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Endophytes, both bacterial and fungal, constitute an integral component of the leaf ecosystem. Here we argue that the respiratory metabolism of endophytes in the intercellular spaces of leaves could have a significant role in enhancing leaf photosynthesis by enriching the internal COsub2/subconcentration, especially in C3 plants.

Bacillus velezensis EB14, isolated from a leaf of Populus × jackii, possesses antagonistic activity against Sphaerulina musiva, a fungal pathogen of Populus sp. that causes leaf spots and stem cankers on poplars, limiting the utility of hybrid poplars as plantation trees. We sequenced the genome of B. velezensis EB14 to gain insights into the underlying basis of its antagonistic activity. Here, we report the complete genome sequence of B. velezensis EB14, a gram-positive bacterium of the family Bacillaceae. Through antiSMASH analysis, we predicted several gene clusters coding for the biosynthesis of antimicrobial compounds and several genes involved in plant bacterial interactions. These findings support the potential of developing B. velezensis EB14 as a biocontrol agent against S. musiva in poplar plantations. The genome of B. velezensis EB14 along with genome sequences of closely related B. velezensis species are invaluable for comparative genomic analyses to gain insights into bacterial, fungal, and host plant interactions.

Sclerotium rolfsii is a necrotrophic, soil-borne pathogenic fungus responsible for serious crop losses worldwide. It is one of the major phytopathogens infecting chilli and causes yield losses ranging from 16 to 80%. Among the various approaches to manage S. rolfsii, biological control is an environmentally acceptable alternative over other chemical methods. In this study, 120 endophytic fungal isolates obtained from a medicinal plant, Nothapodytes nimmoniana were evaluated for their in vitro and in vivo antagonism towards S. rolfsii. Among these, one isolate, Alternaria sp. exhibited 46.62% inhibition against S. rolfsii in dual culture assay on PDA. The inhibition was found to be mediated by the mycotoxin, tenuazonic acid, produced by the endophyte. Pre-germinated chilli seeds treated with mycelial suspension of Alternaria sp. reduced the seedling mortality due to S. rolfsii infection. Pretreatment with the endophyte also enhanced seedling growth and biomass compared to untreated seedlings under greenhouse conditions. These results suggest that the endophytic fungus, Alternaria sp. has potential implication for use as a biocontrol against S. rolfsii as well as for promoting growth of chilli.

Alternative splicing (AS) of transcripts is a well-recognized phenomenon in plants. Several studies have shown that the frequency of AS events are significantly enhanced in plants subjected to abiotic stresses, presumably as an adaptation to increase transcript diversity. In this study, we examine the effect of a salt tolerant endophytic fungus, Fusarium sp. on the AS events of IR-64 rice plants, under salinity stress. RNA seq data generated from rice plants, treated and not treated with Fusarium sp. respectively and subjected to 150 mM salinity stress was used to analyze the number and type of AS events and their chromosomal distribution using approriate bioinformatics pipeline. Besides, we also annotated the locus IDs of genes for gene enrichment and KEGG pathway analysis. Our results show an unequivocal decrease in the number of AS events under salinity stress as influenced by the endophyte. The average AS events per gene also decreased from 2.28 to 2.11 upon colonization by the endophyte. This is the first documented evidence of an endophyte-induced alteration in the frequency of alternative splicing event in plants subjected to salinity stress. The exact mechanisms through which the splicing activities are restrained, however need to be further investigated.

Endophytes are non-disease causing microbes (bacteria and fungi) surviving in living tissues of plants. Their intimate association and possible coevolution with their plant partners have resulted in them contributing to an array of plant growth benefits ranging from enhanced growth and biomass accumulation, tolerance to abiotic and biotic stresses and in nutrient acquisition. The last couple of decades have witnessed a burgeoning literature on the role of endophytes (Class 3 type) in regulating plant growth and development and their adaptation to abiotic and biotic stresses. Though the underlying mechanisms of plant-endophyte interactions are far from clear, several studies have raised the hope of their potential application in agriculture, especially in mitigating abiotic and biotic stresses. The use of endophytes is envisaged as a route to reduce the production cost and burden on the environment by lessening the dependence on breeding for crop improvement and agrochemicals. Unfortunately, save a few well documented examples of their use, a little of these insights has been translated into actual agricultural applications. Here, we reflect on this paucity and elaborate on some of the important bottlenecks that might stand in way of fully realizing the potential that endophytes hold for crop improvement. We stress the need to study various facets of the endophyte-plant association for their gainful application in agriculture.

Rapid climate change threatens plant communities. While many studies address the impact of climate change on plants and mechanisms of their resilience to climate stressors, the role of the plant microbiome in aiding plants' adaptation to climate change has been less investigated. We argue here that fungal endophytes, an important constituent of the plant microbiome, may be key to the ability of plants to adapt to climatic stressors. The rapid adaptive response of endophytes coupled with their ability to ‘transfer’ resistance to their hosts may fast-track plants' adaptation to climate change. We briefly review the importance of Class 3 fungal endophytes of terrestrial plants and discuss how they may accelerate adaptations to climate change in crops and natural plant communities and call for efforts directed at improving the understanding of fungal endophyte-facilitated plant health. Such information could aid in devising improved strategies for mitigating climate change effects on plant communities.

Medicinal plants and their products have been used virtually in all cultures as a source of medicine since time immemorial. In India, several plant species are used as a medicine and in recent years, the trade-in medicinal plants have increased several folds. However, with burgeoning demand for raw herbal products, there has been concern over the safety and efficacy of raw herbal material as well as herbal products that contain only the desired plant species or labeled plant's product. In the present investigation, an emphasis was made to evaluate the extent of species adulteration in the raw herbal trade of Momordica charantia which is commonly called “karela” and used as alternate herbal medicine in the treatment of type-2 diabetes in south India. DNA barcodes were developed for six authentic reference species of Momordica and for the eighteen samples purchased from major raw herbal material distributors of south India representing the raw herbal products of M. charantia sold as “karela” in India. The DNA barcodes were developed using the nuclear region of the internal transcribed spacer (ITS) and the chloroplast region matK of six Momordica species, the biological reference standard, and the raw herbal drug trade samples. The species-level authenticity of the herbal drug samples was assessed adopting two identification methods namely BLAST similarity-based identification and phylogenetic tree approach. Our results indicate that the market samples sold were mostly authentic M. charantia except three. The present study offers a novel and reliable DNA barcode sequence-based approach for screening the species authenticity of raw herbal drug market samples of M. charantia and we have discussed the implications of the study in the larger context of authentication in raw herbal trade.

Rauvolfia tetraphylla L. (family Apocynaceae), often referred to as the wild snakeroot plant, is an important medicinal plant and produces a number of indole alkaloids in its seeds and roots. The plant is often used as a substitute for Ravuolfia serpentine (L.) Benth. ex Kurz known commonly as the Indian snakeroot plant or sarphagandha in the preparation of Ayurvedic formulations for a range of diseases including hypertension. In this study, we examine the spatial localization of the various indole alkaloids in developing fruits and plants of R. tetraphylla using desorption electrospray ionization mass spectrometry imaging (DESI-MSI). A semi-quantitative analysis of the various indole alkaloids was performed using UPLC-ESI/MS. DESI-MS images showed that the distribution of ajmalcine, yohimbine, demethyl serpentine and mitoridine are largely localized in the fruit coat while that for ajmaline is restricted to mesocarp of the fruit. At a whole plant level, the ESI-MS intensities of many of the ions were highest in the roots and lesser in the shoot region. Within the root tissue, except sarpagine and ajmalcine, all other indole alkaloids occurred in the epidermal and cortex tissues. In leaves, only serpentine, ajmalcine, reserpiline and yohimbine were present. Serpentine was restricted to the petiolar region of leaves. Principal component analysis based on the presence of the indole alkaloids, clearly separated the four tissues (stem, leaves, root and fruits) into distinct clusters. In summary, the DESI-MSI results indicated a clear tissue localization of the various indole alkaloids, in fruits, leaves and roots of R. tetraphylla. While it is not clear of how such localization is attained, we discuss the possible pathways of indole alkaloid biosynthesis and translocation during fruit and seedling development in R. tetraphylla. We also briefly discuss the functional significance of the spatial patterns in distribution of metabolites.

In nature, plants and microorganisms interact constantly to modulate their growth and development. The interaction could be beneficial or hostile. Plants are constantly exposed to a range of pathogens, and have evolved mechanisms to fight the pathogen infections with the help of complex networking pathways. In addition to the pathogens, many beneficial organisms such as endophytes, of both, bacterial and fungal origin, are ubiquitously present in all plants. Unlike from their pathogenic counterparts, the endophytes do not cause any disease symptoms in their host plants. Some of the recent scientific discoveries and views concerning plant–microbe interactions are presented here.

Influence of genetic dissimilarity among teak (Tectona grandis Linn. f.) clones on flowering synchrony was studied in a Clonal Seed Orchard (CSO) of teak in Karnataka, Southern India. Flowering phenology was monitored for all the 24 teak clones of the CSO and flowering synchrony between clones was assessed adopting a novel ‘overlap index’. Genetic dissimilarity among these clones was assessed adopting DNA based ISSR (Inter Simple Sequence Repeats) analysis. Large variation in the time of ‘flower initiation’ and of ‘peak flowering initiation’ was observed among the clones belonging to diverse sources, suggesting large asynchronous flowering. Cluster analysis based on ISSR marker indicated that the clones originating from a same source clustered together and there was a clear segregation based on their origin. Correlation analysis revealed a significant negative association between the average Jaccards’s dissimilarity index between pairs of clones and average peak flowering overlap index. Clones from geographically diverse regions had high genetic dissimilarity and also showed high flowering asynchrony within them.

Aims Nothapodytes nimmoniana (Family Icacinaceae) is a deciduous tree species distributed in Asia facing severe population decline. Wood chips from the tree are a source of camptothecin, a globally soughtafter alkaloid with cancer-treating properties, and are harvested unsustainably in natural forests. We studied the pollination ecology of the species and asked if there are constraints in pollination and fruiting success in its natural populations. We also discuss the potential effects of wood extraction on pollinators and reproductive success in the population. Methods The study was carried out during the flowering season in two populations with varying exploitation levels, both located in the Protected Area Network in the Western Ghats of Karnataka State. We assessed floral resource availability and measured pollinator diversity and activity in the canopy from the perspective of the biology of the species. We quantified pollinator abundance and percent fruit set as a function of population density. Important Findings Flowers belong to the fly pollination syndrome and are open to visits by generalists such as Apis dorsata and Trigona iridipennis. Fruiting success did not vary between exploited and unexploited sites, but there was a significant difference in pollinator assemblage. In a lean male flowering year, fruit set was low, suggesting pollen limitation in the population. No fruiting was recorded in the second year at the site where trees were felled soon after the flowering period. We argue that when male floral resources are altered in exploited populations, pollinators of generalist nature may show a shift in foraging pattern. Also, generalist plants may be as susceptible to pollination loss as are specialist plants. The need for outcrossing in the species would probably exacerbate this vulnerability.

Rohitukine, a chromone alkaloid, possesses anti-inflammatory, anti-cancer and immuno-modulatory properties. It has been reported from four species, belonging to the families, Meliaceae and Rubiaceae. Stem bark of Dysoxylum binectariferum (Meliaceae) accumulates the highest amount of rohitukine (3-7% by dry weight). In this study, we examine the spatial and temporal distribution of rohitukine and related compounds during various stages of seed development in D. binectariferum using desorption electrospray ionization mass spectrometry imaging (DESI MSI). Rohitukine (m/z 306.2) accumulation increased from early seed development to seed maturity stage. The spatial distribution of rohitukine was largely restricted to the cotyledonary tissue followed by the embryo and least in the seed coat. Besides rohitukine, rohitukine acetate (m/z 348.2) and glycosylated rohitukine (m/z 468.2) were also detected, both through mass fragmentation and exact mass analysis through Orbitrap mass spectrometry. These results indicate a dynamic pattern of chromane alkaloid accumulation through seed development in D. binectariferum. � 2015 Elsevier Ltd. All rights reserved.

Dalbergia sissoo, a wind-dispersed tropical tree, exhibits high intrafruit seed abortion. Of the four to five ovules in the flower, generally one and occasionally two or three develop to maturity. It has been proposed that the seed abortion is a consequence of intense sibling competition for maternal resources and that this competition occurs as an inverse function of the genetic relatedness among the developing seeds. Accordingly, developing seeds compete intensely when they are genetically less related but tend to develop together when genetically more related. We tested this hypothesis by comparing the genetic similarity among the pairs of seeds developing within a pod with that among (a) random pairs from the pool of all seeds, (b) random pairs from single-seeded pods, and (c) random pairs from two-seeded pods, using both randomly amplified polymorphic DNA (RAPD) and isozymes in five trees. We found that the pairs of seeds developing within a pod are genetically more similar than any random pairs of seeds in a tree. Thus the formation of two-seeded pods appear to be associated with increased genetic relatedness among the developing seeds. We discuss the results in the context of possible fitness advantages and then discuss the possible mechanisms that promote tolerance among related seeds.

In Pongamia pinnata only one of the two ovules develops into a seed in most of the pods. Since pollen was not found to be limiting and reduced fertilization could not completely explain the observed frequency of seed abortion, it implied an effect of postfertilization factors. Aqueous extracts of developing seeds and maternal tissue (placenta) did not influence abortion in vitro, suggesting that abortion may not be mediated by a chemical. Experimental uptake of 14C sucrose in vitro indicated that both the stigmatic and the peduncular seed have similar inherent capacities of drawing resources, but the peduncular seed is deprived of resources in the presence of the stigmatic seed. This deprivation of the peduncular seed could be offset by supplying an excess of hormones leading to the subsequent formation of two seeds in a pod. The prevalence of single-seeded pods in P. pinnata seems therefore to be a result of competition between the two seeds for maternal resources. The evolutionary significance of single-seeded pods in P. pinnata is discussed with respect to possible dispersal advantage enjoyed by such pods.

Dalbergia sissoo, a tropical tree with wind-dispersed pods, exhibits a highly positively skewed distribution of seeds per pod with predominantly only one of the four or five ovules maturing into seed. The abortion cannot be attributed to lack of pollen or resources. This study examines the hypothesis that the abortion is due to an intense rivalry among the developing sibs to gain dispersal advantage. Aqueous extract of the dominant embryos at the stigmatic end that generally develop to maturity significantly inhibited the uptake of labelled sucrose by the young developing (subject) embryos in an in vitro assay system. Extracts of tissues such as subordinate (peduncular embryos), unfertilized ovules and pod coat did not cause such inhibition. Aqueous diffusate of dominant embryos also inhibited the uptake of labelled sucrose by subject embryos. The chemical substance responsible for the inhibition appears to be heat-stable and non-proteinaceous. HPLC analysis indicated the presence of two retention time peaks, different from that of standard indole acetic acid, but with considerable overlap. We hypothesize that the compound could be an indole derivative. We propose that the stigmatic embryos have a head start due to earlier fertilization and produce a chemical that either directly (by metabolically killing) or indirectly (by preventing the uptake of assimilates) kills the proximally placed peduncular embryos.

Sustainable extraction of non-timber forest products (NTFPs) has recently gained considerable attention as a means to enhance rural incomes and conserve tropical forests. However, there is little information on the amounts of products collected per unit area and the impact of extraction on forest structure and composition. In this paper we estimate the quantities of selected products gathered by the Soligas, the indigenous people in the Biligiri Rangaswamy Temple (BRT) sanctuary in Karnataka, India, and examine the effect of extraction on forest structure and composition. Two sites, distant (DS) and proximal (PS), were identified based on the proximity to a Soliga settlement. The frequency of different size classes indicates that regeneration overall is poor in the area. The two sites show differences in species richness, basal area, and tree mortality. Furthermore, non-timber forest product species show a greater deficit of small size classes than the timber forest species, suggesting that regeneration is affected by collection of seeds and fruits from non-timber forest product species. Regeneration, however, may also be affected by other anthropogenic pressures such as fire, grazing and competition with weeds.

Sustainable extraction of non-timber forest products (NTFPs) depends upon harvesting a small fraction of the total productivity. Over-exploitation can lead to a loss of biodiversity, but a low level of extraction, without value addition at the point of origin, is usually not economically feasible for extractors. Extraction and productivity levels per unit area for most non-timber forest products are unknown, nor do we have much information about value addition at various points in the marketing channels. Here we determine extraction and productivity levels for Amla trees (Phyllanthus emblica), which yield fruits that are used for a wide variety of purposes in preparation of various foods, beverages and medicines. We also present preliminary data on the price appreciation of the fruit for one of the processed products. We have determined that the current level of extraction, 60-80% of all fruits at the population level, may have a negative effect on new recruitment. We present a model for value addition that has the potential to enhance income and reduce the level of extraction. This model is currently being implemented by the Soliga community with the assistance of a non-governmental organization.

The possible causes of low seed set in Syzygium cuminii, a woody tree bearing flowers with many ovules but fruits with single seeds, have been investigated. Pollen grain limitation and lack of fertilization do not completely explain the single seededness of fruits indicating the involvement of postfertilization factors. Developing ovules exhibited a clear pattern during the early fruit growth, and only one of the ovules eventually matured into a seed. Aqueous extracts of developing ovules significantly increased the rate of abortion of the other ovules in vitro, but the extent of abortion caused by aqueous extracts of maternal tissues from fertilized flowers did not differ from the control, implying that the developing ovules may produce a factor that causes the abortion of other ovules. Silver thiosulfate, an ethyleneaction inhibitor, significantly reduces the rate of such developing-ovule-mediated abortion in vitro as well as in vivo This study indicates that abortion in S. cuminii is mediated by chemic...

The evolution of endosperm, the tissue that nourishes developing embryos, has remained an enigma owing to its unique genetic composition. Because it contains both maternal (generally 2 doses) and paternal (1 dose) genomes, it is suggested to have evolved as a compromising tissue between the evolutionary interests of the maternal parent and offspring over resource allocation. This argument implies that in species where endosperm is highly functional and persistent, it quenches competition among developing embryos for resources and facilitates an equitable resource allocation to the developing offspring. Based on this argument we predict the association of well developed endosperm with certain features of fruits such as high ovule number per ovary and low extent of seed abortion. In this paper, we provide evidence in support of these predictions by analysing the data from 1131 species from the Flora of Presidency of Madras. We show that persistent and functional endosperm is more frequent in multiovulated than in uniovulated species and in species with less seed abortion. Our results also suggest that species with well developed endosperm tend to have uni-carpelled ovaries. Our analyses show that these associations are less likely to be emerging due to phylogenetic constraints. We argue that the endosperm has evolved as a maternal strategy of quenching the extent of sibling rivalry.

Differential development of seeds and their abortion in multi-ovulated fruits is explained by a process of self-organized movement of resource units into the developing ovules. This process involves movement of resource units would be autocatalytically favored and hence dominate over others at a rate defined by the sink-drawing ability of the ovules of a species. Such a process leads to varying levels of seed abortion that are independent of resource or pollen limitation and also predicts a positive relationship between the sink-drawing ability of a species and the extent of seed abortion in its fruits. We tested this prediction by (1) manipulating the sink-drawing ability of ovules in phaseolus vulgaris Linn., Vigna unguiculata Walp., Crotolaria medicaginea Lam., and Solanum seaforthianum Andr.; (2) analyzing the relationship between the in vivo sink-drawing ability and seed abortion in 15 species; and (3) using data from the literature. Our results seem to indicate that, as sink-drawing ability of ovule...

Measurement of total leaf area per plant in crop improvement programmes for a variety of purposes is often very tedious and time consuming. In this paper, we offer a rapid and non-destructive method of estimating the total leaf area in sunflower at the time of anthesis. We show that multiplying the leaf area of a specific leaf position from the apex by the total number of leaves per plant yields total leaf area with more than 95 % accuracy. The specific leaf position for any given genotype in sunflower can be arrived at by multiplying the total number of leaves per plant by the factor 0.355 and rounding off to the nearest highest integer. This technique can be used for the rapid estimation of leaf area per plant at anthesis for any given genotype of sunflower.

Differential development of sinks that depend on a common resource pool has been viewed as a consequence of an autocatalytic feedback process of flow of resource units into them. The feed-back process implies that the stronger a sink is relative to its competitors, the greater is its probability of getting further resources as a non-linear function of its resource drawing ability and sink size. We show that this model contrasts with that of the sink-strength dependent model in its prediction of the subsequent development of the initial asymmetry of growing leaves when their resource drawing ability is enhanced. By artificially enhancing the resource drawing ability of the leaves of Mestha (Hibiscus cannabinus L.) by external application of growth regulators, we test these predictions and show that the results are in conformity with the autocatalytic model proposed by Ganeshaiah and Uma Shaanker.

Fruit and seed abortion in plants have been traditionally attributed to limiting factors such as resources or to chemically mediated dominance hierarchy among the developing sinks. These hypotheses however do not satisfactorily explain the observed patterns of seed and fruit abortion and have also not withstood the test of critical experimentation. In this paper, we propose an alternative model based on the process of self organization used in physics to explain the flow of liquids etc. As proposed here, the model assumes one simple rule, that the probability of any given sink getting a resource molecule is a function of (a) the sink-drawing ability of each unit of the tissue and (b) the amount of resource molecules already moved to that sink. Accordingly, any resource molecule moving to a sink, autocatalytically increases the probability of the latter getting further resources. We show that starting from a set of identical sinks, all with equal sink-drawing ability, the differential development of sinks and thence their abortion might occur purely as a consequence of the autocatalytic or feedback movement of the resource molecules to the developing sinks. We also show that, such a process can lead to abortion even under resource-abundant conditions, though resource limitation aggravates the extent of abortion. Further, the extent of abortion is shown to be highly dependent on the sink-drawing ability of the species. We offer the test of this prediction in two ways: (a) in Derris indica the extent of abortion increases with the sink drawing ability of the fertilized ovules and (b) treatments involving growth regulators that increase the sink-drawing ability result in increased abortion of seeds and fruits. Based on these, we argue that self organization could be the basic process regulating resource flow to sinks and factors such as resource limitation and chemical inhibition might be additionally aggravating the asymmetry among the developing sinks.

Camptothecin and 10-hydroxycamptothecin are two important precursors for the synthesis of the clinically useful anticancer drugs, topotecan and irinotecan. In recent years, efforts have been made to identify novel plant and endophytic fungal sources of camptothecin and 10-hydroxycamptothecin. In this study we have isolated endophytic fungi strains from Apodytes dimidiata (Icacinaceae), a medium sized tree from the Western Ghats, India. The fungi were identified as Fusarium solani using both ITS rDNA sequencing and spore morphology. Two strains, MTCC 9667 and MTCC 9668 were isolated, both of which produced camptothecin and 9-methoxycamptothecin in their mycelia; one of the strains, MTCC 9668 also produced 10-hydroxycamptothecin, though in small amounts. The yields of camptothecin in MTCC 9667 and MTCC 9668 were 37 and 53 microg/100g, respectively, after 4 days of incubation in broth culture. The yields of 10-hydroxycamptothecin and 9-methoxycamptothecin in MTCC 9668 were 8.2 and 44.9 microg/100g, respectively. Further research in optimizing the culture conditions of these fungal strains might permit their application for the production of camptothecin and 10-hydroxycamptothecin.

SUMMARY The ratio of male to female flowers (sex ratio) in the monoecious Croton bonplandianum Baill decreased as plants aged in three habitats. Two major forces, male and female gametic success and intra-sexual selection, have been invoked to explain the decrease in sex ratio. While increasing female gametic success at successive stages of growth might be responsible for the enhanced allocation of resource to the females and hence for the absolute increase in number of female flowers at a later age, increasing male gametic success does not change the absolute number of male flowers but merely causes an increase in the number of pollen grains deposited on the stigma. Differences in the sex ratio between habitats was influenced by the differential fitness gained by the two sexes in the various habitats.

The paper traces shifts in the reproductive behaviour as influenced by the selective pressures of crop domestication, in the genus Eleusine, from the wild species. E. africana to its domesticated form E. coracana. Among other changes we consider temporal features of flowering, nature of anthesis and dehiscence, the stigma to lemma length ratio determining the extent of stigma protrusion and the pollen grain to ovule ratio as important in changing the breeding behaviours. These changes are viewed as evolutionary responses of plants to their respective ecological niches.

Impact of extraction of non-timber forest products (NTFPs) was analyzed in a thorn scrub forest in Biligiri Rangaswamy Temple (BRT) wildlife sanctuary, India. Six species are most commonly extracted from BRT scrub for subsistence and income generation by an aboriginal tribe, the Soliga. Although the forest has been provided protection from indiscriminate felling since 1978 under a wildlife sanctuary cover, changes in vegetation structure are still occurring as a consequence of anthropogenic pressure in the form of extraction of fuelwood and other NTFPs. The results indicate that large woody species are being replaced by small woody species. The population structure also is becoming increasingly skewed to the smaller size classes due to extraction-bound mortality of the individuals, particularly those>7 cm dbh and above. The data suggest that the scrub community itself may be a manifestation of long persisting anthropogenic pressure in the form of extraction of a variety of forest products, and it currently represents a downward transition from a deciduous forest to a shrub thicket.

The Andaman and Nicobar Islands, located in the Andaman Sea between peninsular India and Indo-Malaya, are part of two of the 34 mega-diversity hotspots of the world. These islands are characterized by their unique vegetation types such as littoral, mangroves, wet and semi-evergreen forests, and rainforests and for being the home for six aboriginal tribes of Negrito and Mongoloid descent. The islands are also home to a number of migrants and “settlers” from the Indian mainland and Myanmar. The aboriginal tribes and the settlers have a long history of association with the island’s bioresources. In this paper, we survey the ethnic uses of rattans, the unique climbing palms, about 63% of which are endemic to these islands. Our ethnobotanical survey revealed several uses of rattans by the Nicobarese and Shompens, the two major ethnic communities of the Nicobar Islands. In this study, besides the ethnic uses, we also estimated the revenue generated among those involved in the rattan trade (collectors, processors, and exporters).

We examined the response of forest tree species with different dispersal modes to anthropogenic pressure in a dry deciduous forest of South India. The species and their populations were sampled in two forest stands, one in proximity to a Soliga settlement (greater disturbance) and the other distant to the settlement (lower disturbance). Our results suggest that the populations of animal dispersed species than those of wind or passively dispersed species are more vulnerable to human disturbance. In fact wind dispersed species seem to be facilitated by human disturbances. The proximal site had a higher representation of understory plants and seedling belonging to wind dispersed species than that of animal dispersed species. We discuss the results in the context of the role of dispersal mode in shaping species response, and vegetation composition of forest to anthropogenic pressures.