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A new ant species of the genus Anochetus (Hymenoptera: Formicidae) from India with a remarkable nest entrance architecture
Full text linkA new ant species, Anochetus daedalus, is described based on worker caste collected from a nest in secondary tropical semi-evergreen forest from Sirsi, Karnataka, India, part of the Western Ghats biodiversity hotspot. It is very similar to Anochetus nietneri Roger, but is distinctly different in shape of the petiole. The species is notable for constructing elaborate nest entrance which resembles ‘fort nests’ constructed by some Pheidole spp
Establishment and standardization of in vitro regeneration protocol in Nothapodytes nimmoniana Graham and evaluation of camptothecine (CPT) in tissue culture plants
No full textNothapodytes nimmoniana Graham is an important medicinal tree species occurring in the Western Ghats, a mega diversity hotspot in Southern India. The inner stem bark of the tree contains an important anticancer alkaloid, camptothecine (CTP), for which the natural population of the trees is heavily extracted. In this paper, we report the development of a rapid, high frequency regeneration protocol from leaf and nodal explants of N. nimmoniana. Multiple shoot induction was carried out using leaf and nodal explants on Murashige and Skoog (MS) medium supplemented with different concentration/ combination of phyto-hormones. N6-benzyladenine (BA) was the most effective cytokinin for the induction of multiple shoots. The MS medium with 8.87 lM BA yielded the highest number of shoots from leaf and nodal explants, respectively. Further, proliferation and elongation of adventitious buds were observed in secondary medium containing MS supplemented with 4.44 lM BA and 0.87 lM gibberellic acid (GA3). Shoots were rooted on half strength MS medium containing 4.9 lM indole-3-butyric acid. The plantlets were acclimatized in a growth chamber at 25 "C, 60 % relative humidity, with 16/8 h light/dark photoperiod. Regenerated plants were free of any noticeable phenotypic variability and showed a survival rate of 90 %. The in vitro regenerated plants accumulated substantial amount of camptothecine (ranging from 0.08 to 0.2 %). These results suggest the possibility of using in vitro regenerated plants as a possible alternative source
of CPT. This is the first report of direct regeneration in N. nimmoniana with significantly high plant regeneration frequency and with high CPT yiel
An Enquiry into Equity Impact of Groundwater Markets in the Context of Subsidised Energy Pricing: A Case Study
No full textIn India, groundwater over-extraction is often linked with subsidized electricity in the agricultural sector. Proponents of electricity subsidy argue that such a subsidy helped even the resource-poor farmers to have had access to groundwater irrigation. This article explores inter- and intra-generational equity implications of groundwater markets in the context of subsidized electricity where the market enables even non-well owners to access groundwater for irrigation. The study is
based on survey data collected from two districts in the state of Madhya Pradesh, India. The sample includes farmers who use electricity- and diesel-powered pumps to lift groundwater. The structure of the existing water market is examined through the determination of the water price–cost ratio. The article finds that, in the short run, water markets improve accessibility to groundwater irrigation, particularly for marginal and small farmers. With the help of this, farmers are able to mitigate water-scarcity-related vulnerabilities. However, in the long run, electricity subsidy may have negative dynamic
implications by causing over-exploitation of groundwater that reduces the volume of groundwater available for future agricultural use. In other words, this article finds that, in the initial phases of the development of the water markets, there are intra-generational equity implications. However, in the advanced phases, the unsustainable extraction of groundwater could lead to inter-generational inequities
Conservation of a fragmented population of blackbuck (Antilope cervicapra)
Full text linkThe Vallanadu Blackbuck Sanctuary (VBS), Tamil Nadu, India is a small protected area (PA) designated to conserve blackbuck. We did a study on habitat use and suitability in the PA that has come under various
management interventions. The occupancy of blackbuck
was positively correlated with areas lying within the PA, but the encounter rate of blackbuck was significantly
higher in areas outside the PA. Being small in size, VBS may not hold a large population of blackbucks, but may help in saving the species which once widely occurred in the southernmost parts of India
Turning turtle
Full text linkIn September this year, the Tamil Nadu Fisheries Department issued an order that banned all forms of fishing within a radius of 5 nautical miles (9.3 km) at 90 sites along the State’s coastline. It was passed to safeguard migrating olive ridley sea turtles. Extending from January to the end of April, the ban is applicable across eight coastal districts — from Chennai in the north to Kanyakumari in the south
DNA barcoding and NMR spectroscopy-based assessment of species adulteration in the raw herbal trade of Saraca asoca (Roxb.) Willd, an important medicinal plant
No full textSaraca asoca (Roxb.) Willd, commonly known as "Asoka" or "Ashoka" is one of the most important medicinal plants used in raw herbal trade in India. The bark extracts of
the tree are used in the treatment of leucorrhea and other uterine disorders besides also having anti-inflammatory, anti-bacterial, anti-pyretic, anti-helminthic, and analgesic activity. The indiscriminate and rampant extraction of the wood to meet the ever-increasing market demand has led to a sharp decline in
naturally occurring populations of the species in the country. Consequently, the species has recently been classified as Bvulnerable^ by the International Union for Conservation of Nature (IUCN). Increasing deforestation and increasing demand for this medicinal plant have resulted in a limited supply and suspected widespread adulteration of the species in the raw herbal trade market. Adulteration is a serious concern due to:
(i) reduction in the efficacy of this traditional medicine, (ii) considerable health risk to consumers, and (iii) fraudulent product substitution that impacts the economy for the Natural Health Product (NHP) Industry and consumers. In this paper, we provide the first attempt to assess the extent of adulteration in the raw herbal trade of S. asoca using DNA barcoding validated by NMR spectroscopic techniques. Analyzing market samples drawn from 25 shops, mostly from peninsular India, we show
that more than 80 % of the samples were spurious, representing plant material from at least 7 different families. This is the first comprehensive and large-scale study to demonstrate the widespread adulteration of market samples of S. asoca in India. These results pose grave implications for the use of raw herbal drugs, such as that of S. asoca, on consumer health and safety.
Based on these findings, we argue for a strong and robust regulatory framework to be put in place, which would ensure the quality of raw herbal trade products and reassure consumer confidence in indigenous medicinal systems
Transcriptome analysis of stem wood of Nothapodytes nimmoniana (Graham) Mabb. identifies genes associated with biosynthesis of camptothecin, an anti-carcinogenic molecule
Full text linkCamptothecin (CPT), a monoterpene indole alkaloid, is a potent inhibitor of DNA topoisomerase I and has applications in treating ovarian, small lung and refractory ovarian cancers. Stem wood tissue of Nothapodytes nimmoniana (Graham) Mabb. (family Icacinaceae) is one of the richest sources of CPT. Since there is no genomic or transcriptome data available for the species, the present work sequenced and analysed transcriptome of stem wood tissue on an Illumina platform. From a total of 77,55,978 reads, 9,187 transcripts were assembled with an average length of 255 bp. Functional annotation and categorization of these assembled transcripts unraveled the transcriptome
architecture and also a total of 13 genes associated with CPT biosynthetic pathway were identified in the stem wood
tissue. Four genes of the pathway were cloned to full length by RACE to validate the transcriptome data. Expression analysis of 13 genes associated with CPT biosynthetic pathway in 11 different tissues vis-à-vis CPT content analysis suggested an important role of NnPG10H, NnPSLS and NnPSTR genes in the biosynthesis of CPT. These results indicated that CPT might be synthesized in the leaves and then perhaps exported to stem wood tissue for storage
Integrative Taxonomic Approach for Describing a New Cryptic Species of Bush Frog (Raorchestes: Anura: Rhacophoridae) from the Western Ghats, India
Full text linkA new cryptic species of bush frog Raorchestes honnametti sp. nov. is described from the south-eastern part of the Western Ghats, India. This newly described species belongs to the Charius clade and is morphologically similar to other clade members—R. charius and R. griet. Therefore, an integrative taxonomic approach based on molecular and bioacoustic analysis along with morphology was used to delimit the new species. Raorchestes honnametti sp. nov., is currently known only from Biligiri Rangaswamy Temple Tiger Reserve, a part of Biligiri Rangaswamy horst mountain range (a mountain formed due movement of two faults) formed during the Late Quaternary period (1.8–2.58 Ma). Discovery of cryptic species from a highly speciose and well-studied genus Raorchestes hints at the possible existence of several more cryptic species in this genus. We discuss the possible reasons for crypsis and emphasize the need for continued systematic surveys of amphibians across the Western Ghats
Half-Earth or Whole Earth? Radical ideas for conservation, and their implications
No full textWe question whether the increasingly popular, radical idea of turning half the Earth into a network of protected areas is either feasible or just. We argue that this Half-Earth plan would have widespread negative consequences for human populations and would not meet its conservation objectives. It offers no agenda for managing biodiversity within a human half of Earth. We call instead for alternative radical action that is both more effective and more equitable, focused directly on the main drivers of biodiversity loss by shifting the global economy from its current foundation in growth while simultaneously redressing inequality
Fertilization in Flowering Plants 2. Selection of the Male Partner is the Prerogative of the Maternal Parent
Full text linkAfter the pollen grain reaches the stigma through outsourced
agents (pollinators), the next step before fertilization is to select the right type of pollen. Similar to a marriage in human beings, flowering plants also have evolved elaborate screening process to select the right pollen grains and to reject the wrong ones. Even after initial screening for the right pollen, the pistil imposes a tough competition amongst them, comparable to a swayamvara of Indian mythology, to select the best available pollen. Flowering plants have evolved into a matriarchal society. The selection of the male partner is totally the prerogative of the mother (pistil); the boy (pollen grain) and the girl (ovule) has no say in this selection