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We assessed the impact of road disturbances on the dominant mycorrhizal types in ecosystems at the global level and how this mechanism can potentially lead to lasting plant community changes. We used a database of coordinated plant community surveys following mountain roads from 894 plots in 11 mountain regions across the globe in combination with an existing database of mycorrhizal–plant associations in order to approximate the relative abundance of mycorrhizal types in natural and disturbed environments. Our findings show that roadside disturbance promotes the cover of plants associated with arbuscular mycorrhizal (AM) fungi. This effect is especially strong in colder mountain environments and in mountain regions where plant communities are dominated by ectomycorrhizal (EcM) or ericoid‐mycorrhizal (ErM) associations. Furthermore, non‐native plant species, which we confirmed to be mostly AM plants, are more successful in environments dominated by AM associations. These biogeographical patterns suggest that changes in mycorrhizal types could be a crucial factor in the worldwide impact of anthropogenic disturbances on mountain ecosystems. Indeed, roadsides foster AM‐dominated systems, where AM‐fungi might aid AM‐associated plant species while potentially reducing the biotic resistance against invasive non‐native species, often also associated with AM networks. Restoration efforts in mountain ecosystems will have to contend with changes in the fundamental make‐up of EcM‐ and ErM plant communities induced by roadside disturbance. [ABSTRACT FROM AUTHOR]

Huge economic costs and ecological impacts of invasive alien species (IAS) in the protected areas (PAs) worldwide make their timely prediction and potential risk assessment of central importance for effective management. While the preborder weed risk assessment framework has been extensively evaluated and implemented, the postborder species risk assessment framework has not been subjected to the same degree of scrutiny. Here we used a rather more realistic modified version of the Australian Weed Risk framework (AWRM) for Dachigam National Park (DNP) in Kashmir Himalaya against 84 plant species, including 55 alien species and 29 fast spreading native species, for risk analysis. We found two very high‐risk species, three high‐risk species, 10 medium‐risk species, 29 low‐risk species, and 40 negligible‐risk species in the DNP. The containment scores accordingly ranged from 14.4 to 293.5 comprising of 27 species that can be contained with very high feasibility, 23 species with high feasibility, 14 species with medium feasibility, and 12 species which cannot be contained easily thereby having low feasibility of containment (FOC) score. However, eight species which have a negligible FOC score are difficult to contain within their infestation sites. Our results demonstrate the merit of the AWRM with a caution that the necessary region‐specific modifications may help in its better implementation. Overall, these results provide quite a promising tool in the hands of protected area managers to timely and effectively deal with the problem of plant invasions. [ABSTRACT FROM AUTHOR]

In view of the mutualistic facilitation of invasive plants, we examined the mycorrhizal status of 469 species, including 335 alien and 134 native to the region of Kashmir Himalaya, India. Data on the mycorrhizal status and altitudinal range of the target species were obtained using some peer reviewed primary published and web based sources. One sample Z score test and regression analysis were performed to workout the relative proportion of mycorrhizal and non-mycorrhizal plants in different altitudinal belts and relationship of mycorrhizal symbiosis with increasing altitude, respectively. With increasing altitude, the mycorrhizal association of both the alien and native plant species showed a decreasing trend, although alien plant species showed much stronger negative values than native species do. Both aliens and native species showed significantly higher proportion of mycorrhizal species compared to non-mycorrhizal counterparts in all the vegetation zones (Temperate, Montane, Sub-alpine and Alpine). Interestingly, in none of the vegetation zones do aliens and natives differ in terms of their mycorrhizal and non-mycorrhizal species fractions, suggesting that change in mycorrhizal symbioses along any elevational gradient occurs more due to restrictions on mycorrhizal fungi survival than due to the identity of the species concerned. These trends call for further studies at wider geographical scales to better understand the mechanisms and implications of mycorrhizal associations for managementof alien plant invasion in such eco-climatically sensitive regions, especially in the context of climate change. [ABSTRACT FROM AUTHOR]

Presently alien species are invading least invaded areas largely because of anthropogenic activities. The distribution of alien plant species is determined by many factors and in mountainous areas altitude is one of the most important factors determining the distribution of plant species. In order to understand the role of roads in distribution of alien plant species along elevational gradient, two road transects were selected. These two road transects were divided into equally spaced altitudinal zones and at each site 3 plots were selected. A total of 200 species were recorded out of which 133 were native and 67 were alien. Total species richness decreased with altitude while as native species richness increased. Level of invasion expressed as proportion of alien plant species decreased with altitude in all the three plots. In addition, floristic similarity between plots decreased with increasing altitudinal difference. From the present study it is clear that alien plant species have not invaded the alpine areas to a large extent but anthropogenic activities like unplanned road development and promotion of tourism in the area is likely to threaten the uninvaded high altitude areas of the region. [ABSTRACT FROM AUTHOR]

Background: Invasive species can be a major threat to native biodiversity and the number of invasive plant species is increasing across the globe. Population genetic studies of invasive species can provide key insights into their invasion history and ensuing evolution, but also for their control. Here we genetically characterise populations of Impatiens glandulifera, an invasive plant in Europe that can have a major impact on native plant communities. We compared populations from the species' native range in Kashmir, India, to those in its invaded range, along a latitudinal gradient in Europe. For comparison, the results from 39 other studies of genetic diversity in invasive species were collated. Results: Our results suggest that I. glandulifera was established in the wild in Europe at least twice, from an area outside of our Kashmir study area. Our results further revealed that the genetic diversity in invasive populations of I. glandulifera is unusually low compared to native populations, in particular when compared to other invasive species. Genetic drift rather than mutation seems to have played a role in differentiating populations in Europe. We find evidence of limitations to local gene flow after introduction to Europe, but somewhat less restrictions in the native range. I. glandulifera populations with significant inbreeding were only found in the species' native range and invasive species in general showed no increase in inbreeding upon leaving their native ranges. In Europe we detect cases of migration between distantly located populations. Human activities therefore seem to, at least partially, have facilitated not only introductions, but also further spread of I. glandulifera across Europe. Conclusions: Although multiple introductions will facilitate the retention of genetic diversity in invasive ranges, widespread invasive species can remain genetically relatively invariant also after multiple introductions. Phenotypic plasticity may therefore be an important component of the successful spread of Impatiens glandulifera across Europe. [ABSTRACT FROM AUTHOR]

Copyright of Tropical Ecology is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Aims In view of the growing interest in modelling the potential spread of invasive species, prediction of plant invasiveness on the basis of native range size holds considerable promise. Our objective was to use a simple model to evaluate whether a wider native range predisposes plant species to become invasive in non-native regions and to easily identify potential invaders on this basis. The Kashmir Himalayan alien flora, of which a large proportion is native to Europe, was used to test this model. Methods The Kashmir Himalayan alien flora comprises 436 species of vascular plants at different stages of invasion. We focussed on plant species at two critical invasion stages (sensu Colautti and MacIsaac 2004), i.e. Stage II (species that are just at the earliest phase of introduction) and Stage V (species that are widespread and dominant in the invaded region and are thus considered invasive). We used the territorial distribution in Europe (number of countries) as a surrogate for the native range size of plants of European origin. Important Findings Using a subset of 88 species, for which information on the native European range was available, we showed that a large proportion (68%) of Stage II species growing in the Kashmir Valley had a relatively restricted European range (present in ≤20 countries); on the other hand, 77% of Stage V species had an extensive native range (present in >20 countries). We consequently hypothesized that 14 Kashmir Himalayan Stage II species of European origin that are distributed in >20 European countries are at risk of becoming future invaders in Kashmir. On the other hand, those Kashmir Himalayan Stage II species of European origin distributed in ≤20 European countries are less likely to become invasive. Although this analysis is quite simple, the data suggest that a wider native range is a good predictor of plant invasiveness and could be used as a simple and low-cost early warning tool in predicting potential invasive species. [ABSTRACT FROM PUBLISHER]

Copyright of Tropical Ecology is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A continuing lack of consensus on the operational characterisation of alien invasive species (AIS) in invasion biology has hampered the integration of research results generated worldwide. This impedes our progress in devising sound management strategies to stem the tide of biological invasions. In this regard, we here use the neutral terminology model of Colautti and MacIsaac (Divers Distrib 10:135--141, 2004) (CM model) for the characterization of alien invasive flora of the Kashmir Himalaya, India; and more emphatically, expound the utility of such a stage-based operational framework in the management of plant invasions. Out of the total of 436 alien invasive plant species recorded in the region, the number of species belonging to invasion stages II, III, IVa, IVb and V was 119, 107, 56, 77 and 77 species, respectively. In terms of relative proportion of species belonging to the different invasion stages, trees dominated the Stage-V (31.25%), followed by aquatics, subshrubs, biennial herbs, perennial herbs, annual herbs and shrubs, in descending order. Based on the results obtained in the present investigation, and in an attempt to link the characterisation of AIS with the management of plant invasions, we here propose a hierarchical management framework based on prediction, prevention, prescription, and public awareness. While the present study focuses on plants only, the proposed management framework can be operationally used across different taxonomic groups, and within varied ecosystems, with potentially immense management implications. [ABSTRACT FROM AUTHOR]

Recent studies have established the controlling influence of rhizospheric biota, especially arbuscular mycorrhizal fungi (AMF), on colonization and spread of some alien plants in their introduced range. But how AMF from different geographical sources influence traits that contribute to invasiveness, particularly in presence of neighbouring plants of other species, has been rarely investigated. Thus, we compared the influence of some local (Kashmir Himalayan isolates) and non-local (isolates from Rajasthan, India) AMF isolates of Glomus moseae, G. fasciculatum and Gigaspora margarita on vegetative and reproductive attributes of Mayweed Chamomile ( Anthemis cotula L.), a highly invasive species in the Kashmir Himalaya, India. We also examined whether or not the neighbouring plant species, namely Daucus carota L. (Apiaceae) alters the mutualistic interaction between the AMF and A. cotula. Pot experiments revealed greater positive impact of the local than the non-local AMF on vegetative as well as reproductive attributes of A. cotula. Experimental field studies showed that the incidence of highly prevalent Arum-type mycorrhizal colonization in natural populations of A. cotula was reduced in presence of D. carota. Besides, the local AMF significantly promoted growth of A. cotula more than D. carota under mixed-culture conditions. These results suggest that the facilitation of some alien plant invasions by AMF needs to be considered together with plant–plant interactions and invasion-induced changes in the soil microbial community. [ABSTRACT FROM AUTHOR]

Abstract: Whilst the importance of arbuscular mycorrhizal fungi (AMF) in invasive spread of some alien plant species has been recently established, it is unclear how such plants respond to AMF from different geographical sources. Besides, influence of different co-occurring plant species on the AMF-mediated invasiveness of alien species, though rarely investigated, is pivotal to the explicit understanding of the feedback between arbuscular mycorrhizal fungi and alien plant invasions. We therefore examined the influence of local (Kashmir Himalyan isolates) and foreign (isolates from Rajasthan, India) AMF on invasiveness of alien Anthemis cotula vis-à-vis the effect of three common co-occurring neighbours, Conyza canadensis, Galinsoga parviflora and Sisymbrium loeselii. Field studies revealed high incidence of Arum-type mycorrhizal colonization in natural populations of A. cotula and the pot trials confirmed the reliance of its invasiveness on AMF with the more favourable effect of local than foreign AMF. The mycorrhizal colonization intensity in field populations of A. cotula was strongly influenced by neighbour identity with major reduction recorded in the presence of S. loeselii (a cruciferous non-host) in comparison to other con-familial neighbours. Pot experiments confirmed the differential effect of co-occurring species on A. cotula''s invasive traits. These results signify that the facilitative role of AMF communities in invasion by some alien plants is contingent upon neighbour identity and the present approach provides not only a framework for further examination of the invasive plant–soil biota feedback, but also many important management implications. [Copyright &y& Elsevier]

In recent years, the microbiome has attracted much attention because of the multiple roles and functions that microbes play in plants, animals, and human beings. Seed-associated microbes are of particular interest in being the initial microbial inoculum that affects the critical early life stages of a plant. The seed-microbe interactions are also known to improve nutrient acquisition, resilience against pathogens, and resistance against abiotic stresses. Despite these diverse roles, the seed microbiome has received little attention in plant ecology. Thus, we review the current knowledge on seed microbial diversity, community structure, and functions obtained through culture-dependent and culture-independent approaches. Furthermore, we present a comprehensive synthesis of the ecological literature on seed-microbe interactions to better understand the impact of these interactions on plant health and productivity. We suggest that future research should focus on the role of the seed microbiome in the establishment, colonization and spread of plant species in their native and non-native ranges as it may provide new insights into conservation biology and invasion ecology. • Seed microbiome represents a reservoir of microbial taxa, that has co-evolved with the host plant species and provide special growth traits for plant survival. • Seed-associated-microbes are transmitted vertically or horizontally via three pathways: (i) Internal pathway, (ii) floral pathway (iii) external pathway. • Seed microbiome acts as initial inoculum for the host, influencing the critical early life stages of a plant such as seed dormancy and germination. • Under climate change, the seed microbiome may improve plant's adaptation by impacting host metabolism, behaviour and physiology. • Seed microbiome by mediating dormancy, germination, growth, stress tolerance may also benefit invasive plants in establishment and spread. [ABSTRACT FROM AUTHOR]

The article discusses the plant invasion of Leucanthemum vulgare Lam. in Kashmir Valley, India. It accounts the detrimental presence of L. vulgare plant, also known as ox-eye daisy in the valley, intentionally introduced in the area as an ornamental plant. It also explores the effects of the L. vulgare invasion into the other plant species, further regarding on ways to control the invasive alien species.

Abstract: Background: Many studies have shown that alien species richness pattern follows that of native species richness patterns along environmental gradients, without taking the specific composition of the two groups into account. Objectives: To compare species richness patterns of native and alien woody plants along an altitudinal gradient in Kashmir Himalaya, India, and to analyse the specific composition, e.g. proportion of life forms. Methods: Analysis of secondary data from published floristic inventories. The gradient (500–4800m asl) was split into 100m bands and presence/absence data for each species were obtained, for each band. Results: Species richness of both native and alien species followed a hump-shaped distribution. Alien species richness dropped faster above 2000masl than the native did. The ratio of trees to shrubs decreased monotonically along the gradient in native species, but showed a peak at c. 2500masl in alien species. Alien species flowered in average earlier than native species. Conclusions: The change of species richness of native and alien species along altitude is similar, but the proportion of life forms is not. Most likely both climatic and socio-economic factors affect alien species richness and its specific composition in the Kashmir Himalaya. [Copyright &y& Elsevier]