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Circumscription of the large genus Pultenaea Sm. has been contentious since shortly after description. We draw on recently generated phylogenomic data to provide a fully resolved phylogeny of Pultenaea and related genera based on near-complete species level sampling for the genus. Phylogenomic data divide Pultenaea sens. lat. into five independent lineages, corresponding to previously identified clades, that we recognise as distinct genera. Pultenaea sens. str. contains most of the currently recognised species and as circumscribed here, all of the species are endemic to eastern Australia except for P. tenuifolia R.Br. & Sims that extends across the Nullarbor into Western Australia. The genus Euchilus R.Br. is reinstated for eight species, all endemic to south-west Western Australia except for E. elachistus (F.Muell.) R.L.Barrett & Orthia that also occurs in South Australia. Three new genera are described, with all of the constituent species endemic to south-west Western Australia: Grievea R.L.Barrett, Clugston & Orthia, with two species, Jennata R.L.Barrett, Clugston & Orthia, with nine species and Loricobbia R.L.Barrett, Clugston & Orthia with six species. Pultenaea adunca Turcz. remains unplaced but we exclude this species from our concept of Pultenaea. Twenty-one new combinations are made: Euchilus aridus (E.Pritz.) R.L.Barrett & Orthia, E. calycinus subsp. proxenus (Orthia & Chappill) Orthia & R.L.Barrett, E. daena (Orthia & Chappill) Orthia & R.L.Barrett, E. elachistus (F.Muell.) R.L.Barrett & Orthia, Grievea brachytropis (Benth. ex Lindl.) R.L.Barrett & Orthia, G. craigiana (C.F.Wilkins, Orthia & Crisp) Orthia & R.L.Barrett, Jennata brachyphylla (Turcz.) R.L.Barrett & Clugston, J. empetrifolia (Meisn.) R.L.Barrett & Clugston, J. ericifolia (Benth.) R.L.Barrett & Clugston, J. indira (Orthia & Crisp) Orthia & R.L.Barrett, J. indira subsp. monstrosita (Orthia) Orthia & R.L.Barrett, J. indira subsp. pudoides (Orthia) Orthia & R.L.Barrett, J. radiata (H.B.Will.) R.L.Barrett & Clugston, J. strobilifera (Meisn.) R.L.Barrett & Clugston, J. verruculosa (Turcz.) R.L.Barrett & Clugston, Loricobbia aspalathoides (Meisn.) R.L.Barrett & T.D.Macfarl., L. ochreata (Meisn.) R.L.Barrett & T.D.Macfarl., L. pauciflora (M.B.Scott) R.L.Barrett & T.D.Macfarl., L. pinifolia (Meisn.) R.L.Barrett & T.D.Macfarl., L. reticulata (Sm.) R.L.Barrett & T.D.Macfarl. and L. skinneri (F.Muell.) R.L.Barrett & T.D.Macfarl. The bush-pea genus (Pultenaea) is one of the larger legume genera in Australia but has been difficult to define. We present a new classification of the group, recognising five genera instead of one using a large DNA based analysis of relationships. Three genera are newly described and one genus is reinstated, and these are almost entirely restricted to south-west Western Australia, with true Pultenaea being mostly restricted to eastern Australia. (Photograph by Russell Barrett.) This article belongs to the collection Genomics for Australian Plants. [ABSTRACT FROM AUTHOR]

Australia's 2019–2020 'Black Summer' bushfires burnt more than 8 million hectares of vegetation across the south-east of the continent, an event unprecedented in the last 200 years. Here we report the impacts of these fires on vascular plant species and communities. Using a map of the fires generated from remotely sensed hotspot data we show that, across 11 Australian bioregions, 17 major native vegetation groups were severely burnt, and up to 67–83% of globally significant rainforests and eucalypt forests and woodlands. Based on geocoded species occurrence data we estimate that >50% of known populations or ranges of 816 native vascular plant species were burnt during the fires, including more than 100 species with geographic ranges more than 500 km across. Habitat and fire response data show that most affected species are resilient to fire. However, the massive biogeographic, demographic and taxonomic breadth of impacts of the 2019–2020 fires may leave some ecosystems, particularly relictual Gondwanan rainforests, susceptible to regeneration failure and landscape-scale decline. Fires triggered by climate change threaten plant diversity in many biomes. Here the authors investigate how the catastrophic fires of 2019–2020 affected the vascular flora of SE Australia. They report that 816 species were highly impacted, including taxa of biogeographic and conservation interest. [ABSTRACT FROM AUTHOR]

The Senecioneae are one of the largest tribes of Asteraceae, with more than 3000 species and a global distribution. They also contain a large number of invasive species such as fireweed (Senecio madagascariensis), cape ivy (Delairea odorata), and ragwort (Jacobaea vulgaris). Although sequence data are available for many species, published phylogenies are for the most part restricted to specific subgroups, and the most broadly sampled phylogenies have limited coverage in depth. Fifty‐two of 126 native Australian or introduced species remain unsequenced. As a consequence, the phylogenetic relationships of introduced and native Australian taxa remain difficult to assess, hampering research in biocontrol. We inferred ribosomal and chloroplast phylogenies of the Senecioneae incorporating all available data for the four most frequently sequenced gene regions (nrITS, nrETS, psbA‐trnH, trnL) and generated sequence data for 32 additional species to inform the assembly of biocontrol test lists. Our results indicate that nine newly sequenced species currently classified as Senecio are phylogenetically distant from that genus. Although initially unexpected, the inferred affiliations of eight of these species are also supported by morphology, biogeography and chromosome numbers, together providing strong evidence in favour of taxonomic changes. Three species are added to previously phylogenetically isolated and monotypic Lordhowea, and the new genus Scapisenecio is created to accommodate five species characterised by a rosette habit with scapose capitulescences occurring in alpine to subalpine habitats of southeastern Australia. [ABSTRACT FROM AUTHOR]

Paterson’s curse (Echium plantagineum L. (Boraginaceae)), is an herbaceous annual native to Western Europe and northwest Africa. It has been recorded in Australia since the 1800’s and is now a major weed in pastures and rangelands, but its introduction history is poorly understood. An understanding of its invasion pathway and subsequent genetic structure is critical to the successful introduction of biological control agents and for provision of informed decisions for plant biosecurity efforts. We sampled E. plantagineum in its native (Iberian Peninsula), non-native (UK) and invaded ranges (Australia and South Africa) and analysed three chloroplast gene regions. Considerable genetic diversity was found among E. plantagineum in Australia, suggesting a complex introduction history. Fourteen haplotypes were identified globally, 10 of which were co-present in Australia and South Africa, indicating South Africa as an important source population, likely through contamination of traded goods or livestock. Haplotype 4 was most abundant in Australia (43%), and in historical and contemporary UK populations (80%), but scarce elsewhere (< 17%), suggesting that ornamental and/or other introductions from genetically impoverished UK sources were also important. Collectively, genetic evidence and historical records indicate E. plantagineum in southern Australia exists as an admixture that is likely derived from introduced source populations in both the UK and South Africa. [ABSTRACT FROM AUTHOR]

Invasive grass weeds reduce farm productivity, threaten biodiversity, and increase weed control costs. Identification of invasive grasses from native grasses has generally relied on the morphological examination of grass floral material. DNA barcoding may provide an alternative means to identify co-occurring native and invasive grasses, particularly during early growth stages when floral characters are unavailable for analysis. However, there are no universal loci available for grass barcoding. We herein evaluated the utility of six candidate loci (atpF intron, matK, ndhK-ndhC, psbE—petL, ETS and ITS) for barcode identification of several economically important invasive grass species frequently found among native grasses in eastern Australia. We evaluated these loci in 66 specimens representing five invasive grass species (Chloris gayana, Eragrostis curvula, Hyparrhenia hirta, Nassella neesiana, Nassella trichotoma) and seven native grass species. Our results indicated that, while no single locus can be universally used as a DNA barcode for distinguishing the grass species examined in this study, two plastid loci (atpF and matK) showed good distinguishing power to separate most of the taxa examined, and could be used as a dual locus to distinguish several of the invasive from the native species. Low PCR success rates were evidenced among two nuclear loci (ETS and ITS), and few species were amplified at these loci, however ETS was able to genetically distinguish the two important invasive Nassella species. Multiple loci analyses also suggested that ETS played a crucial role in allowing identification of the two Nassella species in the multiple loci combinations. [ABSTRACT FROM AUTHOR]

Cucumis myriocarpus is an annual cucurbitaceous summer weed infesting fallow fields and pastures. Infestation results in reduced moisture availability for winter cereal crops as well as reduced crop yields and pasture quality. The need to manage this weed is of paramount importance given its adverse effects on farming systems, biodiversity and grazing livestock and its ranking as the number one weed of importance in Australian summer fallows of grain crops. Land management practices, including movement of grazing animals and over-stocking, are potentially assisting the spread of Cucumis myriocarpus fruits and viable seed. The plant is characterized by the presence of small, ellipsoid to spherical melon fruits with spiny appendages. Each plant can produce up to 50 or more melons per plant, with each fruit containing up to 200 viable seeds. Seed is often dormant upon fruit maturity and our results under controlled environmental conditions suggest both physiological and physical factors influence dormancy. Under field conditions, seedlings can form large vines growing upto 3 m in length. Field pollination experiments suggest that this melon is mainly self-pollinated by insects, including bees, flies and wasps. Cucumis myriocarpus is generally managed by the use of various broadleaf phenoxy herbicides and systemic post-emergent products. It is found in this study that this weed established through multiple flushes of germination, hence multiple herbicidal applications coinciding with rainfall events one suggested for more efficacious management. However, rotation of infested pastures with cereal crops such as canola and wheat also results in improved control. Additional studies into the impact of soil with and physical properties, disturbance and grazing, are recommended for development of more efficacious control measures. This review discusses taxonomy, genetic variation, biology and ecology and management of this important summer annual weed. [ABSTRACT FROM AUTHOR]

A general prediction of ecological theory is that climate change will favor invasive nonindigenous plant species (NIPS) over native species. However, the relative fitness advantage enjoyed by NIPS is often affected by resource limitation and potentially by extreme climatic events such as drought. Genetic constraints may also limit the ability of NIPS to adapt to changing climatic conditions. In this study, we investigated evidence for potential NIPS advantage under climate change in two sympatric perennial stipoid grasses from southeast Australia, the NIPS Nassella neesiana and the native Austrostipa bigeniculata. We compared the growth and reproduction of both species under current and year 2050 drought, temperature and CO2 regimes in a multifactor outdoor climate simulation experiment, hypothesizing that NIPS advantage would be higher under more favorable growing conditions. We also compared the quantitative variation and heritability of growth traits in populations of both species collected along a 200 km climatic transect. In contrast to our hypothesis we found that the NIPS N. neesiana was less responsive than A. bigeniculata to winter warming but maintained higher reproductive output during spring drought. However, overall tussock expansion was far more rapid in N. neesiana, and so it maintained an overall fitness advantage over A. bigeniculata in all climate regimes. N. neesiana also exhibited similar or lower quantitative variation and growth trait heritability than A. bigeniculata within populations but greater variability among populations, probably reflecting a complex past introduction history. We found some evidence that additional spring warmth increases the impact of drought on reproduction but not that elevated atmospheric CO2 ameliorates drought severity. Overall, we conclude that NIPS advantage under climate change may be limited by a lack of responsiveness to key climatic drivers, reduced genetic variability in range-edge populations, and complex drought-CO2 interactions. [ABSTRACT FROM AUTHOR]

We investigated some of the factors influencing exotic invasion of native sub-alpine plant communities at a site in southeast Australia. Structure, floristic composition and invasibility of the plant communities and attributes of the invasive species were studied. To determine the plant characteristics correlated with invasiveness, we distinguished between roadside invaders, native community invaders and non-invasive exotic species, and compared these groups across a range of traits including functional group, taxonomic affinity, life history, mating system and morphology. Poa grasslands and Eucalyptus-Poa woodlands contained the largest number of exotic species, although all communities studied appeared resilient to invasion by most species. Most community invaders were broad-leaved herbs while roadside invaders contained both herbs and a range of grass species. Over the entire study area the richness and cover of native and exotic herbaceous species were positively related, but exotic herbs were more negatively related to cover of specific functional groups (e.g. trees) than native herbs. Compared with the overall pool of exotic species, those capable of invading native plant communities were disproportionately polycarpic, Asteracean and cross-pollinating. Our data support the hypothesis that strong ecological filtering of exotic species generates an exotic assemblage containing few dominant species and which functionally converges on the native assemblage. These findings contrast with those observed in the majority of invaded natural systems. We conclude that the invasion of closed sub-alpine communities must be viewed in terms of the unique attributes of the invading species, the structure and composition of the invaded communities and the strong extrinsic physical and climatic factors typical of the sub-alpine environment. [ABSTRACT FROM AUTHOR]

Australia has a very diverse pea-flowered legume flora with 1715 native and naturalised species currently recognised. Tribe Mirbelieae s.l. includes 44% of Australia's peas in 24 genera with 756 recognised species. However, several genera within the Pultenaea alliance in tribe Mirbelieae are considered to be non-monophyletic and two main options have been proposed: option one is to merge ca. 18 genera containing ca. 540 species (the largest genus, Pultenaea has nomenclatural priority); and option two is to re-circumscribe some genera and describe new genera as required to form monophyletic groups. At the species level, option one would require 76% of names to be changed; whereas based on available data, option two is likely to require, at most, 8.3% of names to change. Option two therefore provides the least nomenclatural disruption but cannot be implemented without a robust phylogenetic framework to define new generic limits. Here we present novel analyses of available plastid DNA data (trnL-F) which suggest that option two would be feasible once sufficient data are generated to resolve relationships. However, the reticulate evolutionary histories or past rapid speciation suggested for this group may prevent the resolution of all nodes. We propose targeted use of Next-Generation Sequencing technology as the best way to resolve relationships between the key clades in the tribe and present a framework for such a study. An overview of current taxonomy in the tribe is presented, along with the state of taxonomic knowledge and availability of published descriptions for electronic flora treatments. Several new combinations and typifications are published in an appendix. [ABSTRACT FROM AUTHOR]

The Australian Plant Name Index (APNI), is a comprehensive database of published names of Australian vascular plants, now available on-line at: www.anbg.gov.au/apni. The International Code of Botanical Nomenclature has strict rules on the publication and priority of plant names and must be very carefully considered in any revision involving new plant names and name changes. In Australia we have an enormous heritage of taxonomic literature in many languages and from many sources, and much of this literature is not readily available either here or overseas. To assist clients needing this information, the Australian Academy of Science Standing Committee for a Flora of Australia set up the Australian Plant Name Index project in 1973, supervised by Nancy T. Burbidge AM (1912-77). The first compiler was Penelope Hack, succeeded in 1974 by Arthur D. Chapman, but a number of botanists assisted especially during the early years. A four-volume, hard copy edition was published by the Australian Biological Resources Study [ABRS ] in 1991 ((Chapman, 1991). This contained the bibliographic and typification details for more than 60,000 Australian plant names. [ABSTRACT FROM AUTHOR]

We introduce the AusTraits database - a compilation of values of plant traits for taxa in the Australian flora (hereafter AusTraits). AusTraits synthesises data on 448 traits across 28,640 taxa from field campaigns, published literature, taxonomic monographs, and individual taxon descriptions. Traits vary in scope from physiological measures of performance (e.g. photosynthetic gas exchange, water-use efficiency) to morphological attributes (e.g. leaf area, seed mass, plant height) which link to aspects of ecological variation. AusTraits contains curated and harmonised individual- and species-level measurements coupled to, where available, contextual information on site properties and experimental conditions. This article provides information on version 3.0.2 of AusTraits which contains data for 997,808 trait-by-taxon combinations. We envision AusTraits as an ongoing collaborative initiative for easily archiving and sharing trait data, which also provides a template for other national or regional initiatives globally to fill persistent gaps in trait knowledge., (© 2021. The Author(s).)