies of scale, allowing common informatics components to be used across multiple species. The close integration of such a platform with commonly used breeding software, visualization, and analysis tools reduces the barrier for entry to researchers and provides a common framework to facilitate collaborations and data sharing. This work presents significant updates to the Germinate platform and highlights its value in distributing prebreeding data for 14 crops as part of the project ‘Adapting Agriculture to Climate Change: Collecting, Protecting and Preparing Crop Wild Relatives’ (hereafter Crop Trust Crop Wild Relatives project) led by the Crop Trust (https://www.cwrdiversity.org). The addition of data on these species compliments data already publicly available in Germinate. We present a suite of updated Germinate features using examples from these crop species and their wild relatives. The use of Germinate within the Crop TrustCropWildRelatives project demonstrates the usefulness of the system and the benefits a shared informatics platform provides. These data resources provide a foundation on which breeding and research communities can develop additional online resources for their crops, harness new data as it becomes available, and benefit collectively from future developments of the Germinate platform.

The phenotypic diversity and productivity of a diverse alfalfa (M. sativa subspp.) panel of cultivars, landraces and wild relatives with putative drought tolerance were evaluated in two Mediterranean environments (central Chile and Southern Australia). In Chile, 70 accessions were evaluated in rainfed conditions and in Australia 30 accessions under rainfed and irrigated conditions, during three growing seasons. Large phenotypic variation was observed among and within subspecies for NDVI, stem length, intercepted PAR and forage yield. Principal component analysis indicated that the first two principal components (PC) accounted for 84.2% of total variance, fall dormancy, taxa, and breeding status were closely related to the agronomical performance of alfalfa accessions. Forage yield varied largely among accessions across years and locations. A linear relationship was found between annual forage yield and annual water added to the experiments (R2 = 0.60, p &lt, 0.001). The GxE analysis for forage yield allowed the detection of the highest yielding accessions for each of the two mega-environments identified. The accessions CTA002 and CTA003 showed greater forage yield in both Chile and Australia environments. It is concluded that new breeding lines derived from crosses between cultivated alfalfa (M. sativa subsp. sativa) and wild relatives belonging to the primary (M. sativa subsp. falcata) and tertiary (M. arborea) gene pool, achieve outstanding agronomical performance in drought-prone environments.

Acidic conditions with damaging levels of available aluminium (Al3+) currently limit lucerne (Medicago sativa) production on soils in the New Zealand high country and in large areas of Australia. Increased lucerne nodulation could be achieved by using an Al3+-tolerant strain of Sinorhizobium meliloti to inoculate an Al3+-tolerant lucerne line. The Al3+ tolerance of the current commercial Australasian inoculant strain for lucerne, S. meliloti RRI128, was compared with strain SRDI736, selected in Australia for tolerance to low pH. Four Al3+ levels (0, 2, 4 and 8 µm) were created at pH 5.1 in a hydroponic system. The rhizobial strains were evaluated on SARDI AT7, a lucerne line selected for improved growth and nodulation in acidic solution culture with Al3+, and on Stamina 5, a commercial cultivar commonly grown in Australasia. SARDI AT7 when inoculated with strain SRDI736 produced more nodules per plant (3.6 vs 2.4) and had higher nodulation percentage (>80% vs 3 mg kg–1 soil) was also investigated in a pot trial. Lime had a more consistent effect than inoculant strain for increasing nodulation. At 0.5 and 2 t lime ha–1, plants inoculated with strains SRDI672 and SRDI736 had more nodules per plant than plants inoculated with the commercial strain. At 4 t lime ha–1, the number of nodules per plant was highest for all three inoculants, and there were no differences among them. This confirms the importance of lime to increase lucerne nodulation in low-pH, high-Al3+ soils. However, where liming is uneconomic or impractical, the results show that it was possible to select rhizobial strains to increase lucerne nodulation in acidic soils with damaging levels of available Al3+.

The potential for alfalfa to be a valuable rainfed pasture option that can be used to increase livestock and crop production in central-south Chile is demonstrated for the first time. The persistence, productivity and water use efficiency of alfalfa (Medicago sativa) cultivars was evaluated at four sites in dryland Mediterranean environments of Chile between 2012 and 2015. Nine alfalfa cultivars were evaluated for plant persistence, winter growth, forage yield, shoot water potential (Ψ), stomatal conductance (gs), and carbon (δ13C) and oxygen (δ18O) compositions. The percentage of plant survival after four years varied between 69 and 97% of the established plants. Alfalfa forage yield was >9 t ha−1yr−1 at Yungay (Andes foothills) in year two, and at Cauquenes (interior dryland site) in years three and four. The highest forage yield was obtained in cultivars SARDI Ten and Aquarius and the lowest in WL326HQ. In 2015, the forage yield during late spring and early summer (November 2015–January 2016) ranged from 3170 to 3570 kg ha−1 (average of the nine cultivars), which represented between 29% and 38% of the total production. The response of gs to Ψ was different among cultivars but all cultivars exhibited a strong decline when Ψ was 16 kg mm−1). It is concluded that alfalfa is a high yielding forage that can extend the growing season into early summer and autumn in dryland Mediterranean environments.

Context Near-infrared reflectance spectroscopy (NIRS) is a tool that permits rapid and inexpensive prediction of the nutritional characteristics of forages consumed by ruminants. Aim Our aim was to investigate the feasibility of developing a NIRS calibration to predict the nutritional value of the majority of grasses, legumes and forbs that are utilised for sheep and cattle production in southern Australia. Methods More than 100 annual and perennial forage species were grown in replicated plots at two locations over a period of 3 years. Biomass was sampled every 3–6 weeks, dried, ground and scanned with a desktop NIRS machine (n = 4385). One-quarter of these samples were subjected to laboratory analysis for calibration development or validation. Key results Despite the large variation in the taxonomy and maturity of the plants when sampled, we successfully developed broad calibrations that predicted key nutritional traits. We achieved excellent predictions for crude protein, with a ratio of standard error of performance:standard deviation (RPD) of 5.3, and standard error of cross validation (SECV) of 1.06%. Predictions of neutral detergent fibre were also excellent (RPD 4.3, SECV. 3.5%). For pepsin–cellulase DM digestibility and acid detergent fibre, predictions were very good (RPD 3.7, SECV 2.6% and RPD 3.9, SECV 2.1%). Predictions for organic matter were less reliable (RPD 2.2). We achieved very promising predictions of methane production during batch culture fermentation (RPD 3.1, SECV 3.5 mL/gDM). Predictions of ammonia and total volatile fatty acid concentrations in the post-fermentation substrate were poor. Conclusions We found that the broad calibrations predicted the nutritional traits of annual grasses, annual legumes and forb species with greater accuracy than perennial grasses or legumes. This could be associated with the accuracy of the wet chemistry methods. As a general rule, separating taxonomically similar species into groups before the development of calibrations, did not lead to more accurate predictions. Implications If more spatial and temporal diversity can be built in without a large reduction in accuracy, these broad NIRS calibrations represent a valuable tool for Australian researchers, feed testing agents and livestock producers, as they encompass nearly all of the species that appear in monocultures or mixed swards.

Effects of micronutrients [molybdenum (Mo), boron (B), iron (Fe), zinc (Zn), manganese (Mn) and copper (Cu)] on seed yield and yield components (seed yield per unit area, fertile shoots per unit area, number of racemes per shoot, number of pods per raceme, number of seeds per pod and 1000-seed weight) of alfalfa were investigated in the northwest region of China, over two seasons (2003–2004) on a torrifluvent soil and a site of 1720 m altitude. After two years study, it demonstrated that molybdenum and boron were more critical for alfalfa seed production. Molybdenum increased seed yield by 27–47%, the number of racemes per shoot by 38–55%, the number of pods per raceme by 100–133%, the number of seeds per pod by 48–61% and 1000-seed weight by 24%, and boron increased seed yield by 22–35%, fertile shoots per unit area by 17–35%, the number of racemes per shoot by 38–64%, the number of pods per raceme by 100%, the number of seeds per pod by 41–52% and 1000-seed weight by 16%. Iron, manganese, and c...

Effects of 0.3, 0.5, and 0.7% chlormequat, 0.15 and 0.35% ethephon, and 0.12 and 0.22% paclobutrazol on lucerne growth and components of seed yield were investigated in Gansu province, China. The paclobutrazol application decreased above- and below-ground biomass by 25-48 and 44% at concentrations of 0.12-0.22%, and increased seed yield by 31-47%. Applications of ethephon and chlormequat did not affect lucerne biomass, but reduced seed yield in the first year. Plant growth regulators also affected yield components very differently, with paclobutrazol having the greatest effect. The 0.22% paclobutrazol application increased the number of racemes per shoot by 38%, the number of pods per raceme by 392% and the number of seeds per pod by 115%. Although ethephon and chlormequat reduced seed yield in the first year and gave no response in the second, these plant growth regulators had some positive affects on some seed yield components. The 0.15% ethephon application increased the number of racemes per shoot by 35% and the number of pods per raceme by 225%. The 0.3% chlormequat application increased the number of fertile shoots per unit area by 24% and number of pods per raceme by 178%. None of the plant growth regulators had ill effects on lucerne seed quality (1000-seed weight and seed germination). Among yield components, the number of pods per raceme and number of seeds per pod were the most important factors to determine lucerne seed yield and yield potential can be estimated with the use of the two factors as a selection criterion. Results from this study will be used to recommend further evaluation of paclobutrazol at multiple sites and to guide lucerne seed production in the north-west region of China.

The objective of this study was to quantify the genetic variability and determine the inheritance of Al tolerance in lucerne (or alfalfa) using a 4-parent diallel mating design. Regrowth root length (RRL), along with root length (RL) and total root length (TRL), was measured to indicate relative Al stress response using a hydroponic system in a 3 μM Al solution at pH 4.5. A diallel analysis indicated the significance of general combining ability (gca) variance for RRL but not the specific combining ability (sca) variance; the same result was obtained for TRL but not for RL. For both RRL and TRL, genetic variance appeared to be more important than the environmental variance. For RRL, a strong but non-significant correlation was indicated between parental performance and their gca effects; while mid-parent heterosis and/or over-dominance were detected, as associated with the expressed sca effects in several combinations. These results suggest the complex genetic nature and expression of Al tolerance in the 4-parent diallel crossing system tested. Al-tolerant parent, GAAT‘S’, was the most promising parent, conferring the highest gca effects for RRL as well as for other two characters. The existence of significant gca variance in RRL may also suggest the feasibility of improving Al tolerance through enhanced root regrowth using phenotypic recurrent mass selection to pyramid desirable Al-tolerant genes, focussing on parental lines and/or elite individual plants expressing long regrowth roots.

The resistance of a diverse range of Trifolium species (clovers) to a highly virulent bluegreen aphid (BGA, Acyrthosiphon kondoi Shinji) population (Urrbrae 2011) collected in South Australia was assessed in greenhouse and field experiments, with the aims of determining the potential impact of this insect pest on biomass and identifying resistant genotypes for future plant-breeding activities. Resistance to BGA was found in populations of clovers that show some level of outcrossing—white clover (T. repens L.), rose clover (T. hirtum All.), crimson clover (T. incarnatum L.) and red clover (T. pratense L.)—and in one entry of the inbreeding subspecies of subterranean clover, T. subterraneum L. subsp. subterraneum (Katzn. and Morley). Resistance was not found in T. s. brachycalycinum (Katzn. and Morley) or T. s. yanninicum (Katzn. and Morley). In a greenhouse experiment, damage from BGA resulted in forage yield penalties of 72–100% when aphids were inoculated at 14 days after sowing and 13−74% when inoculated at 42 days after sowing, showing that in optimum conditions BGA can be a serious pest of clovers. Observations of severe damage caused by BGA in two regenerating field trials in southern New South Wales confirmed that field damage could occur in seasons favourable to aphid growth and reproduction. The severe damage that BGA can cause to clovers, and the sources of resistance we found, suggest that breeding for BGA resistance in clovers is warranted and feasible.

Plant germplasm, totalling 1,344 accessions, was collected during the course of two Australian led seed collection missions in Kazakhstan in 2002 and Azerbaijan in 2004. The collection in Kazakhstan involved members from Australia, China, the Vavilov Institute in Russia and the Aral Sea Experiment Station in Kazakhstan while the mission to Azerbaijan involved scientists from Australia, ICARDA and the Azerbaijan National Academy of Sciences.

In dryland Mediterranean environments, the productivity of annual legumes is low during autumn and winter, with plant senescence typically beginning by the middle of spring because of low soil water availability. Therefore, the use of deep-rooted perennial legumes may provide an alternative to annual legumes in regions with a soil moisture deficit. We evaluated the germplasm of new perennial legumes with deep rooting systems in two field experiments in the interior drylands of central Chile. In experiment 1, sixteen genotypes of four perennial legume species, nine cultivars (cvs.) of Medicago sativa , two of Hedysarum coronarium , three of Lotus tenuis , and two of Lotus corniculatus were evaluated for three seasons (2012-2014). In experiment 2, eight additional genotypes from two perennial legume species ( M. sativa and H. coronarium ) were evaluated between 2013 and 2015. Additionally, sixteen cultivars and accessions of M. sativa were evaluated in raised beds, with nine from Australia, two from Spain, two from California and three of Andean origin. We evaluated plant survival, nodulation, plant height at the end of the winter period and temporal distribution of biomass production. The persistence of M. sativa cultivars was high (over 80% survival after three years), but only the lucerne produced high yields (8-11 Mg ha -1 in the third season). Significant differences for winter production were detected among the lucerne cultivars, associated with their winter activity class, but no differences were found in total biomass production. The persistence of L. tenuis , L. corniculatus and H. coronarium was poor, and the biomass production was low, most likely because rhizobia failed to persist. Based on these preliminary results on perennial legumes, lucerne has great potential as a forage crop in the interior drylands of central Chile. However, more research on rhizobial strains, nodulation, plant growth and biomass accumulation, and root distribution and water use, among other factors, is required to better understand the persistence of perennial legumes in rain fed environments. En ambientes mediterraneos de secano, la productividad de leguminosas anuales es baja durante el otono y el invierno, y la senescencia tipicamente comienza a mediados de la primavera debido a la baja disponibilidad de agua en el suelo. Por lo tanto, el uso de leguminosas perennes con raices pivotantes profundas puede proporcionar una alternativa a las leguminosas anuales en las regiones con un deficit de humedad del suelo. Se evaluo el germoplasma de nuevas leguminosas perennes con sistemas de raices profundas en dos experimentos de campo en el secano interior de Chile central. En el experimento 1, se evaluaron dieciseis genotipos de cuatro especies de leguminosas perennes, nueve cultivares (cvs.) de Medicago sativa , dos de Hedysarum coronarium , tres de Lotus tenuis y dos de Lotus corniculatus , durante tres temporadas (2012-2014). En el experimento 2, se evaluaron ocho genotipos adicionales de dos especies de leguminosas perennes ( M. sativa y H. coronarium ) entre 2013 y 2015. Ademas, se evaluaron dieciseis cultivares y accesiones de M. sativa en bancadas, nueve de Australia, dos de Espana, dos de California y tres de origen andino. Se evaluo la supervivencia de la planta, la nodulacion, altura de la planta al final del periodo de invierno y distribucion temporal de la produccion de biomasa. La persistencia de cultivares de M. sativa fue alta (mas del 80% de supervivencia a los tres anos), pero solo la alfalfa produjo altos rendimientos (8-11 Mg ha -1 en la tercera temporada). Se detectaron diferencias significativas para la produccion de invierno entre los cultivares de alfalfa, lo que estuvo asociado a la clase de actividad de invierno, pero no se encontraron diferencias en la produccion total de biomasa. La persistencia de L. tenuis , L. corniculatus y H. coronarium fue pobre y la produccion de biomasa fue baja, muy probablemente porque los rizobios no pudieron persistir. Sobre la base de estos resultados preliminares obtenidos en leguminosas perennes, la alfalfa tiene un gran potencial como cultivo forrajero en el secano interior Chile central. Sin embargo, se requiere de mas investigacion acerca de las cepas de rizobios, nodulacion, crecimiento y acumulacion de biomasa, la distribucion de la raiz y el uso del agua, entre otros factores, para entender mejor la persistencia de las leguminosas perennes en ambientes de secano.

Trifolium tumens (Talish clover) is a perennial legume species not previously domesticated for use in world agriculture. It is native to areas of the eastern Mediterranean, Caucasus and mountainous areas of the Middle East with a warm temperate or cool Mediterranean environment. The species has been identified by pasture researchers in Australia as a having sufficient drought and grazing tolerance to fill a gap created by the lack of a well adapted perennial legume for dryland pasture systems across low rainfall (450 to 750 mm annual average rainfall), temperate regions of Australia. The need to expand available genetic diversity of this species resulted in a germplasm collecting mission to Azerbaijan in 2004. The successful mission collected seed from 35 populations of T. tumens across 7 agro ecological zones, including 5 climatic zones. This collection increased the number of accessions held in ex situ local and international collections from 21 to 56. The range of adaptation and frequency of the collection of T. tumens was far greater than expected with accessions found at altitudes ranging from 12 to 1700 m above sea level, in soils with pH (1:5 H20) ranging between 5.0 and 9.0 and rainfall varying from 300 to 1300 mm. T. tumens was found growing alongside a diverse range of companion species in heavily grazed lowland pastures up to lightly grazed alpine meadows. This material has been characterised by the Tasmanian Institute of Agriculture (TIA), with promising accessions contributing to a breeding program to develop a commercial cultivar adapted to temperate environments (

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.

Genotype by environmental interactions in lucerne (Medicago sativa L.) present considerable challenges when selecting an appropriate cultivar for a particular location and farming system. Data on the yield and persistence of a range of lucerne cultivars and experimental lines grown in two Tasmanian environments, Forth (41.20°S, 146.27°E, Red Ferrosol soil, under cutting with high fertiliser inputs, i.e. a high yield potential environment) and Cranbook (42.00°S, 148.03°E, Red Ferrosol soil, under grazing with low fertiliser inputs, i.e. a low yield potential environment) were examined using winter activity class as the experimental factor. At Forth, winter-dormant lucernes were the lowest yielding genotypes. In contrast, at Cranbrook, highly winter-active genotypes had lower plant persistence and dry matter yield than winter-dormant genotypes. Modified joint linear regression analysis showed that in a cool temperate climate, winter-dormant genotypes are more suited to a low yield potential environment, whereas highly winter-active genotypes are adapted to a high yield potential environment. Both the semi-winter-dormant and the winter-active genotypes were adapted to all environments. The dry matter yield of winter-dormant and highly winter-active genotypes was most sensitive to environmental conditions in winter and spring, while performance of all cultivars and experimental lines was most stable over summer.