Population structure of Spanish mackerel Scomberomorus commerson (Lacepede 1800) in the Northern Indian Ocean determined using microatellite markers

Narrow barred Spanish mackerel, Scomberomorus commerson (Lacepede, 1800) is one of the economically important marine fish species in the Northern Indian Ocean. Genetic stock structuring is reported in S. commerson from Arabian Peninsula, Indo-West Pacific, Northern Australian, Southeast Asia and Northern Australia. The present study utilized microsatellite markers to elucidate the population structure of S. commerson (Lacepede, 1800) in the Arabian Sea and Bay of Bengal. A total of 12 polymorphic microsatellite loci were amplified in 250 samples collected from five different geographic locations. Low FST values (0.0023–0.027), AMOVA, PCoA and the Bayesian analysis of genetic structure indicated unit stock of the species in Indian waters. Bottleneck analysis using Wilcoxon signed rank tests and Mode shift test indicated lack of recent bottleneck events across populations of S. commerson. The findings of the present study could be used in managing the commercially important species, S. commerson as a unit stock in Arabian Sea and Bay of Bengal of Northern Indian Ocean and reinforces the need for regional cooperation on fisheries management

Identification and characterisation of microsatellite markers in narrow barred Spanish mackerel Scomberomorous commerson (Lacepede, 1800)

Narrow barred Spanish mackerel, Scomberomorus commerson (Lacepede 1800) is one of the commercially important fish in Indian waters. For sustainable management of the species, it is necessary to understand the genetic stock structure of the species. Accurate delineation of genetic stock structure can be achieved using nuclear microsatellite markers. A study was carried out to identify and validate polymorphic microsatellite markers in S. commerson using information available from closely related fish species. The study could identify 10 polymorphic microsatellite loci which can be effectively utilised for identifying genetic stock structure of the species. Validation of the identified loci was also done by testing the loci in natural populations of the species. The findings of the present study will be useful in devising stock-specific management measures for conservation and sustainable utilisation of this commercially important fish species in Indian waters

Guild structure, diversity and succession of dung beetles associated with Indian elephant dung in South Western Ghats forests

The diversity, guild structure and succession of dung beetles associated with Indian elephant dung is described in a deciduous forest site in Western Ghats, a hot spot of diversity in India. Dung beetles were collected using baited pitfall traps and from exposed dung pats in the forest at intervals of 1, 3, 5, 7, 15 and 21 days. Twenty-one dung beetle species belonging to the 3 major functional guilds were recorded. Abundance of dwellers was high compared to rollers deviating from earlier reports on the high abundance of rollers in the afrotropical regions. Dweller Drepanocerus setosus and tunneler Onthophagus bronzeus were the most abundant species. Dung pats aged 3–5 days attracted the highest abundance of dung beetles. Bray Curtis similarity index indicated low community similarity between different stages of succession. Species richness and abundance of tunnelers increased with dung age and decreasing moisture up to a threshold level, followed by a decrease. Rollers and dwellers did not show any significant relationship with dung moisture content. Further research is needed to estimate the dung beetle community associated with the dung pats of other mega herbivores as well as of elephant dung in other forests of the Western Ghats

<b>Effect of <i>N⁶</i>-Benzyl amino purine and Naphthalene acetic acid on camptothecin production through <i>in vitro</i> propagation of </b> <b><i>Ophiorrhiza</i></b><b><i> rugosa </i>Wall.</b><b> var.<i> decumbens</i> (Gardn. ex Thw.) Deb & Mondal </b> <b> </b>

405-409In vitro production of camptothecin (CPT) was achieved by the establishment of multiple shoot and root cultures of Ophiorrhiza rugosa Wall. var. decumbens (Gardn. ex Thw.) Deb & Mondal. The maximum multiple shoots were obtained in Murashige and Skoog (MS) medium supplemented with 5mg/l N6-benzyl amino purine (BA) along with 0.5mg/l naphthalene acetic acid (NAA). Optimal root generation was observed in Murashige and Skoog medium with 2mg/l NAA and 0.05mg/l BA. However, CPT content found to be elevated in shoot and root cultures where growth hormones imposed growth inhibition. The maximum amount of CPT in multiple shoots was 0.039% while shoots of plant grown in the field showed 0.002 per cent. In root cultures, CPT content was 0.065% whereas roots of intact plant showed only 0.024 per cent

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Not AvailableThe DNA “barcode”, the partial sequence of the mitochondrial gene cytochrome C oxidase subunit I (COI), was assessed for species identification within the genus Macolor. The Midnight Snapper, Macolor macularis Fowler 1931, is compared with its only congener, the Black and White Snapper, Macolor niger (Forsskål 1775), both collected from the south-west coast of India. The examination of fresh specimens of the two species showed diagnostic anatomical and coloration differences and the DNA barcoding showed a genetic divergence of 3.51% between the species. We provide a description and illustrations of DNA-barcoded specimens, assess the reliability of some key marking characters for the two species, and document the DNA barcodes for Indian specimens.Central Marine Living Resources and Ecology (CMLRE) and The Ministry of Earth Sciences (MoES), Government of India

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Not AvailableIn the present study three species of mackerel, Rastrelliger present in Indian waters were taken for genetic identification using cytochrome c oxidase subunit I and 16s rRNA sequences. Accurate identification of these species is important for fishery management as its morphological characters are very similar. In this study, the sequences of COI and 16S rRNA were determined from 19 individuals of three Rastrelliger species, Rastrelliger kanagurta, Rastrelliger brachysoma and Rastrelliger faughni from Andamans and Indian mainland to study the phylogenetic relationship. The intraspecies and interspecies genetic distance ranged from 0.000 to 0.002 and 0.007 to 0.015 respectively based on 16S rRNA sequences. Using COI data analysis, the intraspecies genetic distance ranged from 0.000 to 0.012, while it varied from 0.039 to 0.086 for interspecies. The present study clearly demarcates three species of mackerel based on the mitochondrial genetic sequences and also showed a non-descriptive genetic distance of R. kanagurta from mainland and Andaman Islands.Central Marine Living Resources and Ecology (CMLRE)The Ministry of Earth Sciences (MoES), Government of IndiaBOBLME/FA

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Not AvailableScomberomorus commerson is an economically important migratory fish distributed worldwide. The genetic stock structure of S. commerson distributed along the Indian waters was identified using mitochondrial ATPase 6 and 8 genes. A total of 842 bp sequence of ATPase 6/8 genes obtained in this study revealed 23 haplotypes with mean low nucleotide diversity and high haplotype diversity. Co-efficient of genetic differentiation (FST) values obtained for pair wise populations were low and non-significant with an overall value of -0.02074. The high haplotype and low nucleotide diversity values together with mismatch distribution analysis suggested a history of genetic bottleneck events or founder effect, with subsequent population expansion in S. commerson. The findings of the present study indicated the panmixia nature of the species which can be managed as a unit stock in Indian waters.Not Availabl

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Not AvailablePopulation genetic structure of the pelagic narrowbarred Spanish mackerel (Scomberomorus commerson) was examined in 10 populations from the Indo-West Pacific region, based on mitochondrial control region DNA.We examined genetic composition of 56 individuals of S. commerson from the Arabian Sea, Bay of Bengal, and compared them with 40 individuals from previously published data sampled from the ROPME Seas area and South West Pacific Ocean. The overall nucleotide and haplotype diversities were estimated to be 0.072 and 0.995, respectively. Demographic parameters such as Tajima’s D and Fu’s Fs statistics were negative, but non-significant across all the populations, except for New Caledonia in the South West Pacific, indicating a stable population of S. commerson in this region. To assess intra-specific patterns of connectivity, we constructed statistical parsimony networks among haplotypes and estimated time of most recent population expansion.AMOVA and FST values among Indian and Arabian regions revealed non-significant variation among the populations, while separation was noted among the samples of the northern and eastern Indian oceans, as well as with South West Pacific. A parsimony network analysis provided evidence for four separate population segment/stocks in the Indian Ocean and Pacific Ocean, raising a conservation concern. Our results support a need for regional cooperation to ensure the sustainable exploitation of S. commerson in the Indo-West Pacific region.Not Availabl

Hints for panmixia in Scomberomorus commerson in Indian waters revealed by mitochondrial ATPase 6 and 8 genes

Scomberomorus commerson is an economically important migratory fish distributed worldwide. The genetic stock structure of S. commerson distributed along the Indian waters was identified using mitochondrial ATPase 6 and 8 genes. A total of 842 bp sequence of ATPase 6/8 genes obtained in this study revealed 23 haplotypes with mean low nucleotide diversity and high haplotype diversity. Co-efficient of genetic differentiation (FST) values obtained for pair wise populations were low and non-significant with an overall value of −0.02074. The high haplotype and low nucleotide diversity values together with mismatch distribution analysis suggested a history of genetic bottleneck events or founder effect, with subsequent population expansion in S. commerson. The findings of the present study indicated the panmixia nature of the species which can be managed as a unit stock in Indian waters

Four evolutionarily significant units among narrow-barred Spanish mackerel (Scomberomorus commerson) in the Indo-West Pacific region

Population genetic structure of the pelagic narrowbarred Spanish mackerel (Scomberomorus commerson) was examined in 10 populations from the Indo-West Pacific region, based on mitochondrial control region DNA.We examined genetic composition of 56 individuals of S. commerson from the Arabian Sea, Bay of Bengal, and compared them with 40 individuals from previously published data sampled from the ROPME Seas area and South West Pacific Ocean. The overall nucleotide and haplotype diversities were estimated to be 0.072 and 0.995, respectively. Demographic parameters such as Tajima’s D and Fu’s Fs statistics were negative, but non-significant across all the populations, except for New Caledonia in the South West Pacific, indicating a stable population of S. commerson in this region. To assess intra-specific patterns of connectivity, we constructed statistical parsimony networks among haplotypes and estimated time of most recent population expansion.AMOVA and FST values among Indian and Arabian regions revealed non-significant variation among the populations, while separation was noted among the samples of the northern and eastern Indian oceans, as well as with South West Pacific. A parsimony network analysis provided evidence for four separate population segment/stocks in the Indian Ocean and Pacific Ocean, raising a conservation concern. Our results support a need for regional cooperation to ensure the sustainable exploitation of S. commerson in the Indo-West Pacific region