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Aboveground herbivores and soil biota profoundly affect plant invasions. However, how they interactively affect plant invasions through plant-soil feedbacks (PSFs) remains unclear. To explore how herbivory by the introduced beetle Agasicles hygrophila affects Alternanthera philoxeroides invasions in China, we integrated multiyear field surveys and a 2-yr PSF experiment, in which we examined how herbivory affects PSFs on the performance of native and invasive plants and the introduced beetles. Despite increased herbivory from A. hygrophila, A. philoxeroides dominance over co-occurring congeneric native Alternanthera sessilis remained constant from 2014 to 2019. While occurring at lower abundances, A. sessilis experienced similar herbivore damage, suggesting apparent competitive effects. Our experiments revealed that herbivory on A. philoxeroides altered soil microbial communities, prolonged its negative PSF on A. sessilis, and decreased A. hygrophila larvae performance on the next-generation invasive plants. Consequently, A. hygrophila larvae performed better on leaves of natives than those of invasives when grown in soils conditioned by invasive plants defoliated by the introduced beetles. Our findings suggest that aboveground herbivory might promote rather than suppress A. philoxeroides invasion by enhancing its soil-mediated self-reinforcement, providing a novel mechanistic understanding of plant invasions. These findings highlight the need to incorporate an aboveground-belowground perspective during the assessment of potential biocontrol agents.

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Climate and plant invasion can shape biotic communities at large spatial scales. Yet, how diverse groups of organisms associated with an invasive plant change simultaneously with latitude and the roles of climate and plant invasion remains unclear. We conducted a field survey of plants (native vs exotic), soil fungi (pathogenic, saprotrophic, arbuscular mycorrhiza fungi (AMF) and ectomycorrhizal (EcM) fungi) and arthropods (herbivores, predators and detritivores) associated with the invasive plant Alternanthera philoxeroides at 49 sites spanning 14 latitudinal degrees in China. Results showed that diversity and composition of these functional groups changed differently with latitude, partially due to their specific responses to climate, invasion of A. philoxeroides and other biotic environments. Moreover, A. philoxeroides invasion and/or composition of other plants, rather than climate, predicted the diversity and richness of major functional groups and partly explained variance in composition of putative fungal pathogens. Our results suggest that climate and plant invasion could affect the diversity and composition of diverse groups of organisms simultaneously and their relative importance might vary among functional groups. Thus, it is necessary to explore latitudinal patterns and underlying drivers of diverse groups of organisms simultaneously to improve our ability to predict and mitigate threats posed by plant invasion and climate change.

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As the number of non-native invasive species in the world is increasing, there is a pressing need to understand the effects of invasive species on recipient biotic communities to improve our ability to migrate or relieve their potential negative effects on biodiversity and ecosystem functions. Plant invasions have been shown to impose great threats to aboveground biotic communities; however, invasive impacts on soil biota remain ambiguous, partially because of the paucity of studies with a large number of species across biogeographic gradients. Here, we characterized rhizosphere fungal communities of 53 native and invasive plants spanning approximately 1800 km in China, as well as eight pairs of phylogenetically related native versus invasive plants in a greenhouse experiment. The results of both field survey and greenhouse experiment showed that rhizosphere fungal composition was primarily predicted by plant phylogeny (e.g. family and species), and plant geographic origin (native vs. invasive) and abiotic factors had much smaller effects. We detected no differences in the number and relative abundance of total and family/species-specific OTUs (i.e. overall, pathogens and mutualists) associated with these native and invasive plants on average, suggesting novel co-evolution between native soil fungi and these invasive plants. These results suggest that non-native plant invasions had only a weak impact on soil fungi, partially due to stronger controls of plant evolution on rhizosphere fungi and adaptation of native fungi to these invasive species. Interestingly, rhizosphere fungal composition was more variable between invasive plants than between native plants at middle latitudes, potentially creating spatial variations in plant-soil interactions and, in turn, invasion dynamics. These novel findings highlight the importance of integrating phylogenetic and biogeographical approaches to explore invasive effects on native biota.

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Mutomo hill plant sanctuary is a ten-hectare piece of land in Kenya listed as a botanical garden under the Botanical Gardens Conservation International, originally established in 1964 with the aim of conserving indigenous flora from destructive anthropogenic activities. This paper presents ethnobotanical documentation of medicinal plants of Mutomo hill plant sanctuary and its environs. An ethnobotanical survey was carried out in Mutomo hill plant sanctuary and its environs with 48 herbalists aged between 32 and 96 years from July 2018 to February 2019 using a semistructured open-ended questionnaire. The plants were collected through random surveys with each herbalist in different ecotypes around the villages and within the Mutomo hill plant sanctuary. The Relative Frequency of Citation (RFC) for each species reported was calculated to determine the plant species frequently collected. In total, 68 different plant species distributed in 28 families and 54 genera were reported. The frequently used plant families were Leguminosae (13 species), Lamiaceae (6 species), and Euphorbiaceae (6 species). Shrubs (37%) and trees (34%) were the dominant growth habits reported. The most cited plant species were Cassia abbreviata Oliv. (RFC = 0.63), Acacia nilotica (L.). Delile (RFC = 0.54), Strychnos heningsii Gilg (RFC = 0.46), and Aloe secundiflora Engl. (RFC = 0.31). Root (19 species) and bark (19 species) were the frequently collected plant parts. Infectious diseases (33) and digestive system disorders (24) were reported to be managed with the majority of the plant species. This study contributes to safeguarding the traditional knowledge on medicinal plants in the study area, which is useful in appreciating and acknowledging the cultural heritage of the Kamba people from the local perspective of Mutomo area in Kenya. It also adds to the knowledge base and documentation of medicinal plants, which is useful information as potential data for drug development.

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BACKGROUND: The Wuliang Mountains of the Jingdong region is a settlement area of the Yi community located in south-western Yunnan Province in China. Due to its unique geographical location, this area harbours abundant medicinal plant resources. The medicinal plants used by the local people have a long history and play an important role in their daily life. During the long-term mixed lifestyle, the knowledge of traditional medicinal plants in different communities has been assimilated to some extent. Therefore, this paper is based on ethnobotanical investigations to document traditional medicinal plants used by local people and discuss the differences between the Yi and Han communities in the study area. METHODS: Data on traditional medicinal plants were collected from September 2016 to August 2017 in the Yi autonomous county of Jingdong. Seven townships and 16 villages were selected for the field investigations. Information was obtained through key informant interviews. A total of 44 key informants were interviewed, and all of them were herbalists or herbal sellers. RESULTS: In this study, a total of 302 traditional medicinal plant species belonging to 117 families and 252 genera were investigated and documented, most of which were obtained from herbalists. Although family Asteraceae was the most prevalent, with 27 species, the most commonly utilized species were members of family Papaveraceae, Dactylicapnos scandens (D. Don) Hutch., which is used as an antipyretic drug. Herbs comprised half of the total number of species, and the whole plant is the most frequently utilized plant part. The plants were used to treat more than 93 human diseases, with antipyretic drugs being the most common form of herbal medicine. The traditional medicinal plants used in the study area possess a high ratio of being documented in the literature. According to the analysis, the Chinese Pharmacopoeia recorded 76 species and the Resources of Traditional Chinese Medicine recorded 233 species of traditional medicinal plants. By evaluating the endangered status of the traditional medicinal plants in the study area, we found good conservation status of the cited medicinal plants. Regarding the similarity between the communities, there were significant differences between the Yi and Han communities, as indicated by the Jaccard similarity index (0.232). CONCLUSIONS: Medicinal plants are the embodiment of wisdom from our ancestors and play a significant role in treating various human disorders. As one of the birthplaces of Yi medicine, the study area possesses a high species diversity of traditional medicinal plants used by local people. With the rapid development of modern medicine, however, the inheritance of this valuable culture is facing enormous threats even though its potential value has not yet been fully explored. Therefore, some effective protection measures should be taken, and some modern techniques should be implemented to prove the safety and improve the scientific acceptance of the traditional medicinal plants.

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