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Plants produce diverse metabolites to cope with the challenges presented by complex and ever-changing environments. These challenges drive the diversification of specialized metabolites within and between plant species. However, we are just beginning to understand how frequently new alleles arise controlling specialized metabolite diversity and how the geographic distribution of these alleles may be structured by ecological and demographic pressures. Here, we measure the variation in specialized metabolites across a population of 797 natural Arabidopsis thaliana accessions. We show that a combination of geography, environmental parameters, demography and different genetic processes all combine to influence the specific chemotypes and their distribution. This showed that causal loci in specialized metabolism contain frequent independently generated alleles with patterns suggesting potential within-species convergence. This provides a new perspective about the complexity of the selective forces and mechanisms that shape the generation and distribution of allelic variation that may influence local adaptation.

The total solar eclipse of 21 August 2017 traversed ~5000 km from coast to coast of North America. In its 90-min span, sunlight dropped by three orders of magnitude and temperature by 10–15°C. To investigate impacts of these changes on bee (Hymenoptera: Apoidea) pollinators, we monitored their flights acoustically in natural habitats of Pacific Coast, Rocky Mountain, and Midwest regions. Temperature changes during the eclipse had little impact on bee activity. Most of the explained variation (R 2) in buzzing rate was attributable to changes in light intensity. Bees ceased flying during complete darkness at totality, but flight activity was unaffected by dim light in partial phases before and after totality. Flights of bees during partial phases of the eclipse lasted longer than flights made under full sun, showing that behavioral plasticity matched bee flight properties to changes in light intensity during the eclipse. Efforts of citizen scientists, including hundreds of school children, contributed to the scope and educational impact of this study. [ABSTRACT FROM AUTHOR]

Fusarium head blight (FHB), predominantly caused by Fusarium graminearum is one of the most economically important fungal diseases of small-grain cereals. Since the early 1990s, FHB has been a devastating wheat disease in parts of Canada and the United States, causing significant economic impacts on the cereal grain industry through reduced seed quality and yield, and grain contamination with fungal toxins (Brar et al. 2019). Spikes of wheat and barley with bleached spikelets and pinkish coloration were observed with low incidence and high severity in August 2021 field stripe rust nursery at UBC Totem Plant Science Farm in Vancouver, Canada (Supplementary File 1). FHB-like Symptomatic spikes were collected during the growing season. The Fusarium damaged kernels (FDK) were surface-sterilized with 1% sodium hypochlorite (NaOCl) for 1.5 min, rinsed three times in distilled water and dried using sterile filter paper discs in Biological Safety Cabinet. The kernels were placed on Petri dishes containing three layers of moist blotter papers and incubated in the dark at 22-25°C for 24 hours. The Petri dishes were transferred into a -20°C freezer for 24 hours, followed by five days of incubation at 22-25°C under fluorescent light, during which distilled water was added onto blotter papers every day to maintain moisture. After incubation, mycelium growing on kernels was transferred to potato dextrose agar (PDA) media and subcultured based on the colony and conidial morphology of F. graminearum (Leslie and Summerell 2006). The colonies selected grew white mycelia with a pink pigment at the bottom. Macroconidia with five to six septate were produced after seven days and microconidia were absent. Seven isolates derived from different wheat samples were derived from single conidia and identified based on amplicon sequencing using a MinION Flongle flow cell described by Boutigny et al. (2019). Reads which passed the integrated MinKNOW quality control step were mapped to the Partial translation elongation factor 1- α (EF1a) gene, using primers EF1-F2 (5'TCATC GGCCACGTCGACTCT3') and EF1-R3 (5'TACCAGCCTCGAACTCACCA3'). The consensus sequence for each sample was aligned to the reference sequence (JF740867.1) using BLASTn, revealing all the similarities of more than 99.5% (Supplementary File 2). The morphological characteristics (colony, pink pigment, shape of macroconidia, absence of microconidia) (Leslie and Summerell, 2006) and sequencing results indicated that the seven isolates from wheat were F. graminearum of the 3ADON chemotype. Besides, Koch's postulates were performed by spray-inoculating healthy inflorescences of eight wheat plants derived from the cross Avocet/CDC Silex at half anthesis stage (one isolate per plant and one non-inoculated control). Each spike was thoroughly sprayed with 1ml of spore suspension containing 5 × 104 conidia per ml (4-5 spikes per plant). The spikes on one plant were treated with distilled water (1 ml per spike) as a blank control. The inoculated spikes were covered with moist plastic bags for 48 hours, and the plants were placed in a growth chamber under a 12-h photoperiod at 18°C. Seven days later, spikes of the spores-treated plants exhibited bleached spikelets, which is a typical symptom of FHB, and there was no disease on the control plant. F. graminearum was re-isolated from FDK of diseased spikes using the isolation methodology and identified by morphology described above. To our knowledge and based on a literature review, this is the first report of F. graminearum causing FHB on wheat and barley in the Lower Mainland of British Columbia. The reason for the concealment of F. graminearum in BC might be the small acreage of commercially grown small-grain cereals. Further, there is limited cultivation of winter wheat and barley in the region for forage/silage, but the crops are harvested at the soft dough stage leaving limited grain/spike residue for the next crop. While presently there is very low acreage of cereal host crops of F. gramineraum in Lower Mainland, this acreage might increase in future years as winter cereals are slowly expanding in the region as cover crops, forages, and even grain production for sale to forgae producers or for local breweries in case of barley; therefore, finding of F. gramineraum could have economic consequences on cereal production in the region in future. Further investigation is needed to better understand the aggressiveness of the strains and their population structure of the pathogen in the Region.

Background: The 13-item Symptom Distress Scale (SDS) is a widely used symptom measurement tool, yet a systematic review summarizing the symptom knowledge generated from its use in patients with advanced cancer is nonexistent., Objectives: This was a systematic review of the research literature in which investigators utilized the SDS as the measure of symptoms in patients with advanced cancer., Methods: We searched PubMed, CINAHL, EMBASE, and Web of Science for primary research studies published between 1978 and 2013 that utilized the SDS as the measurement tool in patients with advanced cancer. Nine hundred eighteen documents were found. Applying inclusion/exclusion criteria, 21 articles and 2 dissertations were included., Results: The majority of investigators utilized descriptive, cross-sectional research designs conducted with convenience samples. Inconsistent reporting of SDS total scores, individual item scores, age ranges and means, gender distributions, cancer types, cancer stages, and psychometric properties made comparisons difficult. Available mean SDS scores ranged from 17.6 to 38.8. Reports of internal consistency ranged from 0.67 to 0.88. Weighted means indicated fatigue to be the most prevalent and distressing symptom. Appetite ranked higher than pain intensity and pain frequency., Conclusions: The SDS captures the patient's symptom experience in a manner that informs the researcher or clinician about the severity of the respondents' reported symptom distress., Implications for Practice: The SDS is widely used in a variety of cancer diagnoses. The SDS is a tool clinicians can use to assess 11 symptoms experienced by patients with advanced cancer.