Plant-soil interactions during the native and exotic range expansion of an annual plant

We thank the greenhouse and technical staff at UC Santa Cruz and NIOO-KNAW for facilities and plant care, especially Jim Velzy and Sylvie Childress, and Renske Jongen and Freddy C. ten Hooven. We are grateful to Colby Cole, Asa Conover, Kelsey Songer, and Andrew Lopez for planting, harvesting, and root washing. Many thanks to Matthew Hartfield, Josie Borden, and Dante Park for their fieldwork assistance. We appreciate the permitting agencies that allowed us to collect seed and soil for this study: US Forest Service, Santa Clara County Parks, Midpeninsula Regional Open Space District, Don Edwards San Francisco Bay National Wildlife Refuge, and the Santa Clara Valley Water District. Seeds were collected following the Nagoya Protocol (French certificate of compliance TREL2302365S/653) and imported into the United States using APHIS permit P37-18-01389. This research was funded by the United States Department of Agriculture, National Institute of Food and Agriculture (Agriculture and Food Research Initiative Grant 2020-67013-31856 to I.M.P). N.L. acknowledges support from the Swiss National Science Foundation (Early.Postdoc mobility fellowship P2EZP3_178481), Natural Environment Research Council (Standard Grant NE/W006553/1), and the UKRI Horizon Europe Guarantee Research Scheme (Marie-Sklodowska-Curie European Fellowship EP/X023362/1). T.M.R.C. was funded by ENS de LyonPeer reviewe

Visuomotor processing is altered after peripheral nerve damage in neuralgic amyotrophy

Neuralgic amyotrophy is a common peripheral nerve disorder caused by autoimmune inflammation of the brachial plexus, clinically characterized by acute pain and weakness of the shoulder muscles, followed by motor impairment. Despite recovery of the peripheral nerves, patients often have residual motor dysfunction of the upper extremity, leading to persistent pain related to altered biomechanics of the shoulder region. Building on clinical signs that suggest a role for cerebral mechanisms in these residual complaints, here we show and characterize cerebral alterations following neuralgic amyotrophy. Neuralgic amyotrophy patients often develop alternative motor strategies, which suggests that (mal)adaptations may occur in somatomotor and/or visuomotor brain areas. Here, we tested where changes in cerebral sensorimotor representations occur in neuralgic amyotrophy, while controlling for altered motor execution due to peripheral neuropathy. We additionally explore the relation between potential cerebral alterations in neuralgic amyotrophy and clinical symptoms. During functional MRI scanning, 39 neuralgic amyotrophy patients with persistent, lateralized symptoms in the right upper extremity and 23 matched healthy participants solved a hand laterality judgement task that can activate sensorimotor representations of the upper extremity, across somatomotor and visuomotor brain areas. Behavioural and cerebral responses confirmed the involvement of embodied, sensorimotor processes across groups. Compared with healthy participants, neuralgic amyotrophy patients were slower in hand laterality judgement and had decreased cerebral activity specific to their affected limb in two higher-order visual brain regions: the right extrastriate cortex and the parieto-occipital sulcus. Exploratory analyses revealed that across patients, extrastriate activity specific to the affected limb decreased as persistent pain increased, and affected limb-related parieto-occipital activity decreased as imagery performance of the affected limb became slower. These findings suggest that maladaptive cerebral plasticity in visuomotor areas involved in sensorimotor integration plays a role in residual motor dysfunction and subsequent persistent pain in neuralgic amyotrophy. Rehabilitation interventions that apply visuomotor strategies to improve sensorimotor integration may help to treat neuralgic amyotrophy patients

Метод интегрирования дифференциальных уравнений динамики электрических машин с вращающимся ротором

Для исследования переходных процессов в электротехнических системах, содержащих статические электромагнитные устройства, включенные в сложные электрические схемы, разработан программный комплекс Colo, функционирующий на основе магнитоэлектрических схем замещения в матричной форме. Главная матрица комплекса Colo содержит коэффициенты при искомых токах или магнитных потоках. Моделирование динамических процессов в электрических машинах с вращающимся ротором связано с интегрированием дифференциальных уравнений, в которые входят произведения искомых величин, поэтому непосредственно эти уравнения не могут решаться в программном комплексе Colo

Plant-soil interactions during the native and exotic range expansion of an annual plant

Range expansions, whether they are biological invasions or climate change-mediated range shifts, may have profound ecological and evolutionary consequences for plant-soil interactions. Range-expanding plants encounter soil biota with which they have a limited coevolutionary history, especially when introduced to a new continent. Past studies have found mixed results on whether plants experience positive or negative soil feedback interactions in their novel range, and these effects often change over time. One important theoretical explanation is that plants locally adapt to the soil pathogens and mutualists in their novel range. We tested this hypothesis in Dittrichia graveolens, an annual plant that is both expanding its European native range, initially coinciding with climate warming, and rapidly invading in California after human introduction. In parallel greenhouse experiments on both continents, we used plant genotypes and soils from five locations at the core and edge of each range to compare plant growth in soil inhabited by D. graveolens and nearby control microsites as a measure of plant-soil feedback. Plant-soil interactions were highly idiosyncratic across each range. On average, plant-soil feedbacks were more positive in the native range than in the exotic range. In line with the strongly heterogeneous pattern of soil responses along our biogeographic gradients, we found no evidence for evolutionary differentiation between plant genotypes from the core to edge of either range. Our results suggest that the evolution of plant-soil interactions during range expansion may be more strongly driven by local evolutionary dynamics varying across the range than by large-scale biogeographic shifts

Rapid evolution of phenology during range expansion with recent climate change

Although climate warming is expected to make habitat beyond species’ current cold range edge suitable for future colonization, this new habitat may present an array of biotic or abiotic conditions not experienced within the current range. Species’ ability to shift their range with climate change may therefore depend on how populations evolve in response to such novel environmental conditions. However, due to the recent nature of thus far observed range expansions, the role of rapid adaptation during climate change migration is only beginning to be understood. Here, we evaluated evolution during the recent native range expansion of the annual plant Dittrichia graveolens, which is spreading northward in Europe from the Mediterranean region. We examined genetically based differentiation between core and edge populations in their phenology, a trait that is likely under selection with shorter growing seasons and greater seasonality at northern latitudes. In parallel common garden experiments at range edges in Switzerland and the Netherlands, we grew plants from Dutch, Swiss, and central and southern French populations. Population genetic analysis following RAD-sequencing of these populations supported the hypothesized central France origins of the Swiss and Dutch range edge populations. We found that in both common gardens, northern plants flowered up to 4 weeks earlier than southern plants. This differentiation in phenology extended from the core of the range to the Netherlands, a region only reached from central France over approximately the last 50 years. Fitness decreased as plants flowered later, supporting the hypothesized benefits of earlier flowering at the range edge. Our results suggest that native range expanding populations can rapidly adapt to novel environmental conditions in the expanded range, potentially promoting their ability to spread.<br/

Evolution during population spread affects plant performance in stressful environments

ISSN:0022-047