Nokrek Biosphere Reserve Research Articles

Checklist of the orchids of Nokrek Biosphere Reserve, Meghalaya, India

A study on the diversity and distribution of different orchid species in Nokrek Biosphere Reserve (NBR) was carried out from 2009 to 2015 with an objective to assess the threatened plants present in protected areas. A total of 127 species of orchids belonging to 56 genera were identified from NBR; out of which 94 are epiphytes or lithophytes, 32 are terrestrial, and one species is mycoheterotrophic. Dendrobium (21 spp.) is the most dominant genus in terms of the species composition, followed by Bulbophyllum (8 spp.), Coelogyne (8 spp.), Liparis (7 spp.), Cymbidium (5 spp.), and Pinalia (4 spp.). Other dominant genera include Aerides, Agrostophyllum, Cleisostoma, Habenaria, Micropera, Paphiopedilum, and Pholidota which were represented by three species each. A total of 10 genera were recorded that were represented by two species include Acampe, Cryptochilus, Dendrolirium, Gastrochilus, Oberonia, Peristylus, Phalaenopsis, Pleione, Spathoglottis, and Vanda. Of the recorded species from NBR, the Gastrochilus calceolaris is assessed by the IUCN Red List as ‘Critically Endangered’, Paphiopedilum insigne and P. venustum are ‘Endangered’, P. Hirsutissimum as ‘Vulnerable’, and Dendrobium aphyllum as ‘Least Concern’. It has been observed that at the higher elevations, subtropical and temperate forests provide a conducive environment for the orchids to occupy a pristine ecosystem because the temperature and maximum humidity recorded in those areas is lower in comparison to lower regions. This research finding recommends the designation of Nokrek hill as a permanent orchid sanctuary for germplasm collection and conservation, as it could better guarantee the survival of threatened plants and reduce human interventions in the forested zone.

Metabolic Diversity of Flavonoids and Antioxidant Potential for Characterization of Underutilized Citrus Species for Nutritional Security.

Citrus fruits are grown commercially throughout the world. They are widely consumed due to their nutrients, use in energy supplements, and numerous health benefits. There is significant interest among consumers about this naturally available source, rich in flavonoids and antioxidants. However, underutilized citrus varieties remain unexplored due to the lack of information about the pool of nutritive properties they confer. Ten underutilized citrus varieties were collected from Nokrek Biosphere Reserve, West Garo Hills, Meghalaya, India, identified by UNESCO as a Biosphere reserve, to study the diversity in terms of limonin, ascorbic acid, carotenoids, browning, flavonoids, total phenol, and antioxidant activity, the contents of which varied significantly among different citrus cultivars. The results indicated that Citron and Pomelo were good sources of ascorbic acid (29.50 and 45.09 mg/100 mL), and that Khasi papeda was found to contain lower limonin content (9.21 ppm). However, in terms of flavonoids, Khasi papeda and Pomelo were found to exhibit a higher naringin content (189.13 ppm and 32.15 ppm), whereas the hesperidin content was highest in Kachai lemon, Khasi papeda, and Chinotto, at 199.51 ppm, 148.04 ppm, and 135.88 ppm, respectively. Antioxidant activity was assessed by three antioxidant assays (ABTS+ (radical cation azino-bis [3-ethylbenzthiazoline-6-sulfonic acid]) (ABTS), 2,2-diphenyl-1-picrylhydrazyl radical (DPPH), and Ferric Reducing Antioxidant Power (FRAP)). Khasi papeda (7.48 mM L−1 Trolox), Chinotto (7.48 mM L−1 Trolox), and Pomelo (7.48 mM L−1 Trolox) exhibited the highest reducing power with DPPH radical scavenging activity, and Khasi papeda (15.41 mg GAE L−1) possessed a higher phenolic content, whereas the antioxidant activity when assessed with ABTS and FRAP assays was highest among the underutilized species of Khasi papeda (4.84 mM L−1 Trolox, 1.93 mM L−1 Trolox) and Ada Jamir (4.96 mM L−1 Trolox, 2.03 mM L−1 Trolox), respectively. To the best of our knowledge, this is among the very few papers presenting comprehensive data on the metabolic diversity of flavonoids and antioxidant potential to characterize the underutilized citrus species. This study also demonstrated that Khasi papeda, Pomelo, Chinotto, and Kachai lemon can serve as potential sources of functional components, bioactive compounds, and antioxidants, which can be explored for further application in the processing industry for nutritional security.

Influence of soil microbes on plant pathogens of Artocarpus heterophyllus in nokrek biosphere reserve of Meghalaya

Influence of soil microbes on plant pathogens of Artocarpus heterophyllus in nokrek biosphere reserve of Meghalaya

Relationship between soil microbes and plant pathogens of Ziziphus zizyphus in Nokrek biosphere reserve of Garo hills of Meghalaya

Wild Indian plum (Ziziphus zizyphus), locally known as ‘angkil’, is a rich source of vitamin C and contains minerals and proteins. The ripe fruits are mostly consumed fresh. Processed products like candy, pickle, chutney and jelly are also prepared from fruits. The young plants are used for making hedges and leaves are used as fodder. The objective of the study was to identify the disease causing pathogens in Z. zizyphus and soil microbes inhabiting the rhizosphere of this plant in the three zones of Nokrek Biosphere Reserve, as well as to assess the relationship between soil microbes and occurrence of plant pathogens. Eight diseases caused by fungal pathogens and one disease caused by algae were observed. Change in zone showed significant influence on occurrence of plant pathogens. Occurrence of soil microbes in the rhizosphere was significantly influenced by change in soil depth and season. Soil microbes were found to be more in top soil than subsoil. Soil microbes Fusarium oxysporum and Phytophthora palmivora inhabiting the rhizosphere of Z. zizyphus at 0–15 cm soil depth had a significant positive association with plant pathogens, Colletotrichum acutatum, Cercospora ziziphii and Cladosporium ziziphii while exerting an antagonistic effect on pathogens like Oidium erysiphoides, Colletotrichum gloeosporioides and Alternaria alternata. Soil microbe Penicillium terrestre at 0–15 cm soil depth showed significant association with pathogens O. erysiphoides and C. gloeosporioides. Soil microbes at 15–30 cm soil depth had no significant influence on occurrence of plant pathogens.

Plant pathogens and soil microbes associated with Citrus indica in Nokrek biosphere reserve of Meghalaya

Citrus indica Tanaka, commonly known as Wild Indian Orange, is the most primitive of all citrus fruits found around the world. This plant is found growing in the wild only in Nokrek Biosphere Reserve of Garo Hills, Meghalaya. The plant is of great significance among the local people for various traditional medicines and spiritual purposes. The objective of the study was to identify the disease causing pathogens and soil microbes inhabiting the rhizosphere of C. indica in the three zones of Nokrek Biosphere Reserve, as well as to assess the relationship between soil microbes and occurrence of plant pathogens. Nine diseases caused by fungal pathogens and one disease caused by algae were observed. Change in zone exerted a significant influence on occurrence of pathogens in C. indica. Occurrence of soil microbes in the rhizosphere of C. indica was significantly influenced by change in zone, soil depth and season. Soil microbes were found to be more in top soil than sub-soil. Among the identified soil microbes, Aspergillus flavus, Penicillium digitatum and Rhizopus nigricans were the dominant ones. At 0–15 cm soil depth, soil microbes Curvularia lunata, Drechslera oryzae and Aspergillus niger exerted positive influence on occurrence of plant pathogens Capnodium citri, Cephaleuros virescens, Alternaria citri and Mycoshaerella citri, while plant pathogens like Acrosporium tingitanium, Diaporthe citri, Penicillium digitatum and Phytophthora citrophthora were antagonistically affected. At 15–30 cm soil depth, soil microbe Drechslera oryzae positively influenced the occurrence of plant pathogens Alternaria citri and Cephaleuros virescens, while Colletotrichum falcatum at 15–30 cm soil depth positively influenced the occurrence of plant pathogens Acrosporium tingitanium and Diaporthe citri.

Effect of coal mining on soil physico-chemical properties of Nokrek Biosphere Reserve of Meghalaya, northeastern India

Mining causes massive damage to landscape and biological components of an ecosystem. Due to extensive and unmanaged coal mining in the southern part of Nokrek Biosphere Reserve of Meghalaya, the area has been turned into degraded land since nutrient deficient sandy spoils are hostile for the growth and regeneration of plant communities. Soil is sandy to sandy loam and red, brown to dark brown in colour. The physico-chemical properties of the soil were greatly affected due to coal mining. There is an increased acidity i.e. from 6.00 in the undisturbed forest (control site) to 3.50 in the coal mine spoil since abandoned mine spoil discharge acidic water that are enriched with iron and other metals and metalloids. Apart from this, soil nutrients are greatly depleted. The core zone soils are rich in organic matter and nutrients whereas coalmine spoils show sign of degradation especially in the nutrient content.

Vegetation Change During Recovery of Shifting Cultivation (Jhum) Fallows in a Subtropical Evergreen Forest Ecosystem of North- Eastern India

An understanding of vegetation change on jhum fallows undergoing recovery following shifting cultivation is vital for developing a rehabilitation strategy for shifting cultivation areas. However, the pattern of vegetation change during the recovery of shifting cultivation fallows is not well-studied. Therefore, the present study was carried out in a subtropical forest ecosystem in the buffer zone of Nokrek Biosphere Reserve in north-eastern India where shifting cultivation is being practiced extensively. The species composition and other plant community attributes were studied in 1-year, 3-year, 6-year and 12-year old shifting cultivation (jhum) fallows and were compared with an undisturbed forest in the adjoining core zone of the Biosphere Reserve. The rate of recovery of various community attributes such as species dominance and diversity, tree species population structure, stratification and life form spectrum was, in general, slow. The young fallows exhibited high dominance and low equitably which slowly progressed towards high equitability as recovery progressed with increasing age of the fallows. The number of species recorded in the 12th year of fallow represented about 86% of the total species in the undisturbed forest. Other community attributes of the forest regrowth on the 12-year old fallow reached up to 70-80% of the values recorded in the undisturbed forest community indicating that there was good recovery of species richness and other community attributes on the 12-year old fallows if there was no disturbance.

Phenology and Geographic Extension of Lycophyta and Fern flora in Nokrek Biosphere Reserve of Eastern Himalaya

Tropical and subtropical hilly vegetation in Himalayan regions are well suited for the taxonomical research because of the diverse habitat available in close proximity and the regions promote high species richness and endemism due to variation in slopes, soils, rocks, microclimate, exposure, latitude and altitude. Pteridophytes have evolved to fill the ecological niche between the angiosperms and the gymnosperms. During the course of recent study towards the pteridophytes of Nokrek Biosphere Reserve in eastern Himalaya, a few new taxa are described and geographical distribution extension of several previously reported species have also come to light. Studies based mainly on collections made during the last 6 years have resulted in the revised description of the 19 species of lycophyta and ferns viz. Asplenium gueinzianum, Argostemma perakense, Asplenium sinense, Cyclosorus crinipes, Diplazium pseudosetigerum, Hymenasplenium cheilosorum, Lemmaphyllum microphyllum, , Lemmaphyllum rostratum, Loxogramme chinensis, Lygodium microphyllum, Microlepia hancei, Microlepia rhomboidia, Neocheiropteris zippelii, Pleopeltis macrosphaera, Pseudocyclosorus falcilobus, Pteriscadieri var. hainanensis, Pyrrosia lanceolata, Pyrrosia longifolia and Tectaria paradoxa from the Meghalaya state recorded for the first time. Full species citations, taxonomic notes, phenology time, chromosome counts, ecology, specimen studied, previously known distributions and citation records are given for all taxa. Recent collections show the richness of the flora of Meghalaya and permit more accurate taxonomic and phytogeographic comparisons with lycophyta and fern flora from adjacent areas.

A Survey of Ethnomedicinal Plants Utilized by the Indigenous People of Garo Hills with Special Reference to the Nokrek Biosphere Reserve (Meghalaya), India

The present study documented pharmaceutically important plant resources used in primary health care of ethnic Garo tribes from Eastern Himalayas (Nokrek Biosphere Reserve [NBR], India). In order to document information on medicinal plants and to maximize the collection of indigenous knowledge of Garo tribes, 12 traditional healers were identified using the Participatory Rapid Appraisal approach. Data were collected through open-end interviews with traditional healers, between 2007 and 2011. A total of 157 plant species representing 134 genera and 81 families were found to be commonly used in the treatment of 67 health-problems. More than one-fourth of the plant species were used in the treatment of cough, flu, and cold, which are prevalent ailments in the study area. The leaves, root, rhizome, and tuber were the most commonly used plant parts while decoction was the most common method of drug preparation.

Recollection of Hemiorchis Pantlingii King after a Century from Meghalaya

The paper deals with taxonomy of Hemiorchis pantlingii King (Zingiberaceae) collected from Nokrek Biosphere Reserve (NBR), Meghalaya. The species is a new record for Garo Hills District and is rediscovered after a gap of about 123 years from Meghalaya. The photographs of H. pantlingii King provided for easy identification.

Contribution to the pteridophytic flora of India: Nokrek Biosphere Reserve, Meghalaya

Nokrek National Park, located approximately 40km from Tura town in West Garo Hills district of Meghalaya, India, was added to the list of Biosphere Reserves by UNESCO in May 2009. Since there is no previous report from this area, the pteridophytes of the Nokrek Biosphere Reserve are catalogued in the present study. The checklist consists of 113 taxa (98 ferns, 15 fern allies), of which 25 species are newly reported for the Meghalaya State (Selaginella involvens, Selaginella semicordata, Selaginella subdiaphana, Selaginella tenuifolia, Asplenium gueinzianum, Asplenium perakanse, Microlepia hancei, Microlepia rhomboidea, Dicranopteris linearis, Coniogramme procera, Bolbitis sinensis, Loxogramme chinensis, Lygodium microphyllum, Lemmaphyllum microphyllum, Lemmaphyllum rostratum, Pleopeltis macrosphaera, Pyrrosia lanceolata, Pyrrosia longifolia, Pteris biaurita ssp. walkeriana, Pteris grevilleana, Tectaria fuscipes, Cyclosorus crinipes, Pseudocyclosorus falcilobus, Diplazium apicisorum and Diplazium pseudosetigerum) and 43 species are new for all the three Garo Hill districts of the Garo Hills in the Meghalaya State.

Faunal diversity of Cladocera (Crustacea: Branchiopoda) of Nokrek Biosphere Reserve, Meghalaya, northeastern India

Thirty-four species of Cladocera, belonging to 24 genera and seven families, documented from the Nokrek Biosphere Reserve of Meghalaya indicate fairly speciose and diverse taxocoenosis and comprise 57.7% of species known from this state. Coronatella anodonta is the first confirmed report from India and two species are new records from Meghalaya. Disperalona caudata is an interesting Australasian element and a number of species show regional distributional importance. The Cladocera of the Nokrek Biosphere Reserve show tropical characteristics with Cosmopolitan > Cosmotropical species, and are characterized by a distinct richness of the littoral-periphytonic members of the Chydoridae as well as a paucity of limnetic elements. The species richness of Cladocera in various localities ranges between 11-24 (15 plus or minus 3) species.

Harpullia Arborea (Blanco) Radlk. - A New Record to Meghalaya

Harpullia arborea (Blanco) Radlk., is collected for the first time from Nokrek Biosphere Reserve, Meghalaya and is reported as a new record for the state.

Coal mining impact on vegetation of the Nokrek Biosphere Reserve, Meghalaya, India

Extensive coal mining activity in the buffer zone of the Nokrek Biosphere Reserve (NBR) in Meghalaya, India, has led to habitat degradation and a landscape dotted with mine spoils. The present study analyses the impact of coal mining on different aspects of vegetation of the NBR. For this purpose, three coal mining sites, viz. Budugiri, Buduwathegiri and Faramgiri, were randomly selected from the 18 sites present within the biosphere reserve. It was found that the total number of species was much less in mined areas than un-mined areas. Tree and shrub populations showed a drastic reduction in their species composition due to coal mining. The density of trees, shrubs and herbs in mined areas was significantly lower than in un-mined areas at all three sites. The basal area of trees follows the same trend as density. The dominance of plant species was shared by many species both at un-mined and mined sites. Fifteen species of trees, four shrubs and 28 herb species were found in mined sites, while 27 tree species, four shrub species and 16 herb species were found only in the un-mined sites. The dominance–diversity curves for the mined sites resemble the broken-stick series model, which indicates less species occurring in these areas and also represents a stressed environment with conditions unfavourable for plant growth. Shannon's diversity index for tree species was low in the mined sites, which indicates adverse impacts from mining. The diversity index for herbs increased with mining, suggesting that the mining operation enhanced the colonisation of certain species in the newly created habitats. Trees of the medium girth class dominated both the mined and un-mined areas at all three sites. The density of trees, irrespective of their girth classes, was lower in the mined areas than the un-mined areas. There was not much variation in the distribution pattern of the species as most tree species showed contagious distribution patterns both in the un-mined and mined areas.

Faunal diversity of rotifers (Rotifera: Eurotatoria) of Nokrek Biosphere Reserve, Meghalaya, India

Plankton samples collected from the Nokrek Biosphere Reserve of Meghalaya (Northeast India) revealed 70 species of Rotifera belonging to 24 genera and 15 families. Eight species are new records from the state of Meghalaya. The Oriental Lecane blachei and the palaeotropical L. unguitata are biogeographically interesting elements. The Rotifera taxocoenosis of Nokrek Biosphere Reserve is characterized by a distinct richness of the tropic-centered genus Lecane, paucity of Brachionus species, greater diversity of littoral-periphytonic elements and a general tropical character with cosmopolitan (71.4%) > tropicopolitan (17.1 %) species.

ISSR polymorphism in Indian wild orange ( Citrus indica Tanaka, Rutaceae) and related wild species in North-east India

Inter simple sequence repeats (ISSR) polymorphism in Citrus indica Tanaka (Rutaceae), an endemic and threatened wild species, was examined along with three other closely related wild taxa ( C. medica L., C. latipes (Swingle) Tanaka, and C. sp. ‘Memang athur’) by analyzing 53 representative accessions sampled from North-east India. Jaccard's similarity values among 53 accessions of Citrus ranged from 0.46 to 0.97 (average = 0.75). Genetic similarity values among all the 34 accessions of C. indica were found in the range of 0.82 to 0.97 with an average of 0.90. Heterozygosity (Ht = 0.123) and Shannon's information index ( I = 0.188) values estimated for C. indica revealed significantly low level of genetic variation within the species. UPGMA dendrogram grouped all 53 accessions of Citrus into four major clusters: Cluster I – C. latipes; Cluster II – C. medica; Cluster III – ‘Memang athur’ and Cluster IV – C. indica. The dendrogram placed all the 34 accessions of C. indica in five sub-clusters under Cluster IV. The placement of C. indica accessions in various sub-clusters and groups in the dendrogram was based on molecular differentiation of individual accessions rather than their geographical origin. Very low genetic diversity and destruction of its natural habitat pose serious threat to C. indica even in the Citrus Gene Sanctuary in Nokrek Biosphere Reserve (NBR) in Meghalaya. Low genetic variability, heterozygosity and Shannon's information index in C. medica, C. latipes and ‘Memang athur’ are also concerns that need to be addressed for developing appropriate strategies to conserve the genetic diversity extant in these valuable genetic resources.

Spatial modelling for biological richness analysis in Nokrek biosphere reserve — north-eastern India

Spatial modelling for biological richness analysis in Nokrek biosphere reserve — north-eastern India

Changes in microbial biomass and activity in relation to shifting cultivation and horticultural practices in subtropical evergreen forest ecosystem of north-east India

Abstract The present study conducted in the Nokrek biosphere reserve (BR) of Meghalaya in north-east India aimed at analyzing the impact of human activities such as shifting agriculture (‘Jhum’) and horticultural practices on temporal and spatial changes in microbial biomass and dehydrogenase and urease activities in soil. Microbial biomass-C (MBC) and -N(MBN) as well as dehydrogenase and urease activities were significantly (P