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BackgroundAimsMethodsResultsConclusionsThe general characteristics of urban floras are well studied, but less information is available on the behaviour of species at the street scale.To discuss the phenology and dynamics of the street flora.Vascular plants in flower were recorded at monthly intervals from January 2016 in eight connected streets in a primarily residential area of urban Cambridge, which is neither markedly deprived nor especially affluent.There is a regular seasonal cycle with fewest flowering species in February or March and most in June or July. Monthly totals in winter are correlated with the mean minimum temperature of the preceding month, and occasional severe summer droughts reduce the number of species flowering in August. In 2023 and 2024 the cessation of herbicide use by the city council, combined with wet summer weather, led to record numbers of flowering species. Species flowering in all years and recorded in all streets, the basic street flora, contrast with persistent colonies of rare species and a large number of casual occurrences.The street flora has a core of species which may change over the decades, joined by an ever-fluctuating cast of transient species. [ABSTRACT FROM AUTHOR]

BACKGROUND: 2,4‐Dichlorophenoxyacetic acid (2,4‐D) and other auxinic herbicides are important for weed control in cropping systems globally. Weeds with resistance to 2,4‐D and other auxinic herbicides have evolved, including several populations of Sonchus oleraceus from multiple sites in Australia. We report the underlying mechanism in these populations that gives rise to auxinic herbicide resistance. RESULTS: We studied a total of three susceptible and eight resistant Sonchus oleraceus populations. All resistant populations had a deletion of three amino acids flanking the degron sequence of an Aux/IAA gene, SoIAA20, which was not found in the three susceptible populations. The eight populations with the resistant allele were also resistant to dicamba, fluroxypyr and clopyralid. The resistant plants also had reduced movement of 2,4‐D out of the treated tissues compared to susceptible plants. CONCLUSION: The paired deletion flanking the degron region of SoIAA20 likely provides resistance to 2,4‐D by restricting the movement of 2,4‐D from the treated tissue to the rest of the plant. We hypothesise that this deletion keeps the 2,4‐D bound to the target site. © 2024 The Author(s). Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

SUMMARY: As a result of extensive selection, two polyploid grass weeds, Hordeum glaucum (northern barley grass; 2n = 4x = 28) and Bromus diandrus (ripgut brome; 2n = 8x = 56), have evolved resistance to glyphosate, in Australia. Previous research suggested amplification of 5‐enolpyruvylshikimate‐3‐Phosphate synthase (EPSPS) gene confers resistance in these two weed species. The objective of this research was to investigate the genomic organization of the EPSPS gene in these two species through molecular cytogenetic analyses of fluorescence in situ hybridization (FISH) to understand possible mechanism of amplification of this gene. EPSPS copy number of H. glaucum and B. diandrus plants was estimated via quantitative polymerase chain reaction. The susceptible plants of both species had one copy of EPSPS, whereas the resistant plants of H. glaucum and B. diandrus had 14–17 and 16–32 copies, respectively. FISH analysis of glyphosate‐susceptible (Hg‐RWS) H. glaucum, revealed four faint signals of the EPSPS gene in two pairs of homologous chromosomes, at the telomeric region. The glyphosate‐resistant H. glaucum (Hg‐YP1) also showed amplification of EPSPS gene at telomeric regions in two pairs of homologous chromosomes, but the signals were brighter and appeared as cluster of EPSPS genes. Similarly, the glyphosate‐susceptible B. diandrus (Bd‐S) plants showed faint signals of EPSPS gene on two homologous chromosomes, at the telomeric position. However, samples of two glyphosate‐resistant, B. diandrus, Bd‐SA988 and Bd‐Vic showed much brighter hybridization signals of EPSPS gene, located at the telomere on two homologous chromosomes, suggesting an increase in EPSPS gene copies at this position. Overall, unequal crossover during meiosis may have triggered the initial EPSPS gene duplication sparking the evolution of glyphosate resistance. [ABSTRACT FROM AUTHOR]

Background: Adrenal vein sampling (AVS), integral to identifying surgically remediable unilateral primary aldosteronism (PA), is technically challenging and subject to fluctuations in cortisol and aldosterone secretion. Intra‐procedural adrenocorticotropic hormone (ACTH), conventionally administered as a 250‐μg bolus and/or 50 μg per hour infusion, increases cortisol and aldosterone secretion and can improve AVS success, but may cause discordant lateralisation compared to unstimulated AVS. Aims: To assess if AVS performed with ultra‐low dose ACTH infusion causes discordant lateralisation. Methods: Here, we describe our preliminary experience using an ultra‐low dose ACTH infusion AVS protocol. We retrospectively reviewed the results of consecutive AVS procedures (n = 37) performed with and without ultra‐low dose ACTH (1‐μg bolus followed by 1.25 μg per hour infusion). Results: Bilateral AV cannulation was successful in 70% of procedures pre‐ACTH and 89% post‐ACTH (p < 0.01). Sixty‐nine percent of studies lateralised pre‐ACTH and 55% post‐ACTH, improving to 79% when both groups were combined. Lateralisation was discordant in 11 cases, including eight in which lateralisation was present only on basal sampling, and three in which lateralisation occurred only with ACTH stimulation. Discussion: Overall, the decrease in lateralisation rates with ACTH was higher than previously reported for some protocols utilising conventional doses of ACTH. Our results suggest that AVS performed with ultra‐low dose ACTH can cause discordant lateralisation similar to AVS performed with conventional doses of ACTH. Conclusion: Prospective studies directly comparing low and conventional dose ACTH AVS protocols and long‐term patient outcomes are needed to help define the optimal ACTH dose for accurate PA subtyping. [ABSTRACT FROM AUTHOR]