Botany

A comparativ e study was performed to ev aluate the breakdown of leaf litter of two broad-leav ed tree species, i.e. Polyalthia longifolia and Rhododendron arboreum by an exotic earthworm species Eisenia foetida and an indigenous earthworm species Perionyx excavatus under laboratory condition. Methods of Haimi and Huhta (Biol Fertil Soil 10:17 8–183, 1990) were followed for the present study. The rate of decay , percent cellulose, hemicelluloses and lignin contents of the decomposing leaf litter of P. longifolia and R. arboreum were found to be higher in the sets treated with the two different earthworm species as compared to that of untreated sets where no earthworm was added. Though there was not much difference in the rate of leaf litter breakdown by two different earthworm species, the rate of litter breakdown by the exotic earthworm, E. foetida, was slightly higher as compared to the indigenous earthworm P. excavatus. Both the selected leaf litters treated with the different earthworm species exhibited significant positiv e correlations between percent biomass remaining, cellulose, hemicelluloses and lignin contents (p ≤ .001). Significant v ariation was observ ed in hemicelluloses of leaf litters in sets

The montane subtropical broad-leaved humid forests of Meghalaya (Northeast India) are highly diverse and situated at the transition zone between the Eastern Himalayas and Indo-Burma biodiversity hotspots. In this study, we have used inventory data from seedlings to canopy level to assess the impact of both biotic and abiotic disturbances on structure, composition, and regeneration potential of the Fagaceae trees of these forests. Fagaceae trees are considered as the keystone species in these forests due to their regional dominance and their importance as a fuel wood source, and also because they form an important component of climax community in these forests. Unfortunately, these forests are highly degraded and fragmented due to anthropogenic disturbances. We have assessed, for the first time, the restoration potential (i.e., capacity to naturally regenerate and sustain desired forest structure) of Fagaceae species in the genera Lithocarpus Blume, Castanopsis (D. Don) Spach, and Qu...

The Waxy locus of rice is a highly polymorphic region embedded with microsatellite repeats in the 5 0 UTR leader intron 1 region, 23-bp duplication (wx motif) in exon 2, SNPs in exons 4, 6 and 10, p-Sine-r2 element in intron 1 and TnR-1 element in inton 13. Of the 80 polymorphic sites detected on the Wx gene, 24 are located in p-Sine-r2 and TnR-1 elements, revealing a higher substitution rate of bases in these two regions. All the cultivars with chalky endosperm had the 5 0-AGTTATA-3 0 haplotype in intron 1 and 'A' to 'G' substitution at ?497 in exon 4. The AAC of starch from grains of all the accessions showed strong correlation (r=0.967) with GBSS-I activity in the grains. Based on the polymorphic sites of the Waxy locus and the GBSS-I activities, six allelic variants were defined which included wx, Wx op , Wx b , Wx in , Wx a2 and Wx a1 , respectively, corresponded to glutinous, very low, low, intermediate, highII and highI amylose classes. Phylogenetic tree developed from alignment matrix of nucleotide sequences of the Waxy locus identified wx, Wx b and Wx in alleles with japonica lineage of Oryza sativa and the Wx op , Wx a2 and Wx a1 with indica lineage.

Tree diversity and community composition in six sacred forests (SF) of Meghalaya were compared with those of six adjacent community forests (CF) to understand how protection provided to sacred forests by the communities impacts their diversity and community characteristics. The SFs harboured a greater number of tree species (187) compared to the CFs (56). Tree density in the SFs ranged from 750 trees ha −1 (MKSF) to 1470 trees ha −1 (MTSF) while in CFs, it was 875 trees ha −1 (ILCF) to 1236 trees ha 1 (NBCF). Among the SFs, the highest basal area was recorded in MNSF (56.89 m 2 ha −1) and least in NBSF (40.75 m 2 ha −1), while among the CFs tree basal area ranged from 23.7 m 2 ha −1 in MKCF to 36.0 m 2 ha −1 in MNCF. The canopy cover in SFs ranged from 73.3 to 86.2% while in CFs it ranged from 54.3 to 70.8%. Species rank abundance distribution (RAD) curve or dominance-diversity curve showed high equitability and low dominance in all the six SFs while the RAD curve showed high dominance and low equitability in all the six CFs. The dominance-diversity curve in the SFs followed a log-normal distribution whereas the CFs exhibited a broken stick distribution pattern. Among the CFs, Pinus kesiya was the dominant tree species in five out of six study sites. The dominant species were different for different SFs, which were Microtropis discolour (ILSF), Citrus latipes (MNSF), Castanopsis tribuloides (MTSF), Castanopsis armata (NBSF), Myrica esculenta (NKSF) and Taxus wallichiana (MKSF). SFs were characterized by high diversity and low dominance as seen in old-growth forests. Shannon's diversity index (H′) in the SFs ranged from 2.06 to 4.28 indicating high tree diversity, while in CFs it was 0.76-2.61 reflecting relatively lower diversity. Simpson's dominance index for trees was higher in CFs (0.09-0.73) than the SFs (0.02-0.26).

Variation in soil nutrient availability can influence the functional traits and performance of tree species in a forested landscape. We tested this hypothesis by studying the variations in leaf-traits, and N-and P-resorption efficiencies of a few evergreen (Myrica esculenta, Rhododendron arboretum and Lithocarpus dealbatus) and deciduous (Quercus griffithii, Engelhardtia spicata and Lyonia ovalifolia) tree species growing in montane subtropical old-growth and regenerating forests of Meghalaya, northeast India, varying in their soil characteristics. Trees of the old-growth forest stand, having greater soil total N and P, proved to be much efficient in their foliar nutrient resorption (mean = 42.0% for N and mean = 82.1% for P) and showed higher leaf nutritional quality compared to the regenerating forest stand. Deciduous species had greater N-resorption efficiencies (45.3-49.7%) than the evergreen species (23.6-56.9%) in the old-growth stand. However, in the regenerating stand, the evergreen species were better at resorbing both N (30.6-55.9%) and P (67.9-76.4%) from their leaves than the deciduous species (23.2-40.9% for N and 33.2-52.0% for P). Overall, phosphorus was the limiting nutrient for growth in both the functional groups, with relatively low concentrations in the soils of the two forest stands. The evergreen and deciduous trees in the old-growth forest are found to tightly conserve nutrients with higher leaf N and P concentrations and higher Nand P-resorption efficiencies than the regenerating forest stand. The study clearly indicates that soil fertility has profound effect on the internal nutrient cycling of evergreen and deciduous tree species.

Tea is a popular beverage and highest foreign exchange earning agricultural crop that contributes significantly to the Gross National Productivity (GNP) of India. India contributes to almost 31% of global production of tea. Tea Mosquito Bug, Helopeltis theivora Waterhouse is the most destructive polyphagous sucking pest of tea causing 10 - 50% crop loss. It was previously a minor pest but changes in environmental conditions and existing land cover over the past years has triggered its emergence as a menace for tea plantations of North East India. The present study attempts to assess the impact of land use and land cover on infestation intensity of the pest. Detailed land use land cover study on 8 tea gardens representing each agro-climatic zone shows that no individual land cover type has a direct relation on the insect infestation level. However, difference of areas under scrubland and cropland was found to be a causal factor for H. theivora infestation. The pest infestation level showed a decreasing trend with increasing cropland area as compared to scrubland area and vice versa.

In this study, we are presenting the results of the antioxidant activity of different TLC fractions isolated from the extract of Clerodendron colebrookianum leaves. Two different extracts (extract-1 and-2) of the leaves were prepared and their total flavonoid content was determined. Among the extracts, the one with higher total flavonoid content was selected for further separation using thin layer chromatography (TLC). Each TLC fractions including the crude extract-2 were individually assessed for total antioxidant capacity, 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging, hydroxyl radical scavenging activity. Their UV spectral analysis was also performed. As per the result, since the extract-2 was showing higher total flavonoid content than the extract-1, therefore, extract-2 was selected for further separation using TLC. Following TLC analysis of extract-2, three fractions were obtained with Rf values of fraction-1: 0.32, fraction-2: 0.53 and fraction-3: 0.82 respectively. The TLC fractions were shown to possess antioxidant activities. Also, the UV spectral analysis indicated that the TLC fractions may contain flavonoid component as they individually absorbed UV radiation in two different ranges between λ240~280 nm (band II) and λ300~550 nm (band I) as the flavonoids. Further studies will be conducted to identify the flavonoids present in each TLC fractions.
Keywords: Antioxidant activity, Clerodendron colebrookianum, Flavonoids

Forest ecosystems play an important role in regulating global carbon cycle. There are very few studies on biomass and carbon (C) stock from the community managed montane evergreen forests of India. In the present study three traditional forests: Sacred forests (SF), Restricted forests (RF) and Village forests (VF) were studied to analyze the level of disturbance, species diversity, stand characteristics, biomass and C stock. In each forest a belt transect of 20 m wide and 250 m long (0.5 ha) was laid for enumeration of all woody individuals having a diameter at breast height (dbh) of ! 5 cm. Species richness, density, basal area and population structure varied between the traditional forest types. The aboveground biomass (AGB) was 273 ± 55.5 in the SF, 195 ± 32.12 in the RF and 75.3 ± 17.1 Mg ha À1 in the VF whereas, the corresponding belowground biomass (BGB) was 59.53 ± 8.4, 44.48 ± 7.5 and 19.9 ± 4.3 Mg ha À1 , respectively. Overall, there was a 30% reduction of AGB in RFs and 70% in VFs as compared to the SFs. The mean AGBC stock was 129 ± 26.3, 92.49 ± 15.2 and 39 ± 5.7 Mg C ha À1 in SF, RF and VF. The BGBC ranged from a minimum of 6 to 34 Mg C ha À1 in the study sites. The AGB accumulation was greater in intermediate diameter classes (26 À 45.9 cm) in the RFs and VFs whereas in SFs the diameter class >65cm accounted to about 27-69% of the total AGB. Human disturbance had a strong influence on the species richness and stand characteristics that in turn influence the biomass and C stock in the community forests. It is emphasized that the village forests need to be provided with adequate protection for increasing the C storing potential.

Habitat fragmentation creates numerous small forest patches separated by human land use that may affect the compositional and structural attributes and ecosysem functions particularly the nutrient dynamics in forest ecosystems. We tested this hypothesis along a fragment size gradient in subtropical broadleaved forests in Cherrapunjee area of Meghalaya, northeast India following standard methods of vegetation sampling and nutrient dynamics. The study revealed that the structure and composition of woody species, shrubs and herbs varied significantly (p<0.05) along a fragment size gradient. Similarly, the leaf litter standing crop as well as total litter fall and annual N and P return through litter fall varied significantly (p<0.05) across fragments and were higher in the larger fragments as compared to the smaller fragments. Therefore, the results of the study collectively suggest that understanding the overall ecological implications of the effect of fragmentation on the structure and functioning of subtropical broadleaved forest ecosystem of Meghalaya, north east India, is imperative to outline pertinent conservation strategies.

The future of many tree species is at risk due to the rapid decline of the world's forests, over-exploitation for timber, seeds, oils, resins, fruits and bark. In addition, seed germination in many threatened species is convoluted due to various physical factors such as moisture, light and the presence of thick seed coat as well as physiological factors such as seed dormancy. Studies pertaining to seed germination, storage behaviour, dormancy-breaking techniques, particularly of threatened tree species at global level are limited. Therefore, the present study was conducted to assess the progress made in the field of seed germination as well as the challenges that exist in the regeneration of such species that are of conservation value. The results obtained from the analysis of 78 threatened tree species showed that moisture is a critical factor for recalcitrant seeds, while species with orthodox seeds require a pre-treatment for breaking dormancy. Although most of the studies on dormancy-breaking techniques have demonstrated the effectiveness of one or two methods on seed germination, a combination of treatments as well as use of plant growth regulators improved the ability of seeds to germinate. Water, light, nutrients and a favourable substratum are major regulatory factors that affect germination, growth and establishment of tree species. The findings emphasize the need to develop guidelines for proper seed handling and understand germination protocols necessary for ecosystem management that would aid both in maintaining biodiversity values and conservation of threatened species.

Present paper discussed the higher plant diversity in Pakke Wildlife Sanctuary and its fringe locality of East Kameng District, Arunachal Pradesh. The area is located within Himalaya Conservation Hotspot. Random phytogeographical and floristic study exposed the diversity of higher plant species distributed in tropical, subtropical and temperate zones of the sanctuary along its altitudinal gradient. Some of the species those include globally significant medicinal plants were found threatened in fringe localities but coherent efforts are needed to include these species under IUCN Redlist category. An appropriate conservation measure through active participation of local community is needed to save those valuable higher plants resources from extinction in near future.

It occurs on the forest floor of broad-leaved or coniferous trees (Takahashi et al., 1993) and is distributed in humid temperate regions of Japan, southern China, Taiwan, Myanmar, northern Thailand, Vietnam and Indonesia (Remizowa et al., 2017). P. sakuraii differs from its congener P. stellaris in having racemose inflorescence (vs. umbel or corymbose), capsule with rounded and moderately recurved carpels (vs. laterally flattened and strongly recurved carpels) (Remizowa et al., 2017). While studying the floristic account of Talle Valley Wildlife Sanctuary of Arunachal Pradesh, the authors collected some interesting specimens of a small yellow saprophytic plant growing on the decaying leaf litter, under the canopy of dense evergreen forests. After a critical examination of the specimens, consultation of relevant literature (

Alkaline phosphatase (E.C.3.1.3.1) is an extracellular enzyme which plays an important role in releasing of phosphorus from sediment which is an essential nutrient for sustaining primary and secondary productivity. It also acts as an indicator of environment pollution. In this present research work which is the first of its kinds, the relationship between alkaline phosphatase activity of the sediment with the various soil physicochemical parameters along with total bacterial count was worked out. For these a total of 20 bulk sediment samples were collected randomly from different sites of the brackish water systems of the east India and processed to determine alkaline phosphatase activity, total bacterial count and other soil physicochemical parameters. Descriptive and inferential statistics were used to analyze the data. It can be inferred from this study that the alkaline phosphatase activity in brackish water systems is influenced by the different soil physicochemical parameters and bacterial population.

We present a new record of the dogwood tree (Cornus kousa F. Buerger ex Hance subsp. kousa) (Cornaceae) from the Eastern Himalayas in India. This record extends the known geographical distribution of C. kousa from China, Republic of South Korea and Japan to Eastern Himalayas of the Indian biome. With this report, the distribution of the subspecies kousa is also extended from Japan and Korea to India. The species was discovered from Khangchendzonga Biosphere Reserve (27°06'-28°05'N, 88°02'-88°47'E) in the state of Sikkim in the Eastern Himalayas. This discovery modified the current distribution of C. kousa in the world.

Forest fragmentation was identified as the most important factor reducing the plant diversity of Kanchendzonga Biosphere Reserve (KBR) located between 27°06' and 28°05' North latitudes, and 88°02' and 88°47' East longitudes in the Eastern Himalayan state of Sikkim in northeastern India. In addition to fragmentation, several other anthropogenic and natural factors have brought about extreme pressure on the persistence of threatened species in KBR. Several ethno-medicinally important plant species inhabiting the forests of KBR are also under threat due to these factors. In addition, over-exploitation of their populations for their medicinal value has put additional pressure on these plant species, many of which have reached on the brink of extinction. Empirical assessment of their populations is a prerequisite for developing any effective in-situ conservation strategy. Therefore, the present research work was undertaken to prepare a list of ethno-medicinal plants, and their conservation status, and uses under traditional medicine system. The research aimed to assess the population ecology of threatened and ethno-medicinal plant species in relation to forest fragmentation. The habitat distribution modeling of the three study species viz., Swertia chirayita, Paris polyphylla and Panax bipinnatifidus was undertaken to characterize the habitats of the species and map their distribution within KBR. The spatial and temporal dynamics of their populations in forest fragments (FF) and continuous forest (CF) were studied to assess the impact of forest fragmentation on population ecology of these species. Their metapopulation status was ascertained, characterized and Population Viability Analysis (PVA) was performed. The extinction probability analysis was also undertaken to evaluate their extinction risk. Generation of these empirical data and analyses are expected to help in preparing an efficient management plan for the threatened ethno-medicinally important plant species of KBR. Ethno-medicinal Plants Species of KBR A detail inventory of ethno-medicinal plants species present in KBR was prepared both through primary and secondary survey. Primary data was collected through a questionnaire 1 survey among the forty traditional healers residing in 36 villages located around KBR. Prior Informed Consent (PIC) was taken before interviewing the traditional healers. The available literature was also consulted on medicinal uses of the plant species reported by the traditional healers. The plants so documented were classified based on their uses, ecologic distribution, taxonomic classification and threat status. A total of 105 ethno-medicinal plant species were recorded belonging to 64 families. Dominant families were Ericaceae and Zingeberaceae with five species each. Fabaceae and Araceae had four species each, while 12 families viz.