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The tomato potato psyllid, Bactericera cockerelli Šulc, originating from North and Central America, poses a serious threat to Solanaceae crops in Australia. This study investigates the potential of the Australian native and commercially available green lacewing, Mallada signatus Schneider, as a biological control agent for B. cockerelli. The effect of feeding on B. cockerelli on the development rate and survival, of M. signatus were evaluated. Further, a greenhouse cage study was conducted to determine the optimal density of M. signatus larvae needed to effectively control an established B. cockerelli population. In our study, the third instar larvae of M. signatus consumed over 75 B. cockerelli nymphs in 24 h. Following the introduction of M. signatus larvae to caged tomato plants, eight M. signatus larvae per caged tomato plant decreased B. cockerelli population by 64% at the end of the sampling. These results indicated M. signatus, particularly at the larval stage, is an effective biological control option for B. cockerelli, especially in greenhouse tomato cultivation. This research offers valuable insights for the Australian horticultural industry, presenting a viable, eco‐friendly alternative to traditional, chemical pesticide‐reliant pest management strategies. [ABSTRACT FROM AUTHOR]

Simple Summary: The tomato potato psyllid, Bactericera cockerelli, is an important insect pest of potato, tomato, and other solanaceous crops. B. cockerelli was first detected on mainland Australia in Perth, Western Australia, in early 2017, which poses a major threat to Australian vegetable industries. It damages directly by feeding and indirectly as a vector of Candidatus Liberibacter solanaceaerum (CLso) that causes zebra chip disease in potatoes. Thus far, B. cockerelli has not been reported in other states of Australia. As B. cockerelli has been reported resistant to insecticides in USA and Mexico, biological control with native natural enemies may provide a viable alternative strategy to manage the insect. In this review, we begin with an overview of information on B. cockerelli, its incursion into Australia, and its impact on crops and current management. Opportunities to develop biological control strategies to alleviate the dependence on synthetic insecticides are also considered in this review. Moreover, the potential of existing natural enemies to contribute toward regulating populations of B. cockerelli in the field and the challenges ahead to strengthen the key role they can play through conservation biological control are also discussed. Incursion and establishment of an exotic pest may threaten natural habitats and disrupt ecosystems. On the other hand, resident natural enemies may play an important role in invasive pest control. Bactericera cockerelli, commonly known as the tomato-potato psyllid, is an exotic pest, first detected on mainland Australia in Perth, Western Australia, in early 2017. B. cockerelli causes direct damage to crops by feeding and indirectly by acting as the vector of the pathogen that causes zebra chip disease in potatoes, although the latter is not present in mainland Australia. At present, Australian growers rely on the frequent use of insecticides to control B. cockerelli, which may lead to a series of negative economic and environmental consequences. The incursion of B. cockerelli also provides a unique opportunity to develop a conservation biological control strategy through strategically targeting existing natural enemy communities. In this review, we consider opportunities to develop biological control strategies for B. cockerelli to alleviate the dependence on synthetic insecticides. We highlight the potential of existing natural enemies to contribute toward regulating populations of B. cockerelli in the field and discuss the challenges ahead to strengthen the key role they can play through conservation biological control. [ABSTRACT FROM AUTHOR]

Premise: Whole‐genome duplication is considered a major mechanism of sympatric speciation due to the creation of strong and instantaneous reproductive barriers. Although postzygotic reproductive isolation between diploids and polyploids is often expected, the extent of reproductive incompatibility must be empirically determined and compared to patterns of genetic isolation to fully characterize the reproductive dynamics between cytotypes. Methods: We investigated reproductive compatibility between diploid and tetraploid Lycium australe in two mixed‐cytotype populations using (1) controlled crossing experiments to evaluate fruit and seed production and (2) germination trials to test seed viability following homoploid and heteroploid crosses. We contrast these experiments with a single‐nucleotide polymorphism (SNP) data set to measure genetic isolation between cytotypes and explore whether cytotype or population origin better explains patterns of genetic variation. Finally, we explore mating patterns using the observed germination rates of naturally produced seeds in each population. Results: Although homoploid and heteroploid crosses resulted in similar fruit and seed production, reproductive isolation between co‐occurring diploids and tetraploids was nearly complete, due to low seed viability following heteroploid crosses. Of 191,182 total SNPs, 21,679 were present in ≥90% of individuals and replicate runs using unlinked SNPs revealed strong clustering by cytotype and differentiation of tetraploids based on population origin. Conclusions: As often reported, diploid and tetraploid L. australe experience strong postzygotic isolation via hybrid seed inviability. Consistent with this result, cytotype explained a greater amount of variation in the SNP data set than population origin, despite some evidence of historical introgression. [ABSTRACT FROM AUTHOR]

Background and Aims The extent to which genome size and chromosome numbers evolve in concert is little understood, particularly after polyploidy (whole-genome duplication), when a genome returns to a diploid-like condition (diploidization). We study this phenomenon in 46 species of allotetraploid Nicotiana section Suaveolentes (Solanaceae), which formed <6 million years ago and radiated in the arid centre of Australia. Methods We analysed newly assessed genome sizes and chromosome numbers within the context of a restriction site-associated nuclear DNA (RADseq) phylogenetic framework. Key Results RADseq generated a well-supported phylogenetic tree, in which multiple accessions from each species formed unique genetic clusters. Chromosome numbers and genome sizes vary from n = 2x = 15 to 24 and 2.7 to 5.8 pg/1C nucleus, respectively. Decreases in both genome size and chromosome number occur, although neither consistently nor in parallel. Species with the lowest chromosome numbers (n = 15–18) do not possess the smallest genome sizes and, although N. heterantha has retained the ancestral chromosome complement, n = 2x = 24, it nonetheless has the smallest genome size, even smaller than that of the modern representatives of ancestral diploids. Conclusions The results indicate that decreases in genome size and chromosome number occur in parallel down to a chromosome number threshold, n = 20, below which genome size increases, a phenomenon potentially explained by decreasing rates of recombination over fewer chromosomes. We hypothesize that, more generally in plants, major decreases in genome size post-polyploidization take place while chromosome numbers are still high because in these stages elimination of retrotransposons and other repetitive elements is more efficient. Once such major genome size change has been accomplished, then dysploid chromosome reductions take place to reorganize these smaller genomes, producing species with small genomes and low chromosome numbers such as those observed in many annual angiosperms, including Arabidopsis. [ABSTRACT FROM AUTHOR]

A new species of functionally dioecious bush tomato of Solanum subgenus Leptostemonum is described. Solanum scalarium Martine & T.M.Williams, sp. nov., is a member of the taxonomically challenging "Kimberley dioecious clade" in Australia and differs from other species in the group in its spreading decumbent habit and conspicuously prickly male floral rachis. The species is so far known from one site in Judbarra/Gregory National Park in the Northern Territory. Ex situ crosses and confirmation of inaperturate pollen grains produced in morphologically cosexual flowers indicate that these flowers are functionally female and the species is functionally dioecious. The scientific name reflects the ladder-like appearance of the inflorescence rachis armature of male individuals, the stone staircase that provides access to the type locality at the Escarpment Lookout Walk, and the importance of maintaining equitable and safe access to outdoor spaces. The common name Garrarnawun Bush Tomato is proposed in recognition of the lookout point at this site, a traditional meeting place of the Wardaman and Nungali-Ngaliwurru peoples whose lands overlap in this area. [ABSTRACT FROM AUTHOR]

Nicotiana benthamiana is an indigenous plant species distributed across northern Australia. The laboratory accession (LAB) of N. benthamiana has become widely adopted as a model host for plant viruses, and it is distinct from other accessions morphologically, physiologically, and by having an attenuation-of-function mutation in the RNA-dependent RNA polymerase 1 (NbRdr1) gene, referred to as NbRdr1m. Recent historical evidence suggested LAB was derived from a 1936 collection by John Cleland at The Granites of the Northern Territory, although no scientific evidence was provided. We provide scientific evidence and further historical evidence supporting the origin of LAB as The Granites. Analysis of a herbarium specimen of N. benthamiana collected by Cleland in 1936 revealed that The Granites population contains plants heterozygous for the NbRdr1 locus, having both the functional NbRdr1 and the mutant NbRdr1m alleles. N. benthamiana was an important cultural asset actively utilised as the narcotic Pituri (chewing tobacco) by the Warlpiri Aboriginal people at the site, who prevented women of child-bearing age from consuming it. We propose that Aboriginal people selected some of the unique traits of LAB that have subsequently facilitated its adoption as a model plant, such as lack of seed dormancy, fast maturity, low nornicotine content, and gracility. [ABSTRACT FROM AUTHOR]

Summary: In this volume of Curtis's Botanical Magazine, we increase the number of species recognised in Nicotiana sect. Suaveolentes to 38, up from the 21 recorded in the Flora of Australia published 39 years ago, but we estimate the final number is likely to exceed 60. We examine the reasons why so many unrecognised species exist. Several Australian and American botanists have previously specialised in Nicotiana but did not detect such diversity. We have carried out many fieldtrips, seen most known species in the wild and have grown these accessions from diverse areas side‐by‐side in cultivation to avoid basing decisions about species characteristics on features heavily influenced by environmental plasticity. In the end, we conclude that it is a mixture of focused and extensive fieldwork and more recent genomic, genetic and karyological studies combined in the process of reciprocal illumination, that has enabled us to describe so many new species. We also briefly focus on the topic of why Nicotiana is so species‐rich in Australia. [ABSTRACT FROM AUTHOR]

Explosive radiations—substantial increases in net species diversification—have been considered one of the most intriguing diversification patterns across the Tree of Life, but the subsequent change, movement, and extinction of the constituent lineages make radiations hard to discern or understand as geological time passes. We used the megadiverse angiosperm genus Solanum L. (Solanaceae), with ca. 1200 currently accepted species distributed worldwide in a wide array of habitats, to explore these patterns on a global scale. We synthesized phylogenetic and distributional data for this ongoing radiation to show how dispersal events and past climatic changes have interacted to shape diversification. We find that, despite the vast diversity of Solanum lineages in the Neotropics, lineages in the Old World are diversifying more rapidly. This recent increase in diversification coincides with a long‐distance dispersal event from the Neotropics to regions where major climatic changes were taking place. Two separate groups of Solanum have migrated and established in Australia, but only the arid‐adapted lineages underwent significant increases in diversification rate, as they were able to adapt to the continent's long‐term climatic trend towards seasonally dry and arid biomes (a pattern observed in the diversification of other arid‐adapted groups). Our findings provide a clear example of how successful colonization of new areas and niches can—but does not always—drive explosive diversifications. [ABSTRACT FROM AUTHOR]

Nicotiana section Suaveolentes is the largest section of Nicotiana and is a monophyletic group of allotetraploid species. Most of the species are endemic to Australia, but three species occur on islands in the South Pacific as far east as French Polynesia and one species is native to Namibia. Here, we present phylogenetic results based on genome skimming, with near-complete taxon sampling and multiple accessions sampled for several species. These represent the first phylogenetic results for the section that include most recognized taxa, using wild-sourced material wherever possible. Despite known chromosome number and genome size changes in the section, there is little divergence in the ribosomal DNA operon (26S, 18.S and 5.8S plus associated spacers) and plastid genomes, with little to no taxonomic signal in plastome phylogenetic results and clear plastid-nuclear discordance. These results contrast with strong morphological differentiation (both floral and vegetative) between most of the core Australian taxa and obvious differences in ecological preferences. Together, these initial results portray Nicotiana section Suaveolentes as experiencing recent and ongoing radiation in the arid zone of Australia. [ABSTRACT FROM AUTHOR]

A bush tomato that has evaded classification by solanologists for decades has been identified and is described as a new species belonging to the Australian "Solanum dioicum group" of the Ord Victoria Plain biogeographic region in the monsoon tropics of the Northern Territory. Although now recognised to be andromonoecious, S. plastisexum Martine & McDonnell, sp. nov. exhibits multiple reproductive phenotypes, with solitary perfect flowers, a few staminate flowers or with cymes composed of a basal hermaphrodite and an extended rachis of several to many staminate flowers. When in fruit, the distal rachis may abcise and drop. A member of Solanum subgenus Leptostemonum, Solanum plastisexum is allied to the S. eburneum Symon species group. Morphometric analyses presented here reveal that S. plastisexum differs statistically from all of its closest relatives including S. eburneum, S. diversiflorum F. Meull., S. jobsonii Martine, J.Cantley & L.M.Lacey, S. succosum A.R.Bean & Albr. and S. watneyi Martine & Frawley in both reproductive and vegetative characters. We present evidence supporting the recognition of S. plastisexum as a distinctive entity, a description of the species, representative photographs, a map showing the distribution of members of the S. eburneum species group and a key to the andromonoecious Solanum species of the Northern Territory of Australia. This new species is apparently labile in its reproductive expression, lending to its epithet, and is a model for the sort of sexual fluidity that is present throughout the plant kingdom. [ABSTRACT FROM AUTHOR]

Solanum elaeagnifolium Cav. is a widely distributed weed and recognized as a Weed of National Significance in Australia. This study sequenced the chloroplast (cp) genome of S. elaeagnifolium, which is 155,049 bp in length, including a large single-copy region at 85, 426 bp, a small single-copy region at 18,419 bp and two inverted repeats at 25,602 bp. A total of 130 genes were annotated. The phylogeny among the S. elaeagnifolium and 42 Solanum chloroplast genomes suggested S. elaeagnifolium is closely related to Solanum species from the section of Melongena. [ABSTRACT FROM AUTHOR]

Solanum elaeagnifolium Cav. is considered as one of the worst weeds of crop and pasture systems in temperate Australia. Effective long-term control is difficult due to the extensive root system. Field experiments were conducted at two locations in south-eastern Australia between 2006 and 2008 to examine a range of herbicides for control of S. elaeagnifolium on seed production and root regrowth. Herbicide performance was affected by herbicide, weed growth stage and environmental factors. Pyridine herbicides, such as pre-packed mixtures of aminopyralid + fluroxypyr and triclopyr + picloram + aminopyralid were the most effective and consistently reduced within-season aerial growth by 60–90% in both seasons. Overall control using glyphosate-based treatments was generally reduced due to emergence of new stems following herbicide application. Three picloram-based treatments provided the best and most consistent long-term control on root regrowth after two seasons, reducing stem emergence by 45–88%, especially with a late application of herbicides. The efficacy of residual herbicides such as atrazine or imazapic + imazapyr depends on rainfall conditions. Seedset control was best achieved with herbicides applied at the start of flowering stage, with no viable seed produced following treatments of 2,4-D amine + picloram and triclopyr + picloram + aminopyralid. These two treatments also significantly reduced viable seed production when applied at the early berry stage. The results indicate that an application at early flowering followed by a late application in autumn is necessary to effectively control the seedset (seedbank) and the root regrowth (rootbank) of S. elaeagnifolium . [ABSTRACT FROM AUTHOR]

In present study, we report the complete chloroplast genome of Nicotiana debneyi, a species endemic to eastern coast of Australia. The total genome size of N.debneyi is 156,073 bp in length, containing a large single-copy region of 86,672 bp, a small single-copy region of 18,581 bp, and two inverted repeat regions of 25,410 bp. The all GC content of N.debneyi chloroplast genome is 38.4%. It encodes a total of 129 unique genes, including 84 protein-coding genes, 37 tRNA genes, and eight rRNA genes, of which seven tRNA, four rRNA and seven protein-coding genes are duplicated in the IR. Sixteen genes contain a single intron, and only two genes have two introns. Phylogenetic analysis results strongly supported that N.debneyi was closely related to Nicotiana sylvestris and Nicotiana tabacum. [ABSTRACT FROM AUTHOR]

Pituri (Duboisia hopwoodii (F. Muell.) F. Muell.) (Solanaceae) is a narcotic shrub which grows in the parallel dune fields of the Simpson Desert of far south-western Queensland, Australia. The ethnographic literature points to an impressive scale of trade of pituri between Aboriginal groups across inland eastern Australia, and suggests total annual production of 2500-3000 kg of dried plant material. However, there has been no attempt to assess the feasibility of these figures, or investigate the number of pituri plants required to sustain such a scale of trade. We mapped the distribution and density of D. hopwoodii along four one km wide transects, totally 130 km in length. Our results suggest that the population of pituri west of the Mulligan River could number around 36,000 mature plants. Ninety randomly selected plants were measured, and the foliage of six of these was harvested and dried. Plants yielded between 0.15 and 6.68 kg of dry matter. Our 90 measured plants would have yielded around 155 kg of dried pituri. Therefore, between 1450 and 1740 plants would be required to sustain the purported level of trade and use. With knowledge of the location of dense pituri groves and highly efficient expeditions, harvesting this number of plants is feasible. However, numerous questions remain surrounding the ecological and ethnographic aspects of the pituri trade. [ABSTRACT FROM AUTHOR]

Aim Nicotiana section Suaveolentes is largely endemic to Australia but includes one species endemic to Africa, one to New Caledonia and Tongatupa, and one to the Marquesas Islands in the Pacific. Other sections of Nicotiana are found in the New World. In Australia, Suaveolentes is widespread across the continent, with many taxa adapted to the Eremean zone. We aim to analyse the biogeography of the Australian clade, both to shed light on the evolution of the group and to determine general area relationships that provide insight into the history of the arid-zone biota. Location Mesic and arid regions of continental Australia, the Central-South Pacific and Namibia, Africa. Methods A phylogeny of Suaveolentes, based on morphology and molecular data, was used to analyse the relationships of areas in which the taxa occur. The section is monophyletic, and all but three taxa were included (25). The method of paralogy-free subtree analysis was employed, with the basal taxon Nicotiana africana used as the outgroup. Results Paralogy-free subtree analysis found five area subtrees that, when combined, resulted in a minimal area cladogram with six resolved nodes. Pacific and mesic eastern Australia (including Lord Howe Island) are at the base of the area cladogram, followed by the differentiation of North West Australia and later South East Australia. Arid regions of Australia are related, revealing three biogeographical tracks: a northern track including the Great Sandy Desert and Tanami, which are related to the Pilbara; a central track relating the Western Desert, Central Ranges, Eastern Desert and North East Interzone; and a southern track relating the South West Interzone, Nullarbor, Adelaide/Eyre and the South East Interzone. Plesiomorphic taxa with chromosome number n = 24-23 occur on the periphery of the continent, and derived taxa with n = 21, 20, 18, 16-15 identify the tracks across arid Australia. Main conclusions The patterns of distribution and differentiation of Suaveolentes in Australia show that the age of the clade is at least Early Miocene, dating to before the onset of aridification in Australia about 15 Ma. The patterns are also interpreted as evidence that it was vicariance that largely shaped speciation in the Eremean zone, with range expansion of some widespread taxa probably occurring in the most recent cycles of severe drying and mobilization of desert dune sands. [ABSTRACT FROM AUTHOR]

Molecular phylogenies alone have failed to resolve evolutionary relationships of Nicotiana L. section Suaveolentes Goodsp. (Solanaceae), a section largely comprising Australian endemics. Comparative morphology of Suaveolentes is illustrated and characters, together with the chromosome number, coded for phylogenetic analysis. Morphological characters included discrete characters of seeds and trichomes studied by scanning electron and light microscopy, and gap-coded quantitative measurements of flowers and vegetative organs. These data were analysed using both maximum parsimony and splits network, and compared to and combined with molecular analyses based on published nuclear and chloroplast-DNA sequences. Among morphological characters, there was a high level of homoplasy, possibly attributable to convergent evolution, hybridisation and introgression, and the underlying polyploid origin of the group. There was some conflict between the morphological and molecular datasets; however, overall there was a level of concordance that identified a phylogenetic sequence of taxa that reflected a reduction in the chromosome number. With N. africana as the functional outgroup, analyses showed N. fragrans (New Caledonia and Tongatapu) and N. fatuhivensis (Marquesas islands, formerly N. fragrans var. fatuhivensis) to be a basal lineage in the Australian and South Pacific clade of Suaveolentes. N. forsteri (eastern mainland Australia, Lord Howe Island and New Caledonia) is the sister taxon to all other Australian species of Suaveolentes, which form a well supported monophyletic group. Within this Australian endemic group, species with a chromosome count of n = 24 or 23 are early lineages. Two clades with a reduced chromosome number are the 'N. simulans clade' (all taxa with n = 20) and the 'N. suaveolens clade' (n = 19, 18, 16, or 15). The position of N. cavicola (n = 20 or 23) is equivocal, and it and several other species require further study. Some widespread taxa require greater sampling of populations to test for variation in morphology, DNA sequences and chromosome number for further elucidation of the evolutionary history of Suaveolentes. [ABSTRACT FROM AUTHOR]

Two new species of Acizzia Heslop-Harrison (Hemiptera: Psyllidae) from the plant family Solanaceae in eastern Australia are described. Acizzia solanicola sp. n. can damage eggplant, Solanum melongena (Solanaceae), in commercial crops and gardens in eastern Australia. It is a new, potentially serious commercial pest species, of which the nymphs induce malformation of leaves, produce copious amounts of viscous waste and cause leaf wilting, premature leaf senescence and crop loss. These psyllids have a unique and characteristic method of disposing of honeydew and this is illustrated for the first time. Acizzia alternata sp. n. is recorded from the weed, wild tobacco bush, Solanum mauritianum, but appears to cause little damage. These comprise the first record of a pest psyllid on eggplant and the first record of Acizzia from the Solanaceae. The parasitoid, Psyllaephagus sp. (Hymenoptera: Encyrtidae), is recorded parasitising nymphs of A. solanicola sp. n., and is here proposed as a potential biological control agent against it. [ABSTRACT FROM AUTHOR]

Global climate change and anthropological activities have led to a decline in insect pollinators worldwide. Agricultural globalisation and intensification have also removed crops from their natural insect pollinators, and sparked research to identify alternate natural insect pollinators and artificial technologies. In certain countries such as Australia the importation of commercial insect pollinators is prohibited, necessitating manual labour to stimulate floral pollination. Artificial pollination technologies are now increasingly essential as the demand for food grown in protected facilities increases worldwide. For tomato fruits, precision pollination has the ability to vastly improve their seed set, size, yield, and quality under optimal environmental conditions and has become financially beneficial. Like many crops from the Solanaceae, tomatoes have a unique self-pollinating mechanism that requires stimulation of the floral organs to release pollen from the poricidal anthers. This review investigates various mechanisms employed to pollinate tomato flowers and discusses emerging precision pollination technologies. The advantages and disadvantages of various pollinating technologies currently available in the protected-cropping industry are described. We provide a buzz perspective on new promising pollination technologies involving robotic air and acoustic devices that are still in their nascency and could provide non-contact techniques to automate pollination for the tomato horticultural industry. [ABSTRACT FROM AUTHOR]

The recent decoding of a painting-by-numbers technique used in the Pacific over two hundred years ago has allowed the first complete portrayal in colour of a long-extinct island endemic, Solanum bauerianum Endl., restricted to Norfolk and Lord Howe Islands. [ABSTRACT FROM AUTHOR]

The pollination effectiveness of bluebanded bees of the species Amegilla (Zonamegilla) holmesi Rayment (Hymenoptera: Apidae) was evaluated in tomato plants, Lycopersicon esculentum Miller (Solanaceae), cultivated in two greenhouse chambers. Bluebanded bee pollination was compared with mechanical pollination and no supplementary pollination. Pollination effectiveness was compared between treatments by using the percentage of fruit set, fruit weight, fruit diameter, fruit roundness, and the number of seeds per fruit. Both the bluebanded bee pollination and the mechanical pollination treatments significantly increased fruit set, individual fruit weight, and diameter compared with the control treatment. Fruit were also significantly rounder and contained significantly more seeds. Positive correlations were found for fruit weight versus seed number, maximum diameter versus seed number and minimum diameter versus seed number. We conclude that the use of A. holmesi for pollinating greenhouse tomatoes in Australia may be an effective alternative to the use of mechanical pollination. [ABSTRACT FROM AUTHOR]

Disease Symptoms: Symptoms include water-soaked areas surrounded by chlorosis turning into necrotic spots on all aerial parts of plants. On tomato fruits, small, water-soaked, or slightly raised pale-green spots with greenish-white halos are formed, ultimately becoming dark brown and slightly sunken with a scabby or wart-like surface., Host Range: Main and economically important hosts include different types of tomatoes and peppers. Alternative solanaceous and nonsolanaceous hosts include Datura spp., Hyoscyamus spp., Lycium spp., Nicotiana rustica, Physalis spp., Solanum spp., Amaranthus lividus, Emilia fosbergii, Euphorbia heterophylla, Nicandra physaloides, Physalis pubescens, Sida glomerata, and Solanum americanum., Taxonomic Status of the Pathogen: Domain, Bacteria; phylum, Proteobacteria; class, Gammaproteobacteria; order, Xanthomonadales; family, Xanthomonadaceae; genus, Xanthomonas; species, X. euvesicatoria, X. hortorum, X. vesicatoria., Synonyms (nonpreferred Scientific Names): Bacterium exitiosum, Bacterium vesicatorium, Phytomonas exitiosa, Phytomonas vesicatoria, Pseudomonas exitiosa, Pseudomonas gardneri, Pseudomonas vesicatoria, Xanthomonas axonopodis pv. vesicatoria, Xanthomonas campestris pv. vesicatoria, Xanthomonas cynarae pv. gardneri, Xanthomonas gardneri, Xanthomonas perforans., Microbiological Properties: Colonies are gram-negative, oxidase-negative, and catalase-positive and have oxidative metabolism. Pale-yellow domed circular colonies of 1-2 mm in diameter grow on general culture media., Distribution: The bacteria are widespread in Africa, Brazil, Canada and the USA, Australia, eastern Europe, and south-east Asia. Occurrence in western Europe is restricted., Phytosanitary Categorization: A2 no. 157, EU Annex designation II/A2., Eppo Codes: XANTEU, XANTGA, XANTPF, XANTVE., (© 2021 The Authors. Molecular Plant Pathology published by British Society for Plant Pathology and John Wiley & Sons Ltd.)

Premise: Five to six percent of angiosperm species exhibit a dioecious sexual system, with unisexual "male" or "female" flowers borne on separate plants. The consequent need for inter-individual pollen exchange is a special challenge for taxa where pollen is the sole pollinator reward. Dioecious Australian Solanum assure visits from pollen-foraging bees via production of inaperturate pollen in functionally female (morphologically bisexual) flowers. Biochemical composition of pollen from Australian Solanum has not been assessed nor compared to porate pollen from staminate flowers to reveal whether these flowers differ in their pollinator reward potential., Methods: Porate pollen from male flowers and inaperturate pollen from functionally female flowers of two functionally dioecious Australian species were compared for protein and amino acid content. We also assessed pollen from bisexual and staminate flowers of a closely related andromonoecious species, in which all pollen is porate, as a comparison across co-occurring sexual systems., Results: In both functionally dioecious species, porate pollen grains from staminate flowers had significantly higher levels of proteins and amino acids than inaperturate pollen grains from functionally female flowers. Levels of proteins and amino acids were highest in bisexual and staminate flowers of the andromonoecious species., Conclusions: Higher levels of proteins and amino acids in porate pollen of "male" flowers in our functionally dioecious Solanum species suggests a greater nutritive reward for bees foraging on "male" plants than for those foraging on functionally "female" plants. Greater reward in porate pollen (including andromonoecious species) may be connected to the potential to generate a pollen tube., (© 2021 The Authors. American Journal of Botany published by Wiley Periodicals LLC on behalf of Botanical Society of America.)

• We attempted to circumscribe the fundamental host-range of Leptinotarsa texana. • The fundamental host-range is now expanded to include Potato and Archaesolanum. • We consider why earlier work did not include Potato in the fundamental host-range. • We argue there are important differences between modern potato cultivars. • We recommend thorough cultivar selection, justification and reporting. The leaf beetle Leptinotarsa texana Schaeffer (Coleoptera: Chrysomelidae) was introduced to South Africa from the USA to control silverleaf nightshade Solanum elaeagnifolium Cav. (Solanales: Solanaceae). Subsequent post-release studies in South Africa found the beetle to be an effective, host-specific biocontrol agent of S. elaeagnifolium. Leptinotarsa texana has potential for biological control of S. elaeagnifolium in other countries where the weed adversely impacts agricultural production, including Australia. However, L. texana can only be introduced to Australia if risk analysis demonstrates that the agent poses a negligible or very low risk to the environment and economy. We initiated an assessment of the agent's possible impact in Australia by prioritising non-target species, and conducting quarantine laboratory experiments on 49 Australian native species and economically important plant species and cultivars. We observed feeding damage greater than 50% leaf area removed on plants of 12 Australian Solanum spp. and two crop species (potato Solanum tuberosum L. and eggplant Solanum melongena L.). Leptinotarsa texana successfully developed from first instar larva to adult on 15 Australian Solanum spp. and two crop species (a single eggplant cultivar and four potato cultivars). When given a choice of S. elaeagnifolium and 10 Australian Solanum spp. in a large cage experiment, L. texana oviposited on S. elaeagnifolium and three of the non-target Australian Solanum spp. We consider possible reasons why potato was not found to be within the beetle's fundamental host-range in previous host-specificity experiments, and argue there are important differences between potato cultivars that have implications for future host-specificity testing. We outline priorities for further risk analysis, and criteria for assessing the feasibility of these approaches in different contexts. [ABSTRACT FROM AUTHOR]

Premise: Solanaceae is a scientifically and economically important angiosperm family with a minimal fossil record and an intriguing early evolutionary history. Here, we report a newly discovered fossil lantern fruit with a suite of features characteristic of Physalideae within Solanaceae. The fossil comes from the early Eocene Laguna del Hunco site (ca. 52 Ma) in Chubut, Argentina, which previously yielded the only other physaloid fruit fossil, Physalis infinemundi., Methods: The fruit morphology and calyx venation pattern of the new fossil were compared with P. infinemundi and extant species of Solanaceae., Results: Physalis hunickenii sp. nov. is clearly distinct from P. infinemundi in its fruiting calyx with wider primary veins, longer and thinner lobes, and especially in its venation pattern with high density, transverse tertiary veins; these features support its placement in a new species. In comparison with extant physaloid genera, the calyx venation pattern and other diagnostic traits reinforce placement of the new fossil, like P. infinemundi, within the tribe Physalideae of Solanaceae., Conclusions: Both species of fossil nightshades from Laguna del Hunco represent crown-group Solanaceae but are older than all prior age estimates of the family. Although at least 20 transoceanic dispersals have been proposed as the driver of range expansion of Solanaceae, the Patagonian fossils push back the diversification of the family to Gondwanan times. Thus, overland dispersal across Gondwana is now a likely scenario for at least some biogeographic patterns, in light of the ancient trans-Antarctic land connections between South America and Australia., (© 2020 Botanical Society of America.)