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Diversity, biomass and carbon (C) stock (above- and below-ground) of woody species (≥5 cm dbh) were studied in 15 Community Reserves (CRs) of Meghalaya, Northeast India. A total of 287 species belonging to 72 families and 165 genera were enumerated from 7.5 ha sampled area. The number of individuals ranged from 888 to 1582 ha-1 with a mean density of 1182.4±57.76 individuals ha-1. The basal area ranged from 22.27 to 59.22 m² ha-1 with a mean value of 41.60±3.23 m² ha-1 in the studied sites. The total biomass and C stock ranged from 147.57 to 343.25 Mg ha-1 and 69.95 to 162.7 Mg C ha-1, respectively. The contribution of AGB and BGB to the total biomass and C stock was 79-82% and 18-21%, respectively. The variation in species richness, density, basal area, biomass, and carbon stock observed in the studied CRs can be attributed to their past land use and management history. The present study highlights that these CRs possess a high potential to act as carbon sinks, indicating that creating more CRs in the state could prove highly beneficial. Such an approach would not only help to preserve the region's rich biodiversity but also aid in sequester the atmospheric carbon dioxide. [ABSTRACT FROM AUTHOR]

Ilex embelioides Hook.f. is a threatened tree species endemic to northeastern India. The species propagates naturally through seeds but shows a brief dormancy period. The present study was carried out to assess the germination behaviour, and identify the suitable storage conditions of I. embelioides seeds. Results revealed that warm stratification for 30 days could effectively break dormancy. Seeds pre-treated with gibberellic acid (GA3, 2,000 mg L-1) showed highest germination (63.89 ± 0.91%) as compared to other concentrations of GA3 as well as potassium nitrate (KNO3). Highest in vitro seed germination percentage (65.56 ± 2.92%) was recorded on (Murashige and Skoog) MS medium containing 10 mg L-1 GA3. The viability of the seeds declined with storage period irrespective of its storage condition. After 30 days, highest viability (54.72 %) was observed in seeds stored in moist sand at 25°C. Therefore, application of GA3 and warm stratification (25 ± 1°C) along with a substrate (moist sand) for 30 days may be considered as ideal conditions for effective germination and storage of I. embelioides seeds. This study can also be used for mass propagation of the species for reintroduction in the wild. [ABSTRACT FROM AUTHOR]

The present study was carried out to investigate the orchid diversity in community managed subtropical broad-leaved forests in Khasi Hills of Meghalaya. A total of 87 community forests were surveyed in Khasi Hills. The study revealed the presence of 123 species belonging to 54 genera. The highest numbers of species (66) were recorded in sacred forests, followed by reserved (51) and village (32) forests. Majority of the recorded species (87) were epiphytic and 36 were terrestrial. Of all the species, 28 (22.76%) were recorded as endemic and 12 (9.76%) were rare. Dendrobium with 19 species was the dominant genera followed by Coelogyne with 11 species. Owing to a number of anthropogenic disturbances followed by habitat loss, these species are subjected to continuous threat, hence warrants immediate conservation actions. Therefore, it is suggested that mass propagation, through conventional and tissue culture techniques should be adopted to conserve the dwindling orchid diversity of the state. [ABSTRACT FROM AUTHOR]

Asymbiotic seed germination has revolutionised the commercial production of exotic orchids as well as conservation of rare and endemic ones. However, the success of the process largely depends on the sterilisation procedure adopted to disinfect the minute dust like orchid seeds. The present study incorporates the technique of centrifugation method to successfully disinfect the exposed seeds obtained from the dehisced capsule of Phaius tankervilleae, which is an ornamental orchid endemic to Northeast India. The seeds of P. tankervilleae showed 100% disinfection as well as germination efficiency (with 5% NaOCl and 8 mins exposure) with no risk of physical damage to the seeds due to the centrifugation process (4 mins at 4000 rpm under 4°C). Inoculated seeds showed the first sign of swollen embryos (PLBs) after 5 weeks of culture in Murashige and Skoog (1962) (MS) medium. PLBs obtained were subcultured on MS medium supplemented with different plant growth regulators for healthy proliferation and shoot multiplication. MS medium supplemented with 2 mg/L each of BAP and KN resulted in best overall shoot and root development. Therefore, the present study reports a simple yet effective sterilisation procedure to disinfect exposed P. tankervilleae seeds which is quick, easy and very efficient for mass scale propagation as well as ex-situ conservation of this valuable orchid species and other orchid species as well. [ABSTRACT FROM AUTHOR]

Objective: This study investigates the potential estrogenic activity of the ethanolic extract of Flemingia vestita Benth tubers using ovariectomized rat model. Materials and Methods: The ethanolic extract of F. vestita tubers has been standardized using validated HPLC method in terms of its genistein content (8.43 ± 0.05 mg/g of extract). Three to four week old young albino Wistar female rats were ovariectomized and treated for 14 days post ovariectomy with the standardized ethanolic extract at three different dose levels (100, 250, 500 mg/kg body weight) with a positive control of Estradiol valerate (1 mg/kg/day). The parameters evaluated were uterine weight, uterine glycogen, G6PDH, LDH, 17β-estradiol, progesterone, total cholesterol, triglycerides, HDL and histo architecture of uterus. Results: Treatment with the ethanolic extract of F. vestita tubers showed dose dependent increase in uterine weight, glycogen levels, G6PDH levels, estrogen and progesterone levels when compared with the ovariectomized control. Amongst three dose levels, high dose of plant extract showed significant increase in the uterine weight (p < 0.001), uterine glycogen content (p < 0.001), 17-β estradiol and progesterone levels (p < 0.001), G6PDH and LDH levels (p < 0.001) as well as significant decrease in HDL and triglycerides levels (p < 0.001) compared to ovariectomized control. Histopathological evaluation of uteri sections revealed that the high dose of the plant show increase in the endometrial response as indicated by proliferation of endometrial glands and luminal epithelium of the ovariectomized rats. Conclusion: Thus, these data suggests that ethanolic extract (500 mg/kg body weight) of F. vestita tubers may exhibit good estrogenic activity in ovariectomized rat model. [ABSTRACT FROM AUTHOR]