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Pollination biology, breeding system and reproductive success of Adhatoda vasica,an important medicinal plant
Get PDFAdhatoda vasica Nees.(Acanthaceae) is an important
and widely used medicinal plant. The flowers last for
3–5 days, they are protandrous and pass through three
distinct phases: male, bisexual and female. Two species
of carpenter bees, Xylocopa verticalis and Xylocopa sp. are the effective pollinators. Pollen grains are deposited on the dorsal surface of the thorax during
Xylocopa visit to the flowers in the male phase, and the
stigma rubs the pollen-coated thorax and is pollinated
when the bees visit the flowers in bisexual and female
phases. There is a high level of geitonogamy. Pollination
efficiency under field conditions is high (95%). However,
fruit set is poor (6%). The species is self-incompatible.
None of the self-pollinated flowers sets fruits, but over
50% of the cross-pollinated flowers sets fruits. The results indicate that protandry does not prevent self pollination, but reduces interference in export and
import of pollen. Although the flowers have adapted
well to achieve a high level of pollination, reproductive
success in terms of fruit set is low, largely due to
the limitation of compatible pollen
Development of polymorphic microsatellite loci in Nothapodytes nimmoniana, a medicinally important tree from the Western Ghats, India.
No full textNothapodytes nimmoniana is a medicinally important tree species that occur in the Western Ghats, a megadiversity hotspot in southern India. Inner stem bark of the tree contains an important anti-cancer alkaloid, camptothecin for which the natural population of the tree is heavily harvested. In this paper, we report the isolation and characterization of eight polymorphic microsatellite loci using enrichment hybridization protocol. Analysis of 36 individuals representing two populations revealed three to 12 alleles per locus. Observed heterozygosity ranged from 0.21 to 0.94 for the two populations. None of the loci tested showed linkage disequilibrium. These markers are invaluable for evaluating the genetic structure and assessing the genetic impacts of harvesting of N. nimmoniana in the Western Ghats to formulate strategies for conservation of the species
Development of micro satellite markers for a critically endangered species, Ceropegia fantastica from the Western Ghats, India
No full textCeropegia fantastica L. (Asclepiadaceae) is a highly endemic and endangered species in the Western Ghats of India. Fourteen microsatellite markers were developed for C. fantastica. Eight microsatellite primers screened had 2–5 alleles per locus and the observed and expected heterozygosity ranged from 0.48 to 0.83 and 0.48 to 0.62, respectively. The primers were also evaluated for their cross amplification against two related species Ceropegia
hirsuta and Ceropegia oculata. The microsatellites
developed for this species could be used for addressing
population genetics of this endemic and critically endangered
species
The Cutting Edge of Conservation
Get PDFMention the word ‘conservation’ and for most people the mental images evoked are of tigers,elephants, giant pandas, marine turtles, or of imposing liana-festooned tropical rain forests. But conservation is as much about these iconic creatures and habitats as it is about other, less photogenic things: the tribal forest-dweller who depends on wild fruits for her livelihood and subsistence; the hill farmer deciding between growing an organic apple orchard or selling his land to a developer
wanting to build a mountain-view resort; the decision-makers sitting in far-off cities amending the wildlife protection act, or formulating policies about land use
Death sentence on taxonomy in India
Get PDFThe Biological Diversity Act, 2002 seriously curtails the scientific freedom of individual taxonomists by putting draconian regulations on the free exchange of specimens for taxonomic research and threatens to strangulate biodiversity research in India with legal as well as bureaucratic control 1. Rules and guidelines framed to implement the Biological Diversity Act, which itself is flawed and based on wrong premises, reveal the
appalling ignorance on the part of the implementing agencies. Guidelines accepted by the Ministry of Environment and Forests, Government of India and the
National Biodiversity Authority for international collaboration in biodiversity research are testimony to this. Draft guidelines accepted by the National Biodiversity Authority stipulate that ‘Exchange
and transfer of dead specimens and/or herbariums (of no commercial value) on loan for taxonomic studies and return by bona fide scientists/professors of recognized universities and Government Institutions of India who are engaged in pure classical taxonomic studies shall be done through the concerned departments/Ministries of the Government of India 2.’ Similarly, a recent notification
of the Ministry of Environment and Forests,based on the above guidelines,states that ‘In case the collaborative research projects involve exchange and transfer of dead or preserved specimen(s) and/or herbarium(s) of India on loan or on any other terms for taxonomic studies as required by bona fide scientists/ professors of recognized universities and Government Institutions of India who are engaged in pure classical taxonomic studies, this shall be done with the approval of concerned Departments/Ministries of the Government of India3.’ These guidelines on implementation would achieve the ultimate bureaucratic control in the history of science in India! Proponents of these guidelines have already revealed their mettle through some ludicrous
suggestions to entomologists to send pictures, not (dead) specimens, for identification 4. Being paranoid about
biopiracy(!), they may even suggest that microbiologists send digital images of microbes abroad for identification, as live cultures are required for identification and they can be easily multiplied
and patented
Are plants with anti-cancer activity resistant to crown gall?: a test of hypothesis
Get PDFThe Crown gall tumour assay (CGTA) is one of several bench top bioassays recommended for the rapid screening of plants with anti-cancer activity. The rationale for the use of the bioassay is that the tumorogenic mechanism initiated in plant tissues by Agrobacterium tumefaciens is in many ways similar to that of animals. Several plant species with anti-cancer activity have already been discovered using this bioassay. However till date no explicit test of an association between anti-cancer activity of plants and their resistance to crown gall formation has been demonstrated. Demonstration of an association could have exploratory potential when searching for plants with anti-cancer activity. In this paper, we determined whether or not a statistically significant association between crown gall resistance and anti-cancer activity exists in plants found in existing published data sets. Our results indicate that plants with anti-cancer activity have a higher proportion of their species resistant to crown gall formation compared to a random selection of plants. We discuss the implications of our results especially when prospecting for newer sources of anti-cancer activity in plants
Response of ants to disturbance gradients in and around Bangalore,India
No full textThere is an emphasis the world over to build back biodiversity even in humandominated landscapes, such as cityscapes. Birds and butterflies that are highly vagile have been studied extensively, but less mobile taxa such as ants have been ignored, for this reason we chose them as the study taxa for this work. The distribution and abundance of ant species across a disturbance gradient in and around Bangalore city was studied. Five sites were
sampled and these represented a gradient of urban land use that ranged from highly disturbed to comparatively less disturbed areas. A total of 51 species of ants belonging to seven subfamilies were recorded. Ant species richness and abundance was higher in the disturbed
site. Species richness is significantly correlated with litter and canopy cover. Common species increased with disturbance. Disturbed sites supported rare species, suggesting that these habitats located in urban settings also require protection. The management implications of the results are discussed
Habitat factors affecting site occupancy and relative abundance of four-horned antelope
No full textThe four-horned antelope is endemic to the Indian sub-continent. It was formerly distributed widely in deciduous forests throughout its range, but the current
distributional patterns of this low-density species are largely unknown and conservation efforts are hampered by the lack of information on species–habitat relationships. We investigated the habitat factors influencing four-horned antelope occurrence and abundance in Bandipur National Park, an important four-horned antelope conservation site in India. Detection/non-detection data, collected under a systematic sampling framework, were used to test a priori hypotheses incorporating covariates believed to influence occurrence and abundance. The best fitting models for four-horned antelope occurrence and relative abundance reveal that the tree-savanna deciduous habitat sub-type, characterized by relatively open habitats with a lower tree density and a high degree of deciduousness, is most preferred by the species. Four-horned antelope conservation efforts in Bandipur National Park and other reserves should be focused on areas typified by treesavanna habitats. Four-horned antelope occurrence was negatively related to the alien weed Lantana camara. The prolific spread of this weed in Indian deciduous forests is a likely threat
The Economic Impact of Forest Hydrological Services on Local Communities: A Case Study from the Western Ghats of India
Get PDFThe conventional wisdom that 'more forest is always better' has dominated policy making in the management of forested watersheds. In the context of the supposed hydrological regulation service provided by forest ecosystems, however, hydrologists have debated this assumption for more than two decades. Unfortunately, detailed studies of the relationship between forest cover, hydrology and the economic use of water have been relatively scarce, especially in the tropical forests of South Asia. Building upon a larger research project at four sites in the Western Ghats of peninsular India, this study examines the link between stream flow, agricultural water use an economic returns to agriculture. The study attempts to simulate the likely impacts of regeneration of a degraded forest catchment on stream flow and the consequent impact on irrigation tank based agriculture in a downstream village. The authors find that regeneration of forests would reduce the ratio of runoff to rainfall in the forested catchment thereby significantly reducing the probability of filling the well-used irrigation tank. This in turn reduces the probability of the command area farmers being able to cultivate an irrigated paddy crop, particularly in the summer season, thereby reducing expected farm income as well as wage income for landless and marginal landowning households. The study results seem counter intuitive to conventional wisdom. This result is, however, not because the hydrological relationships in this region are peculiar, but because the community immediately downstream of the forest is using water in a particular manner, viz., through irrigation tanks for growing water-intensive crops. The main implication is that policymakers must move away from simplistic notions of forests being good for everything and under all circumstances, and facilitate context-specific, ecologically and economically informed forest governance
Adult butterfly communities in coffee plantations around a protected area in the Western Ghats, India
No full textAlthough large areas of relatively undisturbed forests are essential for preserving biodiversity, opportunities for conservation in human-dominated landscapes must
not be overlooked. Agroforestry systems such as shaded coffee plantations are known to be more compatible with biodiversity conservation than other, more drastic, land transformations. In recent times, however, modernization of coffee cultivation has influenced its conservation values adversely. We evaluated adult butterfly diversity in 12 coffee plantations around a protected area (PA) in the Western Ghats, India. We sampled 25 transects that varied in distance from the PA and in proportion of silver oak Grevillea robusta, an exotic timber species. We also had two transects within the PA. We used a combination of line transects and fruit bait traps to sample butterflies. Micro-climatic variables (temperature, humidity and light intensity) and other habitat variables (e.g. canopy cover, tree diversity,
herb species richness) were recorded for each transect. We analyzed the effect of these variables on the abundance and species richness of butterflies, overall as well as in different families, feeding guilds and size classes. Proximity to the PA significantly influenced the abundance and richness of butterflies in coffee plantations, with transects close to the PA having higher abundance and richness than transects further away. Also, in terms of butterfly species composition, similarity
to forest declined with increasing distance. Among the habitat variables, only canopy cover had a significant effect on abundance and richness, and the effect was
negative. These patterns, with some exceptions, were also reflected for different families and feeding guilds. The proportion of silver oak had no apparent effect on butterflies. This study demonstrates that coffee plantations can act as a buffer for butterfly fauna within a certain radius of a PA. They have great potential as auxiliary tools and can significantly complement conservation efforts that are currently centered on PAs