Anjana Devkota

... 1990-9233 © IDO SI Publications, 2010 Effects of Different Light Levels on the Growth Traits and Yield of Centella asiatica Anjana Devkota and Pramod Kumar Jha Department Central ... 9. Zobel, DB, PK Jha, MJ Behan and UKR Yadav, 1987 ... Ratna Book Distributor, Kathmandu 10 ...

Additional file 1: Table S1. Total Survey sites showing total number of plants infested by Puccinia abrupta var. partheniicola and rust incidence in different locations of Kathmandu Valley. Fig. S1. Photographs of Parthenium hysterophorus infested by Puccinia abrupta var. partheniicola in different severity classes (A - healthy plant with no infestation; B – only a few leaves infested without any apparent impact on growth; C – premature senescence of some leaves but not apparent impact on inflorescence; D – death of about 50% leaves with apparent impacts on inflorescence but not senescence of plant; E – death or senescence of plant) (A, D: S. Maharjan; B, C, E: BB Shrestha). Fig. S2. Microscopic image of urediniospores of Puccinia abrupta var. partheniicola stained in cotton blue

Abstract: The laboratory tests were conducted to evaluate the allelopathic potential and phytochemical study of the four selected medicinal plants Ageratum conyzoides, Eclipta prostrata, Cannabis sativa and Woodfordia fructicosa. The aqueous extract bioassay of the plants with stem and root were conducted on the two test seeds Triticum aestivum (wheat) and Pisum sativum (pea) by filter paper method. Germination, seedling growth and biomass production were observed under the allelopathic study whereas under phytochemical study qualitative or presence or absence and quantitative or crude amount of the phytochemicals present were also estimated. For the allelopathic studies the germination and seedling growth of wheat and pea test species under the different concentrations 2 %, 4%, 6%, 8 % and 10 % of the stem and root extracts of the plants under study were carried out. Increased concentration of the aqueous extracts of the plants increased the inhibitory rate or decreased the germina...

The present research aims to know the regeneration status of community managed Shorea robusta (Sal) forests; managed for 6-21 years in Tanahun district, a part of Gandaki Province, Nepal. These forests were categorized into two groups according to management duration (more than 10 years and equal or less than 10 yrs). The regeneration status of the forest was estimated by calculating the density of each species in each developmental phase (seedling, sapling and tree). The total tree density of community forest managed for more than 10 years (MCF forest; 1230 plants/ha) was less than the community forest managed for equal or less than 10 years (LCF forest; 1314 plants/ha). The results suggest that the size class distribution of the trees resembling inverse-J shaped indicates the good regenerating capability of both forests. After the handover of forests to the community, Sal density had increased rapidly in both the forests. Community management had a significant positive impact on t...

The urban air pollution is a major environmental concern, particularly in the developing countries and in their major cities. In the present study an attempt has been made to assess the air pollution effect on micromorphological and biochemical parameters of Callistemon citrinus and Lagerstroemia indica. Biochemical parameters were analyzed by using standard protocol. one-way analysis of variance was performed with SPSS software, v. 20.0, and Duncan test (p ≤ 0.05) was used to compare averages of all measured biochemical parameters and micromorpholgical features. There was a decrease in number of stomata of both species at highly polluted site compared to less polluted site (control). Stomatal index of both species was found to be reduced in polluted site when compared to control. The number of clogged stomata was less in control area samples when compared to polluted sample. A number of epidermal cells were significantly decreased at heavily polluted site. Total chlorophyll content...

A b s t r a c t. The influence of water stress on growth and yield of Centella asiatica, a traditional medicinal herb of Nepal, was carried out in a pot experiment. Variation in different growth traits of Centella asiatica was investigated using vegetative clones of one population. The plantlets were grown in earthen pots containing soil, sand and vermicompost and treated with different levels of water stress (30, 70, 100, and 125% of pot capacity by mass). The experimental design was completely randomized and each treatment was composed of forty plants. An array of vegetative traits including: number of leaves, petiole length, specific leaf area, number of primary branches, and plant biomass was examined. Growth traits such as root length, leaf area and number of flowers per ramet demonstrated significant variation in response to water stress. The results suggested that plants irrigated to 100% pot water capacity showed highest growth and plant biomass production. K e y w o r d s: ...

Ageratum houstonianum Mill. (Asteraceae) leaves extract (in distilled water and methanol) was evaluated against five phytopathogenic fungi: Alternaria brassicae, Botrytis cinerea, Fusarium oxysporum, Phytophthora capsici and Sclerotium rolfsii at different concentrations (50, 100, 150, 200, and 250 mg/mL). The phytochemical screening depicted the presence of terpenoids, saponins, flavonoids, tannins and alkaloids. The activity test of extracts against fungi was determined by poisoned food technique and linear mycelium growth reduction (LMGR) percentage was calculated. Methanol crude leaf extract had higher antifungal potential than the distilled water extract. Aqueous and methanolic extracts of leaves of A. houstonianum greatly reduced the mycelium growth of tested fungi, which can be used for the disease management.

Antifungal activities and phytochemical screening of Xanthium strumarium (Asteraceae) was carried out in laboratory. Distilled water and methanol extracts of the leaves of plant was prepared. Five phytopathogenic fungi: Alternaria brassicae, Botrytis cinerea, Fusarium oxysporum, Phytophthora capsici and Sclerotium rolfsii were tested at different concentrations (50 mg/ml, 100 mg/ml, 150 mg/ml, 200 mg/ml, 250 mg/ml) of selected plant extracts. The phytochemical screening depicted the presence of terpenoids, saponins, flavonoids, tannins and alkaloids. The antifungal activity of extracts was determined by poisoned food technique; and linear mycelium growth reduction (LMGR) percentage was calculated. The distilled water extracts inhibited the growth of fungal mycelium while methanolic extracts completely inhibited (100%) the growth of some selected fungi at higher concentrations. Fusarium oxysporum was the most susceptible fungus while A. brassicae and B. cinerea were the most resistan...

Biological monitoring and assessment studies due to urban-road pollutants were carried out using Air Pollution Tolerance Index (APTI) of plants. Four plant (leaf) parameters--namely ascorbic acid, total chlorophyll, relative water content and leaf extract pH were combined together in a formulation signifying the APTI of plants. APTI was calculated for five different shrub species viz. Bougainvillea glabra, Duranta repens, Lantana camara, Ricinus communis and Sambucus hookeri growing in three different areas, i.e. control area and along the roadsides in Kathmandu valley. The control site was selected in the Tribhuvan University, Campus area. Reduction in total chlorophyll content and pH was found in the leaf samples of all selected plants collected from less polluted sites (control) when compared with samples from more polluted site, whereas APTI, ascorbic acid and RWC were found to be higher in the plant samples of more polluted site as compared to less polluted site (control). From...

Antibacterial activities of Xanthium strumarium L. (Asteraceae) was carried out in laboratory. Distilled water and methanol extracts of the leaves of plant was prepared. The antibacterial activity was studied against six pathogenic bacteria, three gram negative: Klebsiella pneumoniae (ATCC 15380), Proteus mirabilis (ATCC 49132), Escherichia coli (ATCC 25922) and three gram positive: Bacillus subtilis (ATCC 6633), Enterococcus faecalis (ATCC 29212), Staphylococcus aureus (ATCC 25932) at different concentrations (50 mg/ml, 100 mg/ml, 150 mg/ml, 200 mg/ ml, 250 mg/ml) of leaf extracts of X. strumurium. The phytochemical screening depicted the presence of terpenoids, saponins, flavonoids, tannins and alkaloids. The antibacterial activity of extracts was determined by disc diffusion method and zone of inhibition (ZOI) was measured. Gram negative bacteria was found more resistant than gram positive bacteria. The most susceptible bacterium was S. aureus while the most resistant bacterium w...

The aqueous (distilled water) and alcoholic (methanol) crude extract from the leaves of invasive alien plant species Ageratina adenophora and Ipomoea carnea ssp. fistulosa were evaluated against six human pathogenic bacteria, three Gram negative: Escherichia coli (ATCC 25922) , Klebsiella pneumoniaea (ATCC 15380) and Proteus mirabilis (ATCC 49132) and three Gram positive: Enterococcus faecalis (ATCC 29212) Bacillus subtilis (ATCC 6633) and Staphylococcus aureus (ATCC 25923) using disc diffusion method. Different concentrations of plant extracts (50 mg/ml, 100 mg/ml, 150 mg/ml, 200 mg/ml and 250 mg/ml) were applied and diameter of zone of inhibition (ZOI) of bacterial growth were recorded. Both plant extracts showed antibacterial activity against Gram positive and Gram-negative bacteria. Methanolic extract of plant extracts exhibited good activity against tested bacteria when compared to aqueous extract. Among tested plants I. carnea ssp . fistula was more active than A. adenophora ....

Four community-managed Sal forests in Dadeldhura district of Nepal were selected for the assessment of carbon stock. The stratified random sampling method was applied to measure the field data from 105 sample plots of 100 m2. The carbon stock of trees and shrubs was estimated using Chave allometric equations for moist forests. The study found that the community forests stored carbon stock ranging from 148.5 to 202.3 Mg ha–1 (mean: 175.5 Mg ha–1). The community forests managed for a longer duration have higher carbon stock than the community forests managed for a shorter duration. From the study, it can be concluded that these forests have been acting as a storehouse of the carbon. So, we can infer that community management has had a positive impact on increasing the carbon stock of forests and thus on the mitigation of global climate change. This study contributes to the understanding of the role of community forests in mitigating the effects of global climate change.

... 1990-9233 © IDO SI Publications, 2010 Effects of Different Light Levels on the Growth Traits and Yield of Centella asiatica Anjana Devkota and Pramod Kumar Jha Department Central ... 9. Zobel, DB, PK Jha, MJ Behan and UKR Yadav, 1987 ... Ratna Book Distributor, Kathmandu 10 ...

Wetlands are areas where water is the primary factor controlling the environment, associated plant and animal life. The present study has been conducted to investigate the environmental variables of water and to make a quantitative analysis of aquatic macrophytes. Five lakes, i.e. Tamor, Beeshazar, Kingfisher, Athaieshazar and Chepang of the Chitwan National Park were studied during the post-monsoon season. Four different sites were studied for each lake. 12 replica of water samples were collected from each site of the lakes and environmental variables of water i.e. pH, temperature, dissolved oxygen, total alkalinity, conductivity, total hardness, nitrate, inorganic phosphorus, total solid matter and free CO2 were analyzed. Macrophyte floras were collected during field sampling with the help of a 1m×1m light wooden quadrat and herbaria were prepared following the standard technique. Altogether 10 quadrats (five paired quadrats) were plotted in each site of the study area. Data obtai...

The effect of variation in soil composition on growth vigour of Centella asiatica (L) Urb. was investigated in greenhouse of Central Department of Botany, Tribhuvan University,Kathmandu. Variation in different growth traits of Centella asiatica was investigated using vegetative clone of genome from one population in Kirtipur, Kathmandu, Nepal. We chose soil composition type as the treatment factor to study variation in growth traits as well as to know the best type of composition of soil for cultivation purpose. We raised plants in each of six soil compositional type and examined an array of vegetative traits like: number of leaves, petiole length, specific leaf area, number of primary branches and plant biomass. Most of the observed growth traits demonstrated significant variation in response to soil type. The C. asiatica plant can maximize growth and yield in habitat with sandy loam rather than clayey soil.

In present study, the antifungal activity and phytochemical screening of the leaves of three invasive alien plant species of Aster family viz. Ageratum haustonianum, Ageratina adenophora and Parthenium hysterophorus were carried out in laboratory. Eight phytopathogenic fungi; Alternaria alternate, Alternaria brassicae, Botrytis cinerea, Exserohilium sp, F. moniliforme, Fusarium oxysporum, Phytophthora infestans, and Sclerotium rolfsii were tested against leaves extract of three plants. Aqueous and methanolic extracts of three plants at four different concentrations viz. at 50 mg/ml, 100 mg/ml, 150 mg/ml & 200 mg/ml were tested on phytopathogenic fungi using the disc diffusion method. In vitro antifungal activity were screened by using Potato Dextrose Agar (PDA) media. The qualitative phytochemical analysis depicted the presence of saponins, alkaloids, glycosides, flavonoids, glycosides and coumarins in the plants. Results showed broad spectrum antifungal activity against tested fung...

Centella asiatica is an important ethnomedicinal plant. Effect of integrated manuring on growth of Centella asiatica was investigated using vegetative clones from Kirtipur, Kathmandu. The plantlets were grown in earthen pots containing soil, with integrated manuring (Urea(%) : FYM(%), 75:25; 50:50; 25:75), individual manuring (100 % Urea, 100 % FYM) and control conditions (no manure). The experimental design was completely randomized and each treatment had forty plants. We examined number of leaves per ramet, petiole length, specific leaf area, number of primary branches, number of flowers per ramet and plant biomass. The number of leaves per ramet, leaf area and number of flowers per ramet were significantly higher in integrated manuring than other treatments. Biomass production in integrated manuring (50 % Urea and 50 % FYM) was seven times higher than in control; it was five times higher than in complete organic manuring (100 % FYM) and 1.5 times higher than in inorganic manuring...

Background Partheniumhysterophorus is a noxious invasive weed in tropical and subtropical regions of the world, including Nepal. Among 11 species of biological control agents released to control P. hysterophorus in Ausrtalia, winter rust Puccina abrupta var. partheniicola arrived fortuitously and has established in Kathmandu Valley, Nepal, nearly a decade back. However, the prevalence and effectiveness of this rust as a biological control agent in Kathmandu remain unknown. To address this knowledge gap, a roadside survey was done at an interval of 2 ± 0.25 km in Kathmandu Valley to assess the P. abrupta var. partheniicola incidence and its impacts on P. hysterophorus. Infested individuals of P. hysterophorus were further divided into four severity classes (very low, low, medium, and high), and rust incidence was calculated. The impact of the winter rust on the growth of P. hysterophorus was assessed by comparing biomass and seed output of infested and non-infested individuals. Resul...

The present work was undertaken to assess the surface water quality and discuss the potability of water by analyzed data of bacteriological (total Coliform and Faecalform) characters and heavy metals content (Fe, Mn, Zn, Pb, Cr and Cu) in the water of Tinau river. The study was carried out in the year 2011/2012 by selecting four spots within three different seasons: winter, summer and rainy. For bacterial enumeration, bacterial plate counts were carried out using the pour plate method with nutrient agar; while for determination of heavy metal concentration, Flame Atomic Absorption Spectro-photometry was used. The heavy metal content was within the range of WHO guideline for drinking purpose. However, on the basis of bacteriological parameters the water was not safe to consume without treatment. This study will also help to make aware those local people or adjacent farmers for proper management of waste disposal and also to minimize use of synthetic inputs.

The Rupa lake is the third largest and heavily tampered lake of Pokhara Valley. Physiochemical parameters like, water temperature, pH, dissolved oxygen (DO), total nitrogen (TN) and PO4-P and biomass of aquatic macrophytes were analyzed during pre and post-monsoon. Biomass ranged from 27.25g/m2–389.25g/m2 throughout the experimental period and the highest biomass was observed during post-monsoon period. Regarding the growth form, the highest biomass was represented by emergents (251.16 ± 95.16g/m2) and lowest biomass by submerged species (48.39 ± 7.27g/m2). The lake can be categorized as eutrophic.J. Nat. Hist. Mus. Vol. 26, 2012: 80-87

The study was carried out to evaluate the allelopathic effect of aqueous extract of rhizome and leaves of Costus speciosus Koen ex. Retz and Justicia adhatoda Linn. respectively on germination and growth of wheat (Triticum aestivum Linn.) and pea (Pisum sativum Linn.). Effect was assessed by recording their effects on germination and percentage growth of root and hypocotyle of test plants. However, the extent of inhibitory and stimulatory effect of extracts varied with the plant species. The extract reduced the germination of the test seeds. However, root and hypocotyle elongations of wheat and pea seedlings were significantly inhibited by the extract of studied plant parts, with the percentage of inhibition increased as the concentration of the extract increased. The observed allelopathic activity of the extract of both medicinal plants on the seed germination and seedling growth of wheat and pea was attributed to the presence of the allelopathic phytochemicals in medicinal plants....

Antibacterial activities of Xanthium strumarium L. (Asteraceae) was carried out in laboratory. Distilled water and methanol extracts of the leaves of plant was prepared. The antibacterial activity was studied against six pathogenic bacteria, three gram negative: Klebsiella pneumoniae (ATCC 15380), Proteus mirabilis (ATCC 49132), Escherichia coli (ATCC 25922) and three gram positive: Bacillus subtilis (ATCC 6633), Enterococcus faecalis (ATCC 29212), Staphylococcus aureus (ATCC 25932) at different concentrations (50 mg/ml, 100 mg/ml, 150 mg/ml, 200 mg/ ml, 250 mg/ml) of leaf extracts of X. strumurium. The phytochemical screening depicted the presence of terpenoids, saponins, flavonoids, tannins and alkaloids. The antibacterial activity of extracts was determined by disc diffusion method and zone of inhibition (ZOI) was measured. Gram negative bacteria was found more resistant than gram positive bacteria. The most susceptible bacterium was S. aureus while the most resistant bacterium w...

The aim of this research was to analyze physical and chemical characteristics of low altitude lake of Jagadishpur Reservoir, a Ramsar site in central Nepal lies about 197 m altitude. The reservoir water was studied for three seasons (rainy, winter and summer) to compare the changes in the parameters. Water quality in reservoir was found less favorable to aquatic organisms, with low pH and transparency, low dissolved oxygen (DO), and high nutrient concentrations (Nitrogen). The reservoir was found eutrophic in nature by nitrogen concentration and transparency criteria. The findings created a database for present status of low land water reservoir of Nepal, which can be used for the management of lakes as well as to study the impact on water quality.This study provided useful information for decision makers aimed to the conservation and sustainable management of the reservoir.Int. J. Appl. Sci. Biotechnol. Vol 6(3): 255-260

Aqueous and methanolic extracts of three plants at four different concentration viz. at 50, 100, 150 and 200 mg/ml were tested on clinical bacteria using the disc diffusion method. In vitro antibacterial activity was screened by using Nutrient Agar (NA). The qualitative phytochemical analysis depicted the presence of terpenoids, saponins, alkaloids, flavonoids, carotenes and glycosides in the plants. Results showed broad spectrum antimicrobial activity against the Gram-negative and Gram-positive bacteria. The methanol extract inhibited the growth of more bacteria compared to the aqueous extract. Results from in vitro study revealed that the antimicrobial activity might have been influenced by the solubility of active compound(s) in extracting solvent. Methanol extracts were relatively more effective than aqueous extract. Out of three invasive plants studied Parthenium hysterophorus seemed more effective, for inhibiting the growth of bacterial strains with maximum zone of inhibition ...

The management of invasive species is a complex, yet an essential component of biodiversity conservation and environmental management for sustainable futures. Despite a well-established linkage between biological invasions and human activities, the social dimension of invasive species management is less explored as compared totheecological aspects.Inrecentyears,theactiveparticipation oflocalcommunities,suchasassessing levelsof awareness and the selection of targeted species prioritized by communities, has been considered as a crucial element for managing invasive species. We conducted 32 focus group discussions (FGDs) including 218 participants in Chitwan-Annapurna Landscape (ChAL) of central Nepal, to assess knowledge and perceptions of agrarian and forest-dependent communities about invasive alien plants (IAPs), document the efforts of the community management of IAPs and prioritize IAPs for management. In the prioritization exercise, participants of each FGD were asked to rank three IAPs using scoring methods and to express their experience about the effects of the selected IAPs on humans and the environment. We found that communities had a living memory of the arrival of some of the IAPs in their locality without knowing the exotic nature of IAPs. Biodiversity loss, livestock poisoning, reduced agricultural production and forage supply, and negative impact on forest regeneration were reported as major negative impacts of IAPs. Communities also reportedly utilized IAPs for medicinal purposes, making compost by using biomass, and controlling floods and landslides. None of the government and non-governmental organizations working in the sectors of biodiversity conservation and environmental management has informed local forest-dependent agrarian communities about the consequences of biological invasions and management of IAPs. However, local communities had already started controlling the spread of some IAPs through manual uprooting. They were able to spot, identify and prioritize IAPs for management and some of the prioritized species were among the world's worst invasive species. Ageratum houstonianum was the top-ranked worst invasive species in agroecosystems while Chromolaena odorata and Ageratina adenophora were the top-ranked worst species in natural ecosystems. Our findings will be useful for guiding community education programs as well as the management of IAPs through formal policy and management plans, such as Nepal's National Biodiversity Strategy and Action Plan.

The effect of variation in soil composition on growth vigour of Centella asiatica (L) Urb. was investigated in greenhouse of Central Department of Botany, Tribhuvan University,Kathmandu. Variation in different growth traits of Centella asiatica was investigated using vegetative clone of genome from one population in Kirtipur, Kathmandu, Nepal. We chose soil composition type as the treatment factor to study variation

The lichens were collected from different altitudinal gradient ranges from 1500-2700 m. above sea level of Phulchowki hill. They were identified on the basis of their morphological, anatomical and chemical studies (colour reaction, thin layer chromatography and microcrystallography). A total of thirty-two species of lichens were identified which comprises nine families and ten genera. Among them family Parmeliaceae was largest one which comprises ten species. Key words: Lichens; Crustose; Foliose; Fructicose.   DOI: 10.3126/sw.v6i6.2633 Scientific World, Vol. 6, No. 6, July 2008 44-51

Study of lichens flora of Phulchoki showed that this area is rich in the lichen flora. A total of 250 different samples were collected from this area. The identification of collected specimens was done on basis of their morphological, anatomical and inimical studies. The lichens were collected from different altitudinal gradients extending from 1500-2700m. above sea level. The association of lichens with different substrata also studied. A total of 32 species of lichens were identified, which encompass 9 families and 10 genera. Among them family Parmeliaceae was largest.

Of the 30 species (including five varieties) of the genus Swertia in Nepal, nine have been reported to possess medicinal properties. Among these, S. chirayita is the most valuable species, with high demand in domestic and international markets. Nepal’s S. chirayita and related species are being recklessly exploited for commercial purposes. Two problems that have emerged with this lucrative market are (a) adulteration and fraudulent labeling of S. chirayita, and (b) depletion of S. chirayita and allied species from their natural habitats. To address the problem of adulteration and conservation, we studied molecular genetic diversity in S. chirayita populations and developed a molecular diagnostic tool for the purposes of authentication. We studied intra-specific genetic diversity in S. chirayita using Polymerase Chain Reaction (PCR)-based Random Amplified Polymorphic DNA (RAPD) technique. As a preliminary step, we identified optimal RAPD-PCR reaction and cycling conditions by varying...

A study on the regeneration of the Shorea robusta Gaertn in tropical forest of Palpa district was carried out during June-November, 2005. The altitude of study area ranged from 200 m -700 m asl in north facing slope. The study area was natural forest where, Shorea robusta and Terminalia alata, were dominant species .The size class distribution of Shorea robusta resembled the reverse J-shaped curve indicates better regeneration of sal in study area. Sapling and seedling density of Shorea robusta significantly correlated (p=0.01) but was no significant relation with soil parameter. Keywords: Regeneration; Shorea robusta; Size Class distribution Tropical Forest DOI: http://dx.doi.org/10.3126/sw.v9i9.5519 SW 2011; 9(9): 53-56   DOI: http://dx.doi.org/10.3126/sw.v9i9.5518

Viable seeds of paddy and barnyard grass in different concentrations of aqueous extracts ( 2, 4, 6, 8 and 10 %) of leaf, stem and root of Chromolaena odorata were germinated at room temperatures. The leaf extract had strong inhibitory effect on seed germination as well as linear growth of paddy and barnyard grass. The order of inhibition was leaf >stem >root on both tested seeds. Allelopathic effect increased with increased concentration of the extracts. Key Words: Allelopathy; Paddy; Barnyard grass; Aqueous extract; Root length; Shoot length. DOI: 10.3126/sw.v8i8.3854 Scientific World Vol.8(8) 2010 pp.73-75