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Phyllosphere or aerial surface of plants represents the globally largest and peculiar microbial habitat that inhabits diverse and rich communities of bacteria, fungi, viruses, cyanobacteria, actinobacteria, nematodes, and protozoans. These hyperdiverse microbial communities are related to the host's specific functional traits and influence the host's physiology and the ecosystem's functioning. In the last few years, significant advances have been made in unravelling several aspects of phyllosphere microbiology, including diversity and microbial community composition, dynamics, and functional interactions. This review highlights the current knowledge about the assembly, structure, and composition of phyllosphere microbial communities across spatio-temporal scales, besides functional significance of different microbial communities to the plant host and the surrounding environment. The knowledge will help develop strategies for modelling and manipulating these highly beneficial microbial consortia for furthering scientific inquiry into their interactions with the host plants and also for their useful and economic utilization., (Copyright © 2021 Elsevier GmbH. All rights reserved.)

Understanding the species richness and β-diversity patterns along elevation gradients can aid in formulating effective conservation strategies particularly in areas where local anthropogenic stresses and climate change are quite significant as in the Himalaya. Thus, we studied macrolichen richness and β-diversity along elevational gradients at three sites, namely Kashmir (2200 to 3800 m a.m.s.l), Uttarakhand (2000-3700 m a.m.s.l) and Sikkim (1700 to 4000 m a.m.s.l) which cover much of the Indian Himalayan Arc. In all, 245 macrolichen species belonging to 77 genera and 26 families were collected from the three sites. Only 11 species, 20 genera and 11 families were common among the three transects. Despite the differences in species composition, the dominant functional groups in the three sites were the same: foliose, fruticose and corticolous forms. The hump-shaped elevation pattern in species richness was exhibited by most of the lichen groups, though an inverse hump-shaped pattern was also observed in certain cases. β-diversity (β sor ) based on all pairs of comparisons along an elevation gradient varied from 0.48 to 0.58 in Kashmir, 0.03 to 0.63 in Uttarakhand and 0.46 to 0.77 in Sikkim. The contribution of turnover to β-diversity was more than nestedness at all the three transects. Along elevation β-diversity and its components of turnover and nestedness varied significantly with elevation. While species turnover increased significantly along the elevation in all the three transects, nestedness decreased significantly in Kashmir and Sikkim transects but increased significantly in the Uttarakhand transect. Except for the Kashmir Himalayan elevation transect, stepwise β-diversity and its components of turnover and nestedness did not vary significantly with elevation. The present study, the first of its kind in the Himalayan region, clearly brings out that macrolichen species richness, β-diversity, and its components of turnover and nestedness vary along the elevation gradients across the Himalayan Arc. It also highlights that contribution of turnover to β-diversity is higher in comparison to nestedness at all the three transects. The variations in species richness and diversity along elevation gradients underpin the importance of considering elevational gradients in planning conservation strategies., (© 2021. The Author(s).)

The impact of invasive species across their native and nonnative ranges is poorly quantified and this impedes a complete understanding of biological invasions. We compared the impact of the native North American plant, Conyza canadensis, which is invasive to Eurasia, on species richness at home and in a number of introduced regions through well replicated transcontinental field studies, glasshouse experiments and individual-based models. Our results demonstrated mostly negative relationships between C. canadensis abundance and native species richness in nonnative ranges, but either positive or no relationships in its native North American range. In glasshouse experiments, the total biomass of Conyza was suppressed more by species from its native range than by species from regions where it is nonnative, but the effects of Conyza on other species did not show a consistent biogeographical pattern. Finally, individual-based models led to the exclusion of Conyza from North American scenarios but to high abundances in scenarios with species from the nonnative ranges of Conyza. We illustrate biogeographical differences in the impact of an invader across regional scales and suggest that inherent differences in one specific aspect of competitive ability, tolerance to the effects of other species, may play some role in these differences., (© 2014 The Authors. New Phytologist © 2014 New Phytologist Trust.)

The present study was undertaken to document the ectomycorrhizal diversity associated with the Cedrus deodara and Pinus wallichiana in the Kashmir Himalaya, India. The extensive field surveys carried out in the Kashmir Himalaya at five study sites resulted in the collection and identification of 76 potential ectomycorrhizal fungal species associated with the Cedrus deodara and Pinus wallichiana. Maximum 32 number of species were found associated with Pinus wallichiana, 19 with Cedrus deodara and 25 species were found growing in association with both the conifers. The present study reveals that Cedrus deodara and Pinus wallichiana in the Kashmir Himalaya, India harbour diverse ectomycorrhizal fungal species.

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 © 2011. Published by Elsevier Inc.)

Systematic conservation planning aims to identify the species that are in need of immediate conservation and minimise biodiversity loss. Importantly, conservation planners seek to determine where to allocate limited resources first. The International Union for the Conservation of Nature (IUCN) Red List of Threatened Species incorporates data not only on threats to species, but also on species distributions and ecological requirements. These datasets have proven useful for determining the most prioritised species for conservation, from the global level down to the scale of region. Assigning a particular threat category to the species in accordance with IUCN regional guidelines not only helps in identifying the key elements which are in immediate need of conservation but also help in setting the priorities for their sustainable management. During the present study, threat status of six endemic medicinal plant species were evaluated as per IUCN Red List Categories and Criteria 2010 version 8.1 following Guidelines for Application of IUCN Red List Criteria at Regional Levels 2003 version 3.0. The evaluated species are subjected to eight different types of threats in the studied area; which have rendered these species threatened. Three of these ( Atropa acuminata , Aquilegia nivalis and Corydalis cashmeriana ) meet the criteria for Endangered ( EN ) threat category while the remaining three species ( Fritillaria roylei , Rheum webbianum and Lagotis cashmeriana ) qualify for the Vulnerable ( VU ) threat category. These six species are thus threatened in nature and needs immediate conservation strategies for sustainable use. The study acts as a test case for the successful conservation of large number of important medicinal plant species of Kashmir Himalaya – a hot spot of biodiversity. [ABSTRACT FROM AUTHOR]

Observational and manipulative studies have revealed that alien plant invasions are an outcome of interplay between a myriad of biotic and abiotic factors operating at various spatio-temporal stages and scales. Despite the salient role of ubiquitous arbuscular mycorrhizal (AM) fungi in plant interactions, studies exploring the role of such symbionts in invasiveness of alien species and invasibility of communities are limited, in part because of difficult-culturablilty of AM fungi on artificial media and apparent complexities in manipulations of AM-plant interactions in field and laboratory experiments. Moreover, analysis of the AM-plant invasion studies conducted so far have yielded contradictory results with some indicating facilitation of invasion by AM fungi and others its inhibition. Other studies have indicated that arbuscular mycorrhizal symbiosis has no effect on invasiveness of alien plants. While arbuscular mycorrhizas may facilitate invasiveness of some alien plants, such plants may also potentially impact mycorrhizal community structure and functions in the invaded habitats in different ways. The present review addresses these paradoxically conflicting observations in the context of mutualism-commensalism-parasitism gradient that characterizes the relationship between AM fungi and their alien vs. native hosts and also discusses the influence of alien invasive plants on mycorrhizal community structure of invaded ecosystems. Through critical analysis of costs and benefits for invasive plants that associate with AM fungi in their introduced range, invasion-induced shifts in AM mutualism are evaluated in the context of their impact on native biodiversity. Underlining limitations of methodologies and experimental designs usually employed to understand AM-mediated plant invasiveness, we proposes herein some alternative frameworks and experimental approaches to overcome these limitations. [ABSTRACT FROM AUTHOR]

In view of being an important process in ecosystems and of great significance to ecological studies, net primary productivity, together with accumulation of plant dry matter and its transfer dynamics, was studied in two grasslands occurring at elevations of 1600 m (low elevation grassland) and 1950 m above mean sea level (high elevation grassland). Thirty eight species occurred at the low elevation grassland and 11 species were recorded at the high elevation grassland. Maximum aboveground live plant biomass in low elevation grassland was 422.00 g m-2 and the same in high elevation grassland was 2189.30 g m-2. Peak values of standing dead material in the two grasslands were 558.6 g m-2 and 2377.2 g m-2, respectively. The litter mass in the low elevation grassland ranged from a low of 156 g m-2 to a high of 1111 g m-2 while as the corresponding Values in the high elvation grassland were 840 g m-2 and 1590 g m-2, respectively. Belowground drymass was also higher (5016.50 g m-2 ) in high elevation grassland compared to low elevation grassland wherein peak belowground drymass was 1691.50 g m-2. Aboveground Net Productivity (ANP), Belowground Net productivity (BNP) and Total Net Productivity (TNP) values in the low elevation grassland were 1467.76 g m-2y-1, 1940.00 g m-2y-1, and 3408.21 g m-2y-1, respectively. The corresponding values in the high elevation grassland were 3088.69, 6072.50 and 9161.19 g m-2y-1. Of the total TNP, 43% and 34% were transferred to ANP in low- and high elevation grasslands, respectively. About 57% and 67% of TNP was transferred to BNP in the two grasslands. The turnover rates of aboveground live biomass and belowground biomass in the low elevation grassland were 3.48 and 1.58, respectively and the corresponding values in the high elevation grassland were 1.41. and 1.21. [ABSTRACT FROM AUTHOR]

In view of paramount significance of species diversity to community structure and function, the present study was aimed at a comparative assessment of plant species richness, evenness, and aggregate diversity of the Kashmir Himalayan grasslands occurring at different elevations. Rarefaction method that takes into account nonlinearity of species and area combined with a fitting procedure, and non-parametric estimators were used to compute the expected number of species. All the estimators of species richness used in the present study performed reasonably well, but the ICE (Incidence-based Coverage Estimator) and Chao2 were particularly useful even at low, sampling effort. Highest number of 26 species was recorded in the valley-plain grassland and lowest number of 17 species was recorded in the alpine grassland. Evenness and Shannon index of diversity, due to dominance of the grass Themeda anathera, in the sub-alpine grassland were lowest compared to the valley-plain and alpine grasslands. SHE analysis clearly indicated variable contribution of richness and evenness components to the aggregate measure of species diversity in these grasslands. Computation of the complementary of species composition between the grasslands, analysed through use of the different indices, revealed more or less distinct species assemblages in the grasslands. We suggest that a separate but simultaneous measurement of diversity components using standardized sampling protocols and appropriate diversity estimators, as adopted in the present study, are obligatory for clear understanding and better interpretation of the patterns of plant diversity in the natural plant communities, such as grasslands. [ABSTRACT FROM AUTHOR]

This article focuses on a study which indicates that release from native herbivory together with relief from alien mycorrhizal mutualists synergistically promote invasiveness of an exotic species in Kashmir Himalaya in India. The fast-spreading species of Anthemis cotula, an annual herbacious plant, is emerging as a major threat to the native biodiversity and ecosystem processes in the Himalayan valley of Kashmir.

Ceratophyllum platyacanthum Cham. subsp. oryzetorum (Kom.) Les (Ceratophyllaceae) is recorded for the first time from Kashmir Himalaya and India. The species differs from its closely related taxon, Ceratophyllum demersum, in having smaller leaves and the fruit with a facial spine. A comparison between Ceratophyllum demersum and C. platyacanthum subsp. oryzetorum, and the taxonomic description, photographs and distribution map are provided to facilitate its field identification in the region. [ABSTRACT FROM AUTHOR]