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1.
Proc Biol Sci ; 290(1997): 20222513, 2023 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-37122248

RESUMO

The Western Ghats (WG) mountain chain is a global biodiversity hotspot with high diversity and endemicity of woody plants. The latitudinal breadth of the WG offers an opportunity to determine the evolutionary drivers of latitudinal diversity patterns. We examined the spatial patterns of evolutionary diversity using complementary phylogenetic diversity and endemism measures. To examine if different regions of the WG serve as a museum or cradle of evolutionary diversity, we examined the distribution of 470 species based on distribution modelling and occurrence locations across the entire region. In accordance with the expectation, we found that the southern WG is both a museum and cradle of woody plant evolutionary diversity, as a higher proportion of both old and young evolutionary lineages are restricted to the southern WG. The diversity gradient is likely driven by high geo-climatic stability in the south and phylogenetic niche conservatism for moist and aseasonal sites. This is corroborated by persistent lineage nestedness at almost all evolutionary depths (10-135 million years), and a strong correlation of evolutionary diversity with drought seasonality, precipitation and topographic heterogeneity. Our results highlight the global value of the WG, demonstrating, in particular, the importance of protecting the southern WG-an engine of plant diversification and persistence.


Assuntos
Museus , Madeira , Filogenia , Evolução Biológica , Biodiversidade
2.
Lett Appl Microbiol ; 76(4)2023 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-37115025

RESUMO

Coscinium fenestratum is a medicinally significant critically endangered plant found in Western Ghats of India. The leaf spot and blight was observed in Kerala during 2021 with disease incidence of 40% in 20 assessed plants in 0.6 hectare. The associated fungus was isolated on potato dextrose agar medium. A total of six morpho-culturally identical isolates were isolated and morphologically identified. Based on morpho-cultural features, the fungus was identified at genus level as Lasiodiplodia sp., which was further authentically confirmed as Lasiodiplodia theobromae by molecular identification with a representative isolate (KFRIMCC 089) using multigene (ITS, LSU, SSU, TEF1-α, and TUB2) sequence analysis and concatenated phylogenetic analysis (ITS-TEF1-α-TUB2). Pathogenicity tests were also assessed in vitro and in vivo using mycelial disc and spore suspension of L. theobromae, and the isolated fungus's pathogenic behaviour was confirmed after re-isolation and morpho-cultural features. Literature survey reveals that there are no reports of L. theobromae on C. fenestratum from all over the world. Hence, C. fenestratum is being firstly reported as a new host record for L. theobromae from India.


Assuntos
Ascomicetos , Filogenia , Ascomicetos/genética , Índia , Meios de Cultura
3.
Exp Appl Acarol ; 90(3-4): 429-440, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37347433

RESUMO

The spotted fever group (SFG) of Rickettsia are zoonotic disease-causing pathogens, commonly transmitted by hard ticks to a wide range of hosts, including humans. Rickettsia conorii is the common SFG recognised in India, whereas most of the infections due to other group species go undifferentiated at the species level. Hence, this study was conducted to screen host-seeking ticks in the Western Ghats region, India, for the DNA of SFG Rickettsia. The ticks were collected from Kerala, Goa, and Maharashtra states of India during a survey conducted between November 2017 and January 2018. In total, 288 tick pools were screened for Rickettsia spp. DNA using pan-Rickettsia real-time PCR, and conventional PCR targeting the gltA, OmpA and 17-kDa protein-coding genes. Nucleotide sequences were subjected to phylogenetic analysis using the NCBI BLAST tool to identify submitted sequences with higher homology. Neighbour-joining trees were constructed using the reference sequences of the GenBank database. Overall, Rickettsia spp. DNA was detected in 27.2% (62/228 pools) of host-seeking ticks across the Western Ghats region, with an estimated minimum infection rate of 0.057. Upon phylogenetic analysis, it was identified that the detected sequences were highly similar (> 99% sequence homology) to R. africae, Candidatus R. laoensis and an un-categorised Rickettsia species, and they were widely carried by Haemaphysalis ticks. The current study is the first report of R. africae and Candidatus R. laoensis in ticks in India. Although the pathogenicity of these species is not well documented, they may pose a potential threat to both animal and the human population in this geographical region.


Assuntos
Ixodidae , Rickettsia , Rickettsiose do Grupo da Febre Maculosa , Carrapatos , Animais , Humanos , Carrapatos/microbiologia , Filogenia , Índia , Rickettsia/genética , Ixodidae/microbiologia , Reação em Cadeia da Polimerase em Tempo Real , Rickettsiose do Grupo da Febre Maculosa/epidemiologia , Rickettsiose do Grupo da Febre Maculosa/veterinária
4.
Environ Monit Assess ; 195(12): 1461, 2023 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-37953340

RESUMO

Initial reports signify some specific isolated locations in different latitudes, revealing a paradoxical increase in both heavy and very heavy rainfall events and also an increment in total, i.e., in both rainfall and temperature, over ecologically sensitive areas along the Western Ghats (WG). This paper presents a coherent study of the full-scale of daily rainfall and temperature over 27 well-spaced stations in the study area to determine its extent and investigate whether or not this contradictory behaviour is real. Also, an attempt has been made to assess the differential behaviour of rainfall, temperature, and heavy rainfall events in association with land use and land cover change (LULC). The analysis revealed that rainfall and temperature over the study area are increasing, whereas heavy rainfall events have increased during 1981-2020 with strong peaks after 2000 around 18-19°N (Mumbai metropolitan region), 14-16°N (mining and quarrying regions in Goa), and 9-12°N (a narrow strip of land spanning across the coastal towns of Karnataka and Kerala) latitudes. The majority of the rainfall excess years coincided with El Nino years, indicating that El Nino does not affect rainfall negatively. However, rainfall over the WG is influenced by local relief and cascading topography. The spatial pattern of average annual rainfall shows a decreasing trend from south to north because the elevation and span of rainfall occurrence are higher in the southern part of WG. The findings of the current research will help in building a strategy to address trends and patterns of climatic variables in association with LULC.


Assuntos
El Niño Oscilação Sul , Monitoramento Ambiental , Temperatura , Índia
5.
Environ Monit Assess ; 195(5): 578, 2023 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-37062766

RESUMO

The effect of climate change on the tropical river catchments in the Western Ghats of India is studied using the Coupled Model Intercomparison Project-6 data (CMIP-6). Multi-model ensembles of rainfall and temperature are constructed using the Random Forest ensemble technique for bias-corrected GCMs in the near future (2014-2050) and far future (2051-2100) horizons. For the two catchments each in the southern, central, and northern Ghats, the trend in minimum and maximum temperatures, precipitation, and other indices are calculated. By 2100, dry sub-humid and humid catchments will see a higher increase in mean annual temperature than per-humid central catchments. In future decades, the warm days and nights increase by 45-50% and 40-70%, respectively, with twofold warming in the winter season. Under a climate change scenario, annual rainfall increases in Vamanapuram, Ulhas, and Purna, while Chaliyar, Netravati, and Aghanashini catchments experience a decrease in rainfall in the far future with an increase in pre-monsoon rainfall. The southern catchments are anticipated to have contrasting variations in the rainfall extremes; northern catchments face a substantial increase in very wet to extremely wet days and medium to heavy rainfall. In all catchments (excluding Vamanapuram), cumulative wet days increase with a decrease in cumulative dry days. After the mid-twenty-first century, humid to per-humid catchments encompass an increase in cool nights, whereas it disappears in dry sub-humid catchments of the Ghat. Interestingly, warming tendencies begin to slow down after 2050. This investigation can assist in comprehending the regional climate extremes in the Western Ghats to formulate better climate risk planning and adaptation strategies.


Assuntos
Monitoramento Ambiental , Rios , Estações do Ano , Temperatura , Índia , Mudança Climática
6.
Agrofor Syst ; 97(5): 751-783, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37193256

RESUMO

Homegarden (HG) agroforestry combines biological carbon (C) sequestration with biodiversity conservation outcomes. Although C stocks and species richness of HGs vary along elevational gradients and as a function of holding sizes, there is no consensus on the nature and magnitude of such variations. Field studies were conducted in the Western Ghats region of central Kerala, India (180 homesteads in 20 selected panchayats), to evaluate the effects of elevation (near sea level to 1938 m) and garden size (162-10,117 m2) on aboveground C stocks and floristic diversity. The C stocks (per unit area) of HGs (arborescent species) were highly variable (0.63-93.65 Mg ha-1), as garden management was highly individualistic and it exhibited a weak negative relationship with elevation. Likewise, there was a weak negative relationship between C stocks and garden size. Tree stocking levels (stems/garden) and species richness (species/garden) positively impacted total C stocks per garden. Floristic diversity was high in the study area (753 species) and included many rare and endangered species (43 IUCN Red-Listed species) making homegardens circa situm reservoirs of biodiversity. Elevation and holding size exerted a weak negative linear relationship on Simpson's floristic diversity index, which ranged from 0.26 to 0.93 for the arboreal species. Homegardens, regardless of elevation or size, contribute to C sequestration and agrobiodiversity conservation and help achieve the UN Sustainable Development Goals (SDGs), particularly Climate Action (SDG-13) and conserving agrobiodiversity (SDG-15, Life on Land).

7.
Mol Phylogenet Evol ; 175: 107495, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35569808

RESUMO

The tropical forests of the Western Ghats (WG) of India are considered 'refugia' harbouring highly diverse and endemic taxa but these refugia are under immense anthropogenic pressure. Most phylogenetic studies have explained diversity patterns across the WG using vertebrates, however, the processes impacting the highly endemic invertebrate fauna are still poorly understood. Here we investigate the evolutionary history of an ancient and widespread arachnid lineage (Pseudoscorpiones: Chthoniidae: Tyrannochthoniini) in the WG through a variety of biogeographical and diversification analyses, including sequence data from three markers for 45 terminals from the WG and 22 from Africa, East and Southeast Asia, Australasia and the Neotropics. Our results show that WG Tyrannochthoniini are rendered paraphyletic by African taxa, a result consistent with continental drift. WG Tyrannochthoniini are further split into two major clades, a southern WG clade and an African-central WG clade, due to vicariance along a major biogeographical barrier, the Palghat Gap. Central WG pseudoscorpions diverged from their African relatives at the Jurassic-Cretaceous boundary, coinciding with the separation of India from Africa. Despite ancient vicariance, six dispersal events occurred across the Palghat Gap, beginning in the Early Cretaceous as India was rafting towards Southeast Asia and ending by the early Miocene, implying that the Palghat Gap became impermeable to dispersal for these humid-adapted organisms during Miocene aridification. Although the ancestor of WG Tyrannochthoniini originated in lowland WG forests, three dispersal events into high montane Shola forests occurred most likely as a result of Late Cretaceous orogenesis and Neogene uplift, allowing lineages to occupy niches at higher elevations. An exponentially declining diversification rate, typical of older lineages, supports the 'museum' model of diversification for WG Tyrannochthoniini. Our study sheds light on the historical biogeography of relictual soil-arthropods in the WG and emphasises the role of WG forest refugia in preserving ancient invertebrate biodiversity.


Assuntos
Aracnídeos , Biodiversidade , Animais , Evolução Biológica , Florestas , Filogenia , Filogeografia
8.
Mol Phylogenet Evol ; 165: 107300, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34474153

RESUMO

In widespread species, the diverse ecological conditions in which the populations occur, and the presence of many potential geographical barriers through their range are expected to have created ample opportunities for the evolution of distinct, often cryptic lineages. In this work, we tested for species boundaries in one such widespread species, the king cobra, Ophiophagus hannah (Cantor, 1836), a largely tropical elapid snake distributed across the Oriental realm. Based on extensive geographical sampling across most of the range of the species, we initially tested for candidate species (CS) using Maximum-Likelihood analysis of mitochondrial genes. We then tested the resulting CS using both morphological data and sequences of three single-copy nuclear genes. We used snapclust to determine the optimal number of clusters in the nuclear dataset, and Bayesian Phylogenetics and Phylogeography (BPP) to test for likely species status. We used non-metric multidimensional scaling (nMDS) analysis for discerning morphological separation. We recovered four independently evolving, geographically separated lineages that we consider Confirmed Candidate Species: (1) Western Ghats lineage; (2) Indo-Chinese lineage (3) Indo-Malayan lineage; (4) Luzon Island lineage, in the Philippine Archipelago. We discuss patterns of lineage divergence, particularly in the context of low morphological divergence, and the conservation implications of recognizing several endemic king cobra lineages.


Assuntos
DNA , Ophiophagus hannah , Animais , Teorema de Bayes , Filipinas , Filogenia , Piridazinas
9.
Biol Lett ; 17(8): 20210212, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34343438

RESUMO

The Indian subcontinent has an origin geologically different from Eurasia, but many terrestrial animal and plant species on it have congeneric or sister species in other parts of Asia, especially in the Southeast. This faunal and floral similarity between India and Southeast Asia is explained by either of the two biogeographic scenarios, 'into-India' or 'out-of-India'. Phylogenies based on complete mitochondrial genomes and five nuclear genes were undertaken for ricefishes (Adrianichthyidae) to examine which of these two biogeographic scenarios fits better. We found that Oryzias setnai, the only adrianichthyid distributed in and endemic to the Western Ghats, a mountain range running parallel to the western coast of the Indian subcontinent, is sister to all other adrianichthyids from eastern India and Southeast-East Asia. Divergence time estimates and ancestral area reconstructions reveal that this western Indian species diverged in the late Mesozoic during the northward drift of the Indian subcontinent. These findings indicate that adrianichthyids dispersed eastward 'out-of-India' after the collision of the Indian subcontinent with Eurasia, and subsequently diversified in Southeast-East Asia. A review of geographic distributions of 'out-of-India' taxa reveals that they may have largely fuelled or modified the biodiversity of Eurasia.


Assuntos
Oryzias , Animais , Sudeste Asiático , Biodiversidade , Índia , Filogenia
10.
J Environ Manage ; 280: 111759, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33298397

RESUMO

Tropical montane grasslands (TMG) support biodiverse and endemic taxa and provide vital ecosystem services to downstream communities. Nevertheless, invasive alien tree species across the world have threatened tropical grasslands and grassland endemic species. In India, TMG in the Shola Sky Islands of the Western Ghats have been reduced due to exotic tree invasions (Acacias, Pines, and Eucalyptus species). The loss of grassland habitat has, in turn, reduced the range sizes of species endemic to grasslands (plants, birds, amphibians, and mammals), driving some populations to local extinction. Grassland conversion to exotic trees has also impacted ecosystem services in the Western Ghats. Conserving existing grassland and restoring invaded habitat is critical to reverse these losses. This research focused on identifying grassland restoration sites using satellite images with a high spatial resolution (RapidEye). We used an object-oriented Random Forest classification to map the area for grassland restoration. We identified an area of 254 sq. km. as suitable for grassland restoration and an area of 362 sq. km. for grassland conservation and preventing invasion by exotic tree species. For restoration, we recommend careful removal of young and isolated exotic trees at the invasion front and restoring grasslands, instead of removing dense stands of mature exotic trees. Although our limited data indicate that areas with low fire frequency tend to be invaded, and areas invaded by exotic trees tend to burn at higher intensities, we recommend a broader investigation of these patterns to critically examine a potential role for the use of fire in invasive species management. We assume that removing exotic tree species in the identified restoration sites and restoring the grassland will help recover lost habitat and ensure the viability of indigenous and endemic species and increase streamflow.


Assuntos
Espécies Introduzidas , Árvores , Animais , Biodiversidade , Ecossistema , Pradaria , Índia , Ilhas , Tecnologia de Sensoriamento Remoto
11.
Environ Monit Assess ; 193(12): 820, 2021 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-34792670

RESUMO

This paper assesses the long-term combined effects of land use (LU) and climate change on river hydrology and water scarcity of two rivers of the Western Ghats of India. The historical LU changes were studied for four decades (1988-2016) using the maximum likelihood algorithm and the long-term LU (2016-2075) was estimated using the Dyna-CLUE prediction model. Five General Circulation Models (GCMs) were utilized to assess the effects of climate change (CC) and the Soil and Water Assessment Tool (SWAT) model was used for hydrological modeling of the two river catchments. To characterize granular effects of LU and CC on regional hydrology, a scenario approach was adopted and three scenarios depicting near-future (2006-2040), mid-future (2041-2070), and far-future (2071-2100) based on climate were established. The present rate of LU change indicated a reduction in forest cover by 20% and an increase in urbanized areas by 9.5% between 1988 and 2016. It was estimated that forest cover in the catchments may be expected to halve compared to the present-day LU (55% in 2016 to 23% in 2075), along with large-scale conversion to agricultural lands (13.5% in 2016 to 49.5% in 2075). As a result of changes to LU and forecasted climate, it was found that rivers in the Western Ghats of India might face scarcity of fresh water in the next two decades until the year 2040. However, because of large-scale LU conversion toward the year 2050, streamflow in rivers might increase as high as 70.94% at certain times of the year. Although an increase in streamflow is perceived favorable, the streamflow changes during summer and winter may be expected to affect the cropping calendar and crop yield. The changes to streamflow were also linked to a 4.2% increase in ecologically sensitive wetlands of the Aghanashini river catchment.


Assuntos
Mudança Climática , Rios , Monitoramento Ambiental , Hidrologia , Índia , Insegurança Hídrica
12.
Helminthologia ; 58(3): 292-314, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34934392

RESUMO

Two new and two known species of the genus Paraoxydirus Jairajpuri and Ahmad, 1978 are described and illustrated from Western Ghats of India. P. vulvalpapillatus n. sp. is characterized by having large sized body (L = 4.6 - 4.8 mm); lip region continuous with completely amalgamated lips; amphidial fovea cup - shaped; 5 - 6 µm long odontostyle; 11 - 13 µm long odontophore; pharyngeal expansion about 28 - 36 % of neck length; transverse vulva; vulval papillae conspicuous; males with 46 - 54 µm long spicules; 11 - 14 continuous ventromedian supplements and long filiform tail similar in both sexes. P. indicus n. sp. is characterized by having large sized body (L = 4.0 - 4.8 mm); lip region poorly offset with amalgamated lips; amphidial fovea cup-shaped; 7 - 8 µm long, robust odontostyle; 17 - 18 µm long odontophore; pharyngeal expansion about 32 - 40 % of neck length; 21 - 26 µm long cardia; longitudinal vulva; 748 - 894 µm long filiform tail; males with 45 - 54 µm long spicules and 12 - 15 continuous ventromedian supplements. P. gigas Jairajpuri, 1964 and P. novus Jairajpuri, 1965 are redescribed based on specimens collected from several localities. A diagnostic Key and compendium to the identification of its eight valid species is provided.

13.
Plant Foods Hum Nutr ; 75(4): 659-660, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32820430

RESUMO

Wild jack (Artocarpus hirsutus Lam.) is an endemic perennial tree of Western Ghats of India. Wild jack, a timber purpose tree, is distributed in several Kaan community forests. Although local people consume unripe as well as fully ripe fruits and roasted seeds, wild jack is unrecognized as a fruit tree. It remains almost undocumented with respect to nutritional value in terms of biochemical composition. We carried out biochemical profiling of ripe fruits and seeds of wild jack. Every 100 g fruit pulp was composed of 12 g total soluble sugars, 16.7 g total starch, 441 µg total carotenoids (beta carotene equivalent) and 8.1 mg ascorbic acid, 0.4 mg GAE total phenol and showed total cupric reducing antioxidant activity of 1.9 mg gallic acid equivalents (GAE). Every 100 g whole seed flour was composed of 6 g total soluble sugars, 6.6 g starch, 9.9 g total proteins, 3 mg GAE total phenol and 3.1 mg GAE total antioxidant capacity. Biochemical profiles of wild jackfruit and seeds were comparable with those of other Artocarpus fruits like jackfruit and bread fruit. Our findings suggest that wild jack deserves to be promoted as a minor fruit species of high nutritional importance and must be considered as a potential fruit crop species for further research.


Assuntos
Artocarpus , Antioxidantes , Frutas , Fenóis , Sementes
14.
Trop Ecol ; 61(4): 570-582, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33041475

RESUMO

Salim Ali's fruit bat, Latidens salimalii, is a monotypic endangered fruit bat endemic to Western Ghats (WG) with an ambiguous distribution. The distribution range, habitat suitability, and biology of this species are still uncertain. Endemic species inhabiting the high elevation of  WG like L. salimalii are threatened due to climatic change and seeks urgent management interventions. Hence, we developed a habitat suitability model for L. salimalii using MaxEnt in the current climate condition and projected their distribution for three Representation Concentration Pathway (RCP 4.5, 6.0, and 8.5) climate scenarios of the 2070 time frame. The results show that 9531 km2of habitat in WG is suitable for L. salimalii at present, while all the future scenarios estimates propose complete loss of highly suitable habitat. The significant factors influencing the distribution of L. salimalii are the precipitation of the driest month, tree density, rain in the coldest quarter, canopy height, and altitude. The study pioneers in predicting the suitable habitat and emphasis the need to develop strategies for the long-term conservation of endangered L. salimalii in WG under global warming scenarios.

15.
Mol Phylogenet Evol ; 138: 102-113, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31132521

RESUMO

The evolution of Peninsular Indian biodiversity has been a fascinating topic of research due to historical connections of this region to the ancient Gondwanaland. We investigated the phylogeny and historical biogeography of nearly all extant species of the genus Piper reported from the region to assess the biogeographical origins and test mechanisms of lineage diversification (dispersal, vicariance and in situ radiation) of this highly diverse genus of angiosperms commonly found in the understory of evergreen forests. The phylogeny of 21 species of Piper reported from Peninsular India was reconstructed for the first time, which included three new putative species from the Western Ghats. We used BEAST for the divergence time estimations (using three constraints), and ancestral range estimations were performed with the dated phylogenetic tree using BIOGEOBEARS. Divergence dating analysis revealed that the genus Piper originated during lower Cretaceous around 110 Ma [95% highest posterior density (HPD): 116-105 Ma] and colonized Peninsular India five times independently, from Southeast Asia starting from the Oligocene. The two major dispersals into India occurred during the periods of 27.3 Ma (95% HPD: 35.8-19.9.) and 15.5 Ma (95% HPD: 24.9-7.11). This was followed by rapid radiations in some lineages with subsequent back dispersals to Southeast Asia. Our study indicates that dispersals from Southeast Asia led to the arrival of Piper to Indian subcontinent following the Indo-Eurasian collision. Members of Piper have colonized and diversified within the climatically stable habitats of Peninsular India. Furthermore, the present study provides evidence for the Miocene overland dispersal of Piper species to Africa from South Asia.


Assuntos
Evolução Biológica , Piper/genética , Biodiversidade , Índia , Filogenia , Filogeografia , Piper/classificação , Fatores de Tempo
16.
Microb Pathog ; 135: 103624, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31323321

RESUMO

A study was conducted to isolate and characterize endophytes from Artemisia nilagirica, a traditional medicinal plant. The plant was collected from Western Ghats, India. Endophytes isolated included Arthrobacter sp. WWAT1, Pseudomonas sp. WYAT2, Microbacterium sp. WYAT3, Psychrobacter sp. WBAT4, Enterobacter sp. WWAT5, Bacillus sp. WBAT6, Kosakonia cowanii WBAT7, Bacillus sp. WBAT8, Bacillus sp. WBAT9, Chromobacterium violaceum WVAT6, Serratia sp.WPAT8 and Burkholderia sp. WYAT7. Of these two bacteria, Chromobacterium violaceum strain WVAT6 and Burkholderia sp. strain WYAT exhibited antibacterial property against human pathogens. Similar to the environmental isolates, Burkholderia sp. WYAT7 showed pleomorphism and produced different enzymes, whereas like clinical strains they showed multidrug resistance, for their survival in different environmental conditions. Chromobacterium violaceum WVAT6 exhibited rod shape morphology and showed multiple drug resistance except to erythromycin, tetracycline and gentamicin antibiotics. Both produced biofilm and enzymes such as protease and lipase. The antimicrobial compounds from these endophytes may find application in the preparation of antimicrobial formulations.


Assuntos
Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Artemisia/microbiologia , Endófitos/isolamento & purificação , Endófitos/metabolismo , Bactérias/efeitos dos fármacos , Biofilmes , Burkholderia/isolamento & purificação , Burkholderia/metabolismo , Chromobacterium/isolamento & purificação , Chromobacterium/metabolismo , DNA Ribossômico , Endófitos/classificação , Endófitos/genética , Humanos , Índia , Lipase/metabolismo , Testes de Sensibilidade Microbiana , Peptídeo Hidrolases/metabolismo , Filogenia , Plantas Medicinais
17.
Ecol Appl ; 29(8): e01996, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31495013

RESUMO

Edge effects can alter the spatial organization of diversity in fragmented habitats. For tropical forests, however, there has been large variation in the strength and direction of such effects reported by different studies. For long-lived organisms like trees, one reason for inconsistent patterns might be due to most studies having examined patterns of diversity and compositional variation in older life stages that bear the legacy of a forest past. Younger life stages can reveal ongoing processes of assembly, but multi-stage examinations are rare. For seedling, sapling, and adult life stages of trees in a human-modified wet tropical forest in the Western Ghats Biodiversity Hotspot (India), we examined how proximity to forest edges (edge influence) modified the spatial organization of diversity. Specifically, for each life stage we tested whether edge influence led to loss of α- and γ-diversity and decreased ß-diversity in this landscape. We found lower α- and γ-diversity closer to forest edges, but only for seedlings. Seedling composition at 90-100 m from forest edges diverged from composition of sites within 60 m, suggesting that edge influence restricted the recruitment of some species to interior sites. In contrast, ß-diversity was greater near edges than interior forest for all life stages and most prominently for seedlings. Furthermore, ß-diversity at edges was primarily driven by species turnover, suggesting either marked species-environment associations or dispersal limitation. Low turnover at 90-100 m implies that ß-diversity arose from stochastic fluctuations in occurrences and abundances of the same species set. Overall, we find that high ß-diversity structured spatial patterns of diversity near edges, but recruitment bottlenecks are likely to reduce alpha diversity of forest fragments. Our results also corroborate the need to maintain sufficiently large areas of tropical forest free from edge effects to avoid the loss of interior forest species. To improve landscape-scale diversity of fragmented landscapes, restoration efforts should focus on recovery of species that are unable to regenerate near forest edges.


Assuntos
Florestas , Árvores , Idoso , Biodiversidade , Ecossistema , Humanos , Índia , Clima Tropical
18.
Environ Monit Assess ; 191(11): 690, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31664599

RESUMO

Sequestration of atmospheric carbon-dioxide in biospheric carbon (C) pools is a key strategy towards climate change mitigation. Soil is a huge C reservoir and its storage potential varies greatly with forest types. Therefore, in the present study, the soil organic carbon (SOC) storage pattern was assessed from 70 plots laid at three selected forest types comprising seven study sites at Kanyakumari Wildlife Sanctuary, Western Ghats, India: tropical dry deciduous (TDD I and TDD II), tropical semi-evergreen (TSE I and TSE II) and tropical evergreen forest (TEF I, TEF II and TEF III) at three depths (0-10, 10.1-20 and 20.1-30 cm). Statistical analyses were performed to understand the relationships between SOC stocks with other predictor variables. The SOC stock varied markedly with forest type and site-wise. The SOC ranged from 58 (TEF III) to 123.6 (TDD I) Mg C/ha with a mean of 84.9 ± 4.4 Mg C/ha at 0-30 cm depth. SOC stock decreased, while soil bulk density increased with increase in soil depth. The TDD forest type (115.6 Mg C/ha) stocked the highest SOC compared to TEF (75.1 Mg C/ha) and TSE (68.9 Mg C/ha) forest types. Of the total SOC stock (0-30 cm), 44.2, 32.0 and 23.8% were stored in 0-10, 10.1-20 and 20.1-30 cm respectively in all the forest types. In contrast, litter C stock were high in TEF and TSE forest types and low in TDD forest type. SOC showed significant (P < 0.01) negative relationships with bulk density, litter C, and vegetation attributes. The SOC stock stored in the study sites amount to 212.9 (TEF III) to 453.6 (TDD I) Mg of CO2 equivalents. The present study reveals that forest type and site characteristics have a profound impact on SOC stock, which would, in turn, exert a great bearing on the ecosystem C cycling. These results would also enhance our ability to evaluate the role of these forest types in soil C sequestration and for developing and validating SOC models for tropical forest ecosystems.


Assuntos
Sequestro de Carbono , Monitoramento Ambiental , Florestas , Carbono/análise , Ciclo do Carbono , Mudança Climática , Ecossistema , Índia , Solo/química
19.
J Environ Manage ; 206: 1263-1273, 2018 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-28807516

RESUMO

Sedimentation involving the process of silt transport also carries nutrients from upstream to downstream of a river/stream. Sand being one of the important fraction of these sediments is extracted in order to cater infrastructural/housing needs in the region. This communication is based on field research in the Aghanshini river basin, west coast of India. Silt yield in the river basin and the sedimentation rate assessed using empirical techniques supplemented with field quantifications using soundings (SONAR), show the sediment yield of 1105-1367 kilo cum per year and deposition of sediment of 61 (2016) to 71 (2015) cm. Quantifications of extractions at five locations, reveal of over exploitation of sand to an extent of 30% with damages to the breeding ground of fishes, reduced productivity of bivalves, etc., which has affected dependent people's livelihood. This study provides vital insights towards sustainable sand harvesting through stringent management practices.


Assuntos
Estuários , Dióxido de Silício , Animais , Monitoramento Ambiental , Sedimentos Geológicos , Índia , Rios
20.
Exp Appl Acarol ; 75(1): 135-142, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29594846

RESUMO

Kyasanur forest disease (KFD) is a major tick-borne viral haemorrhagic fever caused by KFD virus (KFDV) (Flaviviridae). The disease was reported to be confined to five districts of Karnataka state India until 2011. During 2012-2016, emergence of KFD has been reported in newer areas of Karnataka and adjoining states. Therefore, survey of tick vectors was carried out in these new areas of Karnataka and adjoining states reported with monkey deaths and human cases of KFD. In all selected sites, ticks from the forest floor were collected by lint clothes using flagging method. Tick samples were tested for KFDV nucleic acid by real-time RT-PCR. A total of 4772 ticks, comprising eight species of genus Haemaphysalis and one species each of genus Amblyomma, Ixodes and Rhipicephalus was collected. Haemaphysalis spinigera, the principal vector of KFDV was the predominant tick species (59.5%) collected followed by H. turturis (8.6%). The abundance of H. spinigera ranged from 9.2 to 33.9 per man-hour in the six districts surveyed. Of 214 (4418 tick samples) pools screened by real-time RT-PCR, two pools of H. spinigera were positive for KFDV. High abundance of Haemaphysalis vectors in the six districts indicated that the districts are receptive for KFD outbreaks. KFDV was detected in the tick vectors in the new foci of the KFD. Data on tick distribution will be useful in creating KFD risk map for strengthening the ongoing preventive measures such as vaccination and supply of insect repellents to the high risk groups and intensive health education.


Assuntos
Vetores Aracnídeos/fisiologia , Vetores Aracnídeos/virologia , Ixodidae/fisiologia , Ixodidae/virologia , Doença da Floresta de Kyasanur/epidemiologia , Doenças dos Macacos/mortalidade , Distribuição Animal , Animais , Biodiversidade , Vírus da Encefalite Transmitidos por Carrapatos/isolamento & purificação , Florestas , Humanos , Índia/epidemiologia , Doença da Floresta de Kyasanur/virologia , Densidade Demográfica , Prevalência
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