Botany

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Arsenic Contamination of Soils and Agricultural Plants through Irrigation Water in Nepal
(Faculty of Botany, 2008) Dahal, Binod Mani
This study was conducted in the irrigation area of Nawalparasi district which is known as highly contaminated by arsenic among the Terai districts of Nepal. The purpose of this study was to analyse the arsenic of agricultural plants due to irrigation with arsenic contaminated water and the role of phosphorus fertilization. It is hoped that the result of this study will help to develop guidelines to protect the food chain by arsenic contamination in Nepal which is an important issue of the Millennium Development Goal (MDG) regarding the food security. 65 % of all 52 wells showed an arsenic concentration higher than 0.05 mg L-1, which is the Nepal interim standard for drinking water. Overall, 36 % of the irrigation wells exceeded the FAO guideline value (0.1 mg L-1) for arsenic in irrigation water. A wide range of arsenic concentrations was observed in the irrigation water, ranging between < 0.05 and 1.014 mg L1 . The As(III) dominates in the water with a mean percentage of about 76%. The arsenic concentrations in the irrigated soils ranged from 6.1-16.7 mg kg-1. The arsenic content was significantly (p < 0.05) higher in the soils of the vegetable fields than in the soils of the rice fields. The arsenic content in different parts of plants decreased in the order of roots > shoots > leaves > edible parts. The mean arsenic content of edible parts (dry weight) decreased in the order of onion leaves (0.55 mg kg-1) > onion bulb (0.45 mg kg-1) > cauliflower (0.33 mg kg-1) > rice (0.18 mg kg-1) > brinjal (0.09 mg kg-1) > potato (< 0.01 mg kg1 ). The arsenic contents of different soil aggregate fractions and its correlation with Fe, Mn, Al and Ca were studied in a rice and a vegetable field. The investigated aggregate size fraction was 1 – 2 mm. Arsenic content was highest in the smallest aggregates. Under rice no distinct correlation of arsenic with Fe, Mn, Al and Ca was found. Under vegetables As showed a good correlation with Fe, Mn and Ca in the smaller aggregate fractions (≤ 0.63 mm). The laboratory experiment showed that the arsenic solubility was highly influenced by changes in the soil redox potential. The As solubility was increased about 5 fold after the addition of Di-Ammonium Phosphate (DAP) fertilizer under redox potential conditions (aerobic to anaerobic) while solubility of Fe and Ca was not affected. This indicates that Pfertilizer can solublize As through ion exchange processes.
Assessment of Road Side Trees in Kathmandu Valley for their Air Pollution Tolerance Index and Heavy Metal Biomonitoring Ability
(Institute of Science & Technology, 2023-07) Hamal, Jaya Prakash
Carbon Sequestration Potential in community managed Forests in Mahottari District of Central Nepal
(Institute of Science and Technology, Botany, 2015) Mandal, Ram Asheshwar
Forest carbon sequestration plays a significant role in mitigation and adaptation to the impacts of the climate change. The carbon sequestration is accounted as carbon credit for reducing emission from deforestation and forest degradation (REDD+) programme. On the other hand, increasing concentration of CO2 emission contributes to green house gases (GHGs), which are mainly responsible for global warming and consequence is impacts of climate change. These, both need intensive scientific records to assess them, the former needs the records of carbon stock change while the latter one needs the record of sources of GHGs emission particularly the CO2 and CH4 emission. Such researches are very limited in Nepal. Thus, this study is objectively carried out to assess the specieswise Importance value index (IVI) and carbon stock; to assess the carbon stock in community managed forests; to identify the carbon sequestration potential and confrontation for carbon trade; to evaluate the carbon stocks for sustainable management of forests; to appraise the plant biodiversity status and its relationship with the forest carbon stock; to identify drivers of deforestation and forest degradation and its effects on carbon stocks in community managed forests and to quantify the CO2 and CH4 emission from domestic fuel and livestock keeping of household living near to forest and distant from the forests. For this study, two types of data specifically biophysical and socio-economic data were collected. The biophysical data were collected from community managed forests like three from each collaborative and community forests as well as public plantations and community planted forests of Mahottari district. In addition, socio-economic data collection was focused on drivers of deforestation and forest degradation, which were collected from workshop with key informants. Meanwhile, Sahodawa and Maisthan villages were selected for assessing the CO2 and CH4 emission from fuel consumption and cattle keeping respectively, which are sources of climate change process drivers. The maps of forest areas were prepared and stratified using GPS coordinates. Latter, altogether 96, 80, 28 and 24 permanent sample plots were distributed randomly on the maps of collaborative forests, community forests, public plantations and community planted forests respectively. The randomized block design (RBD) was set so the data were collected using stratified random sampling from collaborative and community forests. Meanwhile, the complete random design (CRD) was set to gather data applying simple random sampling from public and community planted forests. Similarly, altogether 138 households were sampled randomly after well-being ranking such as rich, medium and poor, then the quantity of fuel consumption was recorded in the morning and evening for seven days during summer and winter seasons setting RBD. Next, the record of cattle keeping was noted in order to determine the CH4 and CO2 emissions. At the same time list of drivers of deforestation and forest degradation were also gathered. The biophysical data were analyzed using the biomass equation of Chave et al. The species wise IVI was also calculated and their ranking was evaluated to know the effect of carbon on IVI. Same biophysical data were used to find out the relationship between biodiversity and forest carbon. Moreover, soil carbon was calculated applying Walkley and Black Method. Meanwhile, the carbon stocks of community forests and collaborative forests were checked applying Biolley's "Check Method" - Method du-Control and Biolley's sustainable principle. Additionally, the relationships were evaluated between carbon stocks and species richness and between carbon stocks and Simpson's evenness. The socio-economic data were analyzed using descriptive analysis. It showed that, IVI of Shorea robusta was the highest about 68.59 in Tuteshwarnath CFM while this value of Gmelina arborea was the lowest 0.4 in Gadhanta- Bardibash CFM. Meanwhile, the carbon stock of Shorea robusta was the highest 50.43±0.43 t ha-1 and this of Desmodium oojeinense was the lowest 0.01 t ha-1 in Gadhanta- Bardibash CFM. In addition, there was effect of carbon stock in species ranking. It was found that the estimated carbon stock was the highest 274.67 t ha-1 in Gadhanta- Bardibash CFM while it was the lowest in 30.34 t ha-1 in Bisbitty public plantation. The estimated current annual carbon increment (CACI) was found to be highest 2.85 t ha-1 at third year in Chyandanda community forest. However, annual carbon loss (ACL) was recorded as leakage -1.68 t ha-1 from Banke- Maraha CFM. The net value of carbon sequestration potential was US$ 5967.62. Therefore, these community managed forests can be avenue for carbon trade under the REDD+ programme. Neither community forests nor collaborative forest showed sustainability performance based on Biolley's "Check Method" - Method du-Control and Biolley's sustainable principle. Here, the issues of sustainable forest management and biodiversity should be balanced equally. The estimated R2 values indicated that there is very weak relationship between species richness and carbon stock, however, the hump- shaped relationship was exist between them. The over exploitation, grazing and forest fire were major drivers of deforestation and forest degradation, which are affecting the carbon stock. Total quantities of CO2 emission were 4792.25 t and 9235.68 t in Maisthan and Sahodawa villages respectively from firewood consumption. The CH4 emissions were 160.58 and 157.66 t yr-1 in Maisthan and in Sahodawa villages respectively from the livestock keeping, which together may emit 7367.59 t CO2 equivalents but managing the CH4 emission through biogas can offer US$ 47568.35 certified emission reduction. Therefore, it can be concluded that community managed forests are potential for carbon trade. On the other it is essential to determine the drivers of deforestation and forest degradation to address them for REDD+ programme in Nepal as well as to determine the sources of CO2 and CH4 clearly to reduce them as measures of climate change adaptation and mitigation. Keywords: Carbon sequestration, CO2 and CH4 emission, REDD+, biodiversity, community forests, collaborative forests, public plantation, community planted forest.
Comparative Bioactivities of in Vivo and in Vitro Materials of Piper longum L. and Paris polyphylla Sm
(Institute of Science & Technology, TU, 2024-11) Thapa, Chandra Bahadur; Prof. Dr. Bijaya Pant, Dr. Hari Datta Bhattarai, Dr. Krishna Kumar Pant
Piper longum L. (Piperaceae) is a valuable tropical medicinal plant used to cure a variety of diseases. Similarly, Paris polyphylla Sm. (Melanthiaceae) is a temperate or subalpine vulnerable medicinal plant used to treat a variety of diseases. However, unsustainable utilization, illegal collection and export, habitat destruction, and climate change are threatening its survival in its natural habitats. As a result, their population in natural habitats is declining. On the other hand, most research activities focus on bioactivity and chemical analysis of in vivo parts; however, research on bioactivity and chemical analysis of in vitro-cultured calli is extremely limited. In the present study, the bioactivity of in vitro and in vivo cultured parts of P. longum and P. polyphylla were compared. The most effective medium for direct organogenesis by regeneration of multiple shoots (5.33±1.15) in P. longum from nodal explants was MS medium supplemented with 1.0 mg/L TDZ. The maximum number of roots (7.0±1.0) was regenerated in MS + 1.0 mg/L IBA from in vitro shoots. Plants were also regenerated by indirect organogenesis from leaf and node explants, and by somatic embryogenesis. Callus was induced from leaf explants in MS medium enriched with 2,4-D or 2.4-D + KN, while it was induced from nodal explants in MS media enriched with NAA only. Multiple shoots were obtained in MS + 0.25 mg/L TDZ (25.33±1.52) for leaf callus and 2.0 mg/L NAA (18.33±1.50) for nodal callus. Subsequently, the maximum number of roots was regenerated from in vitro shoots by using 0.5 mg/L IBA from the leaf callus and 2.0 mg/L NAA from the nodal callus. In addition, the maximum embryogenic/nodular calli with somatic embryos (SEs) were found in MS + 1.5 mg/L 2,4-D + 1.0 mg/L KN (28.33±3.05 SEs) for leaf callus, and 1.0 mg/L NAA (12.66±2.51 SEs) for nodal callus. Nodular calli with SEs were differentiated into plantlets/seedlings in MS + 0.5-2.5 mg/L TDZ and full-strength MS media without PGRs. Similarly, P. polyphylla was also propagated in vitro using leaf explants, in which the best media for callus formation and mini-rhizomes with root differentiation were MS + 0.25 mg/L 2,4-D + 0.5 mg/L KN and MS + 2.5 mg/L KN respectively. The dichloromethane (DCM) fraction of P. longum root showed the highest antioxidant activity (IC50: 134.81±1.16 µg/mL), the highest total phenolic content (TPC), and the highest total flavonoid content (TFC) compared to other extracts of in vivo parts and in vitro callus. It showed 100% growth inhibition against five bacterial strains, such as Pseudomonas aeruginosa, Escherichia coli, Acinetobacter baumannii, Staphylococcus aureus, and Bacillus subtilis, with the lowest minimum inhibitory concentration (MIC) of 5.0 mg/mL, and the minimum bactericidal concentration (MBC) of 8.35 mg/mL for S. aureus. It was more cytotoxic to brine shrimp nauplii (LC50: 156.78±5.49 µg/mL), while the crude extract of the fruit showed higher anticancer activity (IC50: 146.55±2.31 µg/mL) on U-2 OS and HeLa cell lines (LC50: 273.31±17.89 µg/mL). Similarly, the DCM fraction of the root showed higher inhibition of α-amylase (IC50: 365.21±31.021 µg/mL) and α-glucosidase (IC50: 489.07±27.966 µg/mL) compared to other extracts of in vivo parts and in vitro callus. In addition, callus suspension culture in MS medium showed that salicylic acid increased callus biomass compared to other treatments, while 100 mg/L phenylalanine resulted in the maximum antioxidant activity (IC50: 22.44±1.96 µg/mL), TPC, and TFC. Similarly, the DCM fraction of P. polyphylla showed the highest antioxidant activity (IC50: 197.06±0.635 µg/mL), TPC, and TFC compared to other extracts of rhizome and callus. It also showed 100% growth inhibition against the five bacterial strains tested, with the lowest MIC at 5.0 mg/mL and MBC at 7.5 mg/mL for E. coli. It was more cytotoxic on brine shrimp nauplii (LC50: 201.78±70.97 µg/mL). It also showed higher anticancer activity (IC50: 235.94±0.72 µg/mL) to HeLa cell lines, but the methanol fraction was more cytotoxic to MCF-7 cell lines (IC50: 211.36±0.57 µg/mL). However, the crude extract of the rhizome inhibited α-amylase (IC50: 95.45±8.71 µg/mL) and α-glucosidase (IC50: 51.40±8.62 µg/mL) more effectively than other extracts of rhizome and callus. In addition, suspension culture in MS medium revealed that salicylic acid increased callus biomass than other treatments, but liquid MS media supplemented with BAP+NAA resulted in the highest antioxidant activity, TPC, and TFC than phenylalanine or salicylic acid. LC-HRMS analysis of the DCM fraction of the root and crude extract of the callus of P. longum revealed a total of 27 compounds. Similarly, the DCM fraction of the rhizome and the crude extract of the callus of P. polyphylla exhibited a total of 31 compounds. Piper longum L. (पिपला) एक बहुमुल्य उष्णप्रदेशीय औषधीय गुण भएको बिरुवा हो, जुन विभिन्न प्रकारका रोगहरु निको पार्न प्रयोग गरिन्छ । त्यस्तै, Paris polyphylla Sm. (सतुवा) एक समशीतोष्ण वा हिमाली भागमा पाईने जोखिमयुक्त (Vulnerable) औषधीय गुण भएको बिरुवा हो, जुन विभिन्न प्रकारका रोगहरुको उपचार गर्न प्रयोग गरिन्छ । तथापि, दिगो उपयोगिताको अभाव, अवैध संकलन र निर्यात, बासस्थानको ह्रास र जलवायु परिवर्तनले प्राकृतिक बासस्थानमा यिनीहरुको अस्तित्वलाई खतरामा पारेको छ । फलस्वरुप, प्राकृतिक बासस्थानमा यिनीहरुको संख्या घट्दै गइरहेको छ । अर्कोतर्फ, अधिकांश अनुसन्धान गतिविधिहरु यी विरुवाहरुका प्राकृतिक परिवेशमा (in vivo) उत्पादन भएका विभिन्न भागहरुका bioactivity र रसायनिक विश्लेषणमा केन्द्रित छन् । तर तन्तु प्रविधिबाट (tissue culture) उत्पादित callus को bioactivity र रसायनिक विश्लेषणको अनुसन्धान अत्यन्त सीमित छ । तसर्थ, यस अनुसन्धानमा पिपला र सतुवाको प्राकृतिक परिवेशमा (in vivo) उत्पादन भएका विभिन्न भागहरु र कृत्रिम परिवेशमा (in vitro) उत्पादित callus को तुलनात्मकरुपमा bioactivity र रसायनिक विश्लेषणको अध्ययन गरिएको छ। Tissue Culture प्रविधि प्रयोग गरि कृत्रिम पोषक माध्यम (MS media) मा पिपलाको काण्डको आँख्ला (node) र पात (leaf) बाट स-साना बिरुवाहरु उत्पादन गरियो, अनि सतुवाको पातबाट पनि यसका बिरुवाहरु उत्पादन गरियो । पिपलाको आँख्लाबाट बिरुवाहरु उत्पादन गर्दा प्रत्यक्ष organogenesis विधिवाट र यसको पातबाट र सतुवाको पातबाट बिरुवाहरु उत्पादन गर्दा अप्रत्यक्ष organogenesis र somatic embryogenesis उपयुक्त देखियो । त्यसैगरी, पिपलाको आँख्ला र callus बाट धेरै संख्यामा टुसाहरु (Shoots) उत्पादन गर्नको लागी र सतुवाको callus बाट धेरै संख्यामा टुसाहरु (Mini-rhizome) उत्पादन गर्नको लागी MS पोषक माध्यममा TDZ र KN हर्मोनहरु उपयुक्त देखियो । साथै टुसाबाट जराहरु उतपादन गर्नको लागी MS पोषक माध्यममा IBA हर्मोन उपयुक्त देखियो । पिपलाको जराको Dichloromethane (DCM) extract ले अरु extract ले भन्दा बढी antioxidant activity, total phenolic content (TPC) र total flavonoid content (TFC) देखायो । यस extract ले ५ प्रकारका ब्याक्टेरियाहरु (Pseudomonas aeruginosa, Escherichia coli, Acinetobacter baumannii, Staphylococcus aureus र Bacillus subtilis) को बृद्धिलाई रोकेको देखायो । त्यसैगरी, यसले Brine shrimp झिंगाका लार्भाहरुलाई सबैभन्दा कम मात्राको प्रयोगमा मारेको पाईयो । तर पिपलाको फलको crude extract ले अन्य extract ले भन्दा हड्डि र पाठेघर क्यान्सर कोषहरु प्रति उच्च क्यान्सर प्रतिरोध देखायो । जराको DCM extract ले मधुमेह रोगसंग सम्बन्धित α-amylase र α-glucosidase ईन्जाईम प्रति उच्च प्रतिरोध प्रदर्शन गर्यो । यसबाहेक, पिपलाको callus लाई MS तरल पोषक माध्यममा salicylic acid प्रयोग गरी culture गर्दा यसको तौल (biomass) अरुको तुलनामा बढाएको पाईयो, जबकि 100 mg/L phenylalanine तरल माध्यममा प्रयोग गर्दा सबैभन्दा बढी antioxidant activity, TPC, र TFC को मात्रा पाईयो । तसर्थ, tissue culture माध्यमबाट उत्पादित callus ले bioactive compound हरु उत्पादन गर्यो, जसले गर्दा anti-oxidant, antibacterial, anticancer र antidiabetic प्रतिक्रिया देखायो । त्यसैगरी, सतुवाको राईजोमको DCM fraction ले सबैभन्दा बढी antioxidant activity, TPC र TFC को मात्रा देखायो । यसले परिक्षण गरिएका सबै ५ प्रकारका ब्याक्टेरियाहरुको १००% बृद्धि प्रति अवरोध देखाएको छ । यसले Brine shrimp झिंगाका लार्भाहरुलाई सबैभन्दा कम मात्राको प्रयोगमा मारेको पाईयो । साथै यस extract ले अन्य extract ले भन्दा छातीका क्यान्सर कोषहरु प्रति उच्च प्रतिरोध देखायो । त्यसैगरी, राईजोमको crude extract ले मधुमेह रोगसंग सम्बन्धित α-amylase र α-glucosidase ईन्जाईम प्रति उच्च प्रतिरोध प्रदर्शन गर्यो । यसबाहेक, सतुवाको callus लाई MS तरल पोषक माध्यममा salicylic acid प्रयोग गरी culture गर्दा यसको तौल (biomass) अरुको तुलनामा बढेको पाईयो, जबकि MS media मा NAA र BAP हर्मोन प्रयोग गरी तरल माध्यममा culture गर्दा सबैभन्दा बढी antioxidant activity, TPC, र TFC को मात्रा पाईयो । तसर्थ, salicyclic acid र phenylalanine लाई callus suspension culture मा प्रयोग गर्दा secondary metabolite बढेको पाईयो । LC-HRMS प्रविधी प्रयोग गरी पिपलाको DCM fraction र callus को crude extract को रसायनिक परिक्षण गर्दा कुल २७ वटा रसायनिक यौगिकहरु पाईयो, तर सतुवाको राईजोमको DCM fraction र callus को crude extract को रसायनिक परिक्षण गर्दा कुल ३१ वटा रसायनिक यौगिकहरु पाईयो । केहि रसायनिक यौगिकहरु दुवै callus र विरुवाका in vivo भागहरु (जस्तै: जरा, राइजोम) मा पाइएको हुनाले यस अध्यनमा callus ले रसायनिक यौगिकहरु उत्पादन गरेको पाइयो ।
Contribution of crop diversity to the livelihoods of the local people in API NAMPA conservation area of Kailash Sacred Landscape, Nepal
(Institute of Science and Technology, Botany, 2022) Aryal, Kamal Prasad
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Cytogenetical Studies on Some Members of the family Asteraceae of Nepal
(Department of Botany, 2014-11) Karn(Mallick), Pushpa
Karyotypic studies of 45 taxa belonging to 33 genera in 10 tribes of the family Asteraceae are reported from Nepal. Chromosome number in somatic cells are recorded to be 2n=20 in Ageratum conyzoides and Taraxacum officinale ; 2n=18 in Ageratum houstonianum, Blumea lacera, Blumea laciniata, Dichrocephala integrifolia, Rhynchospermum verticillatum, Sonchus asper and Sonchus arvensis; 2n=32 in Artemisia indica, Blumea lacera var. glandulosa and Xanthium strumarium ; 2n=34 in Artemisia vulgaris, Cirsium arvense, Parthenium hysterophorus; 2n=36 in Artemisia abronatum, Aster ageratoids, Bidens pilosa var. minor, Chrysanthemum morifolium, Spilanthes acmella, Spilanthes calva, and Senecio laetus; 2n=28 in Anaphalis triplinervis var. triplinervis, Calendula officinalis and Gnaphalium purpureum ; 2n=16 in Crepis japonica, Erigeron annuus, Galinsoga parviflora and Ixeris Polycephala ; 2n=14 in Gnaphalium affine; 2n=22 in Blumea fistulosa, Blumea mollis, Conyza canadensis, Eclipta prostrata and Stevia rebaudiana; 2n=40 in Aster barbellatus, Aster peduncularis subsp. nepalensis and Crassocephalum crepidioides, 2n=26 in Coreopsis grandiflora and Tridax procumbens ; 2n=24 in Tagetes patula, Centaurea cyanus and Zinnia elegans ; 2n=50 in Eupatorium adenophorum and 2n=30 in Wedelia wallichii. Meiotic studies are done in floral buds of 20 species. Lowest haploid chromosome in Crepis japonica ( n=8) and highest in Crassocephalum crepidioides (n=20) are found in present study. The highest pollen stainability was found in Galinsoga parviflora (98.9 %) and lowest in Stevia rebaudiana (61.3%). Chromosome number for the four taxa Aster peduncularis subsp. nepalensis, Aster barbellatus , Artemisia indica and Senecio laetus are reported for the first time in this study. For the eleven taxa viz. Ageratum conyzoides, Ageratum houstonianum, Blumea fistulosa, Blumea lacera var. glandulosa, Cirsium arvense, Erigeron annuus, Eupatorium adenophorum, Spilanthes acmella, Spilanthes calva and Xanthium strumarium new chromosome number have been added. The chromosome counts for 41 taxa in this study are new for the flora of Nepal.
Diversity, Distribution, and Impacts of Invasive Alien Plant Species in Lake Cluster and Associated Landscape in Pokhara Valley, Central Nepal
(Institute of Science & Technology, 2022-09) Pathak, Hom Nath
Wetlands including lakes support high biodiversity providing essential ecosystem services, yet they are among the most vulnerable habitats worldwide. Several invasive alien plant species (IAPS) have invaded Nepal’s wetlands. However, the available data are insufficient to inform policy and management decisions. This research was carried out in the Lake Cluster of Pokhara Valley (LCPV), a Ramsar site in central Nepal, with the objectives to 1) analyze the diversity of naturalized plant species in the LCPV, 2) identify IAPS and their spatial distribution in Pokhara valley, 3) assess the level of eutrophication in the LCPV, 4) identify the pathways of introduction and dispersal of the IAPS, and 5) assess the impacts of IAPS on ecosystem services in the study area. Altogether 89 plots (20×5 m2) were sampled to record flowering plants and their cover along the shoreline of the nine wetlands that constitute the LCPV. The species were identified, classified based on their life forms (Raunkiaer’s life forms), and categorized into native and naturalized species. The variation of naturalized species richness with native species richness was analyzed by a generalized linear model. The relations of environmental variables with species composition were analyzed by ordination. A survey of roadside vegetation (201 5m  5m plots) was carried out to record the diversity and distribution of the IAPS in Pokhara valley. To assess the eutrophication status, altogether 89 water samples were collected from all nine lakes, and estimated nitrate nitrogen and total phosphorus. To analyze the impacts of nutrient contents on species richness and cover of native and naturalized species, multiple regression was used. To trace the sources and dispersal pathways of the IAPS, residents (n=56, age >37 yrs) living around the wetlands with a high level of plant invasions (Begnas, Phewa, and Rupa) were interviewed. To assess the impacts of IAPS on ecosystem services, household surveys (n=273), focus group discussions (n=19) and key informants’ interviews (n=23) were conducted among the beneficiaries of the LCPV such as the farmers, boaters, hoteliers, and fishermen. The study recorded a total of 258 species of flowering plants (73 families and 191 genera). The most species-rich family was Asteraceae (27 spp), followed by Poaceae (26 spp), Fabaceae (19 spp), and Cyperaceae (19 spp). Therophytes (29%) and Hemicryptophytes (27%) were the most common among the life forms. The richness of naturalized species increased with increasing native richness whereas the nutrients had no significant effect on the species richness of naturalized plants. The study found a total of 22 IAPS in Pokhara valley. Four of the recorded IAPS, viz. Chromolaena odorata, Lantana camara, Mikania micrantha, and Pontederia crassipes were among the 100 of the world’s worst invasive species. The most frequently encountered species were Bidens pilosa (63%), Ageratum houstonianum (61%), and L. camara (61%). In water samples of the LCPV, the phosphorus level was 0.29-1.25 mg/L and the nitrate nitrogen 0.04-0.17 mg/L. Based on these two nutrients, the wetlands of the LCPV were classified as eutrophic. According to the residents, most of the aquatic IAPS found in the LCPV were brought from the southern Tarai region of Nepal and northern India between the 1970s and 1990s. Among the IAPS, P. crassipes and Pistia stratiotes were brought for their ornamental values and Ipomoea carnea subsp. fistulosa was introduced for fencing purposes. It appears that Alternanthera philoxeroides was introduced accidentally to Phewa lake recently (observed for the first time in 2019). Local respondents had been familiar with Leersia hexandra for a long period (>50 years) and were not aware of the time and mode of its introduction, suggesting that this species could have the longest history of introduction to the LCPV. The study enlisted 18 ecosystem services obtained from the LCPV. The most cited services were water for irrigation, fish farming, livestock fodder, traditional mat materials (Machaerina rubiginosa), habitat protection, and natural beauty. The total economic benefit generated by the provisioning services of the LCPV in 2019 was estimated to be International $ 0.10 million per household per year. Before the proliferation of the IAPS (1989), the estimated economic value was almost triple (International $ 0.29 million per household per year). The decline in economic value was the most pronounced in fish production (International $ 151.1 thousand) and supply of lotus (International $ 24.1 thousand). The study revealed that the Ramsar enlisted wetlands of the Pokhara valley and the surrounding landscape have been invaded by several IAPS including some of the globally worst invasive species with significant negative impacts on wetland ecosystem services. As a recommendation, this study highlights science-based policy management for preventing the further spread of IAPS in the LCPV. It is suggested to prevention of the IAPS spread to non-invaded wetlands through public awareness and regular monitoring, and their control in the invaded wetlands through participatory approaches. Nonetheless, a well-managed IAPS in wetlands such as the LCPV not only supports the livelihood of the local people but also helps to meet national and global targets to conserve wetland biodiversity and habitats from further degradation.
Ecological modelling of vascular plant diversity under different climate and land use change scenarios in Nepal Himalaya
(Department of Botany, 2021) Rai, Sanjeev Kumar
The effect of climate, topography and land-use on the plant species richness and composition are widely studied topics in ecology. Recent scenarios of climate change studies also show the effect on the species diversity and gain in new area and loss in old habitats. The species richness is considerably high in Nepal with respect to its surface area due to its topography and diversity in micro climates. Climate change and land use change are affecting such richness and composition world widely. Current study was focused on assessing the species richness of vascular plants, their composition and finding the environmental variables which affect them in different elevations and land use gradients in the Nepal Himalaya. We also assessed the effect of climate change on the future distribution of Betula utilis and Larix potaninii var. himalaica which are both tree-line vascular plant species in Nepal Himalaya. The elevation of study sites ranged from 2200 m to 3800 m in six river valleys of Gorkha, Solukhumbu and Taplejung districts of Nepal. Four land use types namely crop field, meadow, exploited forest and natural forest were surveyed. Species were recorded in 25m x 2.5m plots in each land use type. We measured soil temperature as well as air humidity and temperature with data loggers on all study sites. The recorded data show a clear gradient of elevation and land use types designed in current study. Two visits were done for all plots in two different seasons. Although there are some common species recorded in both visits, the species record in individual visits are also unique. The field survey revealed a total of 840 vascular plant species belonging to 492 genera of 120 families. Among them 631 were dicots, 159 monocots, 12 gymnosperms and 38 pteridophytes. There were 96 tree species, 110 shrub species, 586 herbs and 48 climber species. Asteraceae comprised the highest number of species (85 spp.). Multivariate ordination techniques such as Detrended Correspondence Analysis (DCA) and Canonical Correspondence Analysis (CCA) were used to analyze the patterns of species composition and Generalized Linear Model (GLM) was used to find out the significant environmental variables affecting the species richness. In DCA, the first two axes were more than 4.0 standard units inferring high beta diversity. Three sets of environmental variables namely microclimate, bioclimate and topography were used for the ordination. In CCA, isothermality, minimum temperature of the coldest month, precipitation seasonality, precipitation of the coldest quarter were significant contributing bioclimatic variables. Similarly, exposition, land use types, elevation, aspect, slope, region, and valley were vi significant constraining variables for the species composition. Same set of predictor variables were used to develop three models using GLM. In addition, a synthetic model was developed by combining significant predictor variables from each set of the variables. Linear combination of mean soil temperature, mean humidity, minimum humidity, maximum temperature of warmest month, precipitation of the driest month, precipitation seasonality, valleys, land use types, elevation and latitude produce the best model in forward selection procedure. Maxent modelling was done to predict the future distribution of vascular plants under different climate change scenarios by 2050 and 2070. We chose two species namely Betula utilis and Larix potaninii var. himalaica for this purpose. Both plants occur on high Himalaya up to tree-line. Larix is a deciduous conifer which has limited distribution in central Nepal and adjoining region of Tibet, China. Betula utilis is a deciduous broad-leaved plant with wide distribution from Pakistan to China. It occurs in almost all high mountains of Nepal. The bioclimatic variables were taken from CCSM4 climate database with RCPs 2.6, 4.5, 6.0, 8.5 for 2050 and 2070. Additionally, elevation, aspect and land use types were taken as predictor variables which were taken from the land cover map of Nepal 2010. All models were validated with various statistical tests. All models showed AUC > 0.9, accuracy between 88.4875 and 95.2858, error rate between 0.1151 and 0.0471, and TSS between 0.6359 and 0.7613. The validation parameters showed the robustness of the models. The elevation and annual mean precipitation were main contributing factors for the distribution of Betula utilis and Larix potaninii var. himalaica respectively. The distribution area of Betula utilis will decrease by -18.72% under RCP 2.6 but will increase in all other scenarios by 2050 and 2070. The new gains in area will be distributed towards the western mountains at all RCPs in 2050 and 2070. The predicted area of Larix potaninii var. himalaica did not show specific trend of increment or decrease at all RCPs by 2050 and 2070. The findings of the current study will be applicable in the assessment of effect of environmental and land use variables on the species composition and richness other group of plants too. Current study will be also helpful in devising future policies of conservation of rare, vulnerable, and threatened plant species whose distributions are more likely to be affected by the climate change in the future. Key words: Biodiversity, SDM, Species composition, Species distribution, Treeline
Ecology and impact of an invasive weed Ageratina Adnophora in central Nepal
(Institute of Science and Technology, Botany, 2021) Poudel, Anju Sharma
Invasive alien species (IAS) have been increasing at an alarming rate all around the globe with significant negative impacts on the environment, ecosystem services, human health and socio-economy. Therefore, understanding the ecological features of IAS invasion mechanisms, potential shift in climatically suitable regions of IAS under future climate change scenarios, and factors influencing abundance of their biological control agents is an urgent need to better inform the management policies and practices. In this study, ecological features such as distribution (current and future), functional traits variation along the elevation gradient, ecological impacts, and influence of abiotic factor (elevation) on the abundance of a biocontrol agent of a noxious invasive weed Ageratina adenophora (Sprengel) R. King & H. Robinson were analyzed in central Nepal. Maxent model was used to predict the suitable areas of A. adenophora in Chitwan Annapurna Landscape (CHAL), Nepal under current and three future climate change trajectories based on three representative concentration pathways (RCPs 2.6, 4.5 and 8.5) in two different time periods (2050 and 2070) using occurrence data of the species in the study region, climatic variables, and topographic features. To analyze the change in area invaded by A. adenophora from the year 1990-2018 in CHAL, Landsat images were used and knowledge-based image classification technique of remote sensing was applied assigning seven rules (elevation, landuse, Normalised Difference Vegetation Index (NDVI), digital number, maximum temperature, minimum temperature and rainfall). Furthermore, spatial distribution of A. adenophora was assessed in small area of interests viz. Mahadevbesi (Dhading district), Sarangkot (Kaski district) and Ghasikuwa (Tanahun district) using both low spatial and spectral resolution (Landsat) and high spatial and spectral resolution (Worldview-2) images to find out the more accurate multispectral sensors. Six functional traits namely Specific leaf area (SLA), Leaf nitrogen content (LNC), number of floral heads per ramet, total seeds per floral head, seed size and seed mass of A. adenophora were taken into consideration for analyzing their variation along the elevation gradient of 240 2965 m asl in central Nepal. Changes in species richness, species diversity, species composition and soil chemical characteristics (Organic carbon, Total nitrogen, phosphorus and potassium) due to A. adenophora invasion was studied at two sites (Chandragiri and Simbhanjyang) in Middle Mountain region. Role of elevation on the abundance of a biocontrol agent, i.e., Procecidochares utilis Stone and on size of gall formed by this gall fly was explored. Furthermore, the effect of this agent on the stem diameter of the weed, and the capacity of the gall to act as nutrient sink was further analysed. Minimum temperature in the coldest month (bio 6) was the most important variable affecting the distribution of A. adenophora. About 38% of the CHAL area is currently climatically suitable for the weed, Middle Mountain being the most suitable one. A vii predicted increase in suitable area under future climate scenarios ranged from 1-2 % from the current suitable areas. All protected areas and three physiographic regions (Siwaliks, High Mountains and High Himalaya) are likely to gain climatically suitable areas in future climate scenarios. The upper elevational distribution limit of the weed is expected to expand by 31-48 m in future climate scenarios. The area invaded by A. adeophora increased from 0.22% in 1990 to 4.55 % in 2018. Multispectral sensors, i.e., Worldview-2 images had higher accuracy in comparison to Landsat images and provided a better scenario of species distribution. SLA, LNC, number of floral heads per ramet and total seeds per floral head decreased with the increasing elevation along the elevation gradient of 500 2500 m asl. However, different trend in functional traits was observed along elevation gradient of 1500-2530 m asl. Seed size and seed mass increased with the increasing elevation at all sites along the elevation gradients. A trade-off was noticed between seed size and seed number indicating the strategy of the weed to adapt to low temperatures at high elevations. Ageratina adenophora reduced the species richness as well as species diversity in the invaded sites. Shannons diversity index in non-invaded plots was 1.9 times higher than in invaded plots. Similarly, diversity index in non-invaded plots was 1.6 times higher than in invaded plots. Invasion by A. adenophora also caused significant change in species composition. difference in species composition between invaded and noninvaded plots. Furthermore, A. adenophora invasion increased the carbon and nitrogen content in the invaded plots. However, A. adenophora invasion had no effect on phosphorus and potassium concentration. Site-specific variation in the impact of A. adenophora was noticed. Elevation had a significant effect on the gall abundance as well as gall size. Both gall abundance and size peaked at mid elevation (1950-2000 m asl). Stem galling by the fly reduced the stem diameter of the weed and all the three nutrients (N, P and K) were higher in galls than in ungalled stems. This study indicates that the elevation is an important abiotic factor that influences the P. utilis stem gall abundance and gall size. Furthermore, the galls formed by P. utilis act as nutrient sinks. In conclusion, probability of range expansion and upslope movement as revealed by niche models and functional trait studies suggests for a need to prevent further spread of the weed in the study area. Significant negative impact on plant community and soil chemical characteristics reported in this study also emphasizes for a prompt action and management interventions to be adopted by scientific community and resource managers. As the study revealed that insect gall abundance is affected by elevation and peaks at mid-elevation range, this knowledge on gall dynamics is central to the successful management of the weed through the use of biological control agents. Keywords: Invasive species, Distribution, Functional traits, Impact, Biocontrol
Ecology and Phytochemistry of Zanthoxylum armatum DC.
(Faculty of Botany, 2022) Phuyal, Nirmala
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Ecology of Some Weeds of Winter Crop Fields in Kathmandu Valley
(Department of Botany, 2021) Das Mallik, Baby Babita
In Nepal, weeds cause yield loss up to 45% in the mustard (Brassica campestris L.) field and 50% in wheat (Triticum aestivum L.), sometimes even more losses when the weed population and density are higher. Usually, weeds are harmful but some may have economic importance as organic compost, food or fodder, medicine, and industrial uses. The use of invasive plants (like Ageratina adenophora (Spreng) King & Rob. and Parthenium hysterophorus L.) and a native weed (Artemisia dubia Wall. Ex. Besser), for preparing biofertilizer and their effect on weed and winter crops have been investigated in the present study. The main objectives of the present study were to understand the weed ecology in winter crop fields. Other important objectives were to investigate the allelopathic effect of Artemesia dubia, Ageratina adenophora and Parthenium hysterophorus to control selected weeds of winter crops by using aqueous extract, compost extract, and their compost. The study was carried out at the wheat and mustard fields of selected sites (Kirtipur, Bhaktapur, Godawari, Chapagaon, Dharamsthali, and Shivapuri) during winter (Oct-March) in the year 2012-2014. Based on the highest IVI value only four common weed species (Ageratum conyzoides L., Bidens pilosa L., Cyperus rotundus L., and Galinsoga parviflora Cav.) were selected for a further ecological studies like phenology, soil seed bank, seed morphology, seed germination, and allelopathic effect. Altogether 40 plants of each weed (Ageratum conyzoides, Bidens pilosa, Cyperus rotundus, and Galinsoga parviflora) were randomly selected and their phenophase was carefully examined from the germination stage to seed dispersal stage of plants using the phenological index technique. The shape, color, and size (length and breadth) of the four common weed seeds were measured under a compound microscope for weed seed morphology study. Seed germination experiment was conducted on environmental conditions like moisture (content 3, 6, 9, 12, 15 ml), temperature (5, 10, 15, 20 and 25˚C), pH (value 4, 5, 6, 7, 8 and 9) and light (normal, red, yellow, blue, green and dark color). For the crops, optimum moisture content (9 ml) was required. The experiments on seed germination of moisture indicated that Cyperus rotundus and Galinsoga parviflora do not require more moisture to germinate and grow. Seed germination of both crops enhanced significantly at 15 to 20˚C treatments but all weed seeds were significantly high at 10 to 15˚C. The percentage of seed germination of both crops Brassica campestris and Triticum aestivum increased significantly in normal and green light. Seed germination of Ageratum conyzoides, Cyperus rotundus, and Galinsoga parviflora was significantly different in normal, red, yellow, and green light. Germination of all weed seeds was completely inhibited in blue and dark light. Seed germination and seedling growth were higher in pH 5-7 in most cases. Seed germination was also conducted with different concentrations (control, 1, 2.5, 5, 10%) of chemical fertilizer solutions and different doses of fertilizer amended in soil (control, 10, 20, 40, 50 g/kg soil). Seed germination of both crops and all the weeds were mostly high in control and 1% of both urea and potash solution. The germination of selected weed seeds reduced significantly with increasing concentrations of both urea and potash in soil. The aqueous extracts vegetative parts of Ageratina adenophora, Parthenium hysterophorus, and Artemisia dubia, their compost extract (of the whole plant) of different concentration (control, 1, 2.5, 5, and 10%) and soil amended with composts (of different doses 0, 10, 20, 40, and 50 g compost/kg soil) were used to understand their effects on seed germination, seedling growth of crops (Triticum aestivum, Brassica campestris) and the common weed. The aqueous and compost extracts of Ageratina adenophora and Parthenium hysterophorus significantly reduced seed germination and seedling length (shoot and root) with increasing concentrations. The stem and leaf extracts of Ageratina adenophora showed a more inhibitory effect on the seed germination of both winter crops and all weeds as compared to root extract. In the soil amended with different amounts of Ageratina adenophora and Parthenium hysterophorus compost showed more reduction in seed germination among the weeds in comparison to both crop plants. Seed germination of Cyperus rotundus was completely inhibited even at 1% Parthenium compost extract and soil amended with 10 g/kg Parthenium compost. The aqueous extract and compost extracts and compost of the native plant Artemisia also significantly reduced seed germination, seedling length of both selected crops and weeds, with increasing concentrations, but were less detrimental than the compost of the other two invasive weeds. From this study, it was found that compost of Ageratina adenophora and Parthenium hystrophorus at the rate of 20-40 g/kg soil was effective to control the winter weeds. Hence the use of Ageratina adenophora and Parthenium hysterophorus compost are suggested to use at low concentrations (20-40 g/kg soil) in wheat or mustard fields, especially to control most of the common weeds. This information suggests preparing compost from the invasive weeds which can act as environmentally safe and cost-effective bio-herbicides along with an important strategy for weed management.
Ecophysiology of Spirodela Polyrhiza (L.) Schleiden (Greater Duckweed)
(Faculty of Botany, 2019) Pokharel (Bhattarai), Bindu
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Ethnobotany and Antibacterial Activities of Selected Medicinal Plants of Nepal Himalaya
(Department of Botany, 2009) Bhattarai, Shandesh
This study aims to explore medicinal plants from Manang and Mustang districts and examine their antibacterial activity in vitro against different strains of microorganisms. Field information was gathered by direct observation of locals through semi-structured interviews and information regarding the bioassay test was obtained through laboratory research. A total of 157 ethnomedicinal plant species belonging to 56 families and 114 genera are reported from the study area. These 157 locally used medicinal plants treat 150 ailments. This study found that many different parts of medicinal plant species are used as medicine. It would follow that the most commonly used plant parts have been selected because they contain more active principles in the form of biologically active secondary metabolites in comparison to the least commonly used parts. Of 157 medicinal plants documented, 88 plants were used for multiple uses, such as for food, fence and fuelwood, ritual and religious, and others. Several medicinal plants, i.e., Allium species, Hippophae species, etc., with multiple uses have great medicinal value and high market price even in Kathmandu and Pokhara. Even though the market price of these species has been increasing steadily, the local consumption has not yet decreased. Therefore further bioprospecting research on these species could help with the conservation and management of these local resources as well perhaps benefits the local people economically. In vitro antibacterial assays of 92 extracts from 79 ethnomedicinal plants used to treat diseases potentially caused by bacteria were examined. Overall, 73 % of plant extracts showed activity against Gram-positive Staphylococcus aureus, and Bacillus subtilis, and 69 % showed activity against Gram-negative Escherichia coli, and Pseudomonas aeruginosa. Although the nature and number of active antibacterial principles involved in each extracts are not clear, the broad spectrum of activity of several plants is promising. Thirty-three selected plant species were extracted with methanol, dichloromethane and hexane, resulting in a crude separation of the chemical components into groups of varying polarity. The minimum inhibitory concentration (MIC) of these extracts against the same bacterial species was obtained, and gives insight into the chemical nature of the biologically active constituents. The strong activity of the highly non-polar hexane extracts (shown by the low MIC values) indicates that the bioactive chemical(s) of those plant species was best extracted in non-polar solvent, and therefore was likely to be non-polar as well. Altogether 39 medicinal plants were prioritized and categorised as high, moderate or low priority in Manang and Mustang districts. Among the 39 prioritized species selected, 8 species were high priority, 29 were moderate priority, and 7 species were low priority. Bulk amounts of medicinal plant trade is seen from Manang and Mustang and if the process of trading of important medicinal plants continues on this scale for several years, species such as Cordyceps sinensis, Dactylorhiza hatagirea, etc, will become increasingly rare. Therefore I suggest immediate steps of cultivation of these species in the barren lands and use of sustainable harvesting approaches which may be helpful to conserve these species as well as othere wild plant resources in their natural habitats. In conclusion, this survey has shown that the local populations of Manang and Mustang districts have a wide knowledge on the use of wild plants for various purposes, including medicinal, food, fuelwood, fence, fodder, timber, household article, ritual, religious, etc. The present laboratory work lends support to the claims by traditional medicinal healers regarding the biological usefulness of the above plants. The antibacterial activities of the plants often explain their use by the local community
Ethnobotany and Antimicrobial Study of Selected Medicinal Plants Used by Magar Community in Nawalpur District, Nepal
(Institute of Science and Technology, 2022) Nemkul, Chandra Mohini
Field survey and ethnobotanical data was collected from 2015 to 2017 in Hupsekot , Bulingtar rural municipalities and Kawasoti urban municipality of Gandaki province, Nawalpur district, Nepal focusing on Magar community. To verify traditional use of selected plant species for diarrhea, urinary tract infection, typhoid and pneumonia, laboratory tests of the extracts of the plants were performed. Methods: Data were collected by interviewing local healers and knowledgeable people. Plants were selected for laboratory tests on the basis of factor for informant consensus (FIC) and feudality level (Fl) along with use mention (UM). Plant parts dried at room temperature were used for extraction by using hexane and 70% methanol successively. The extracts in amount 50µl were used for in vitro antimicrobial tests by agar well diffusion method. Dimethoxy sulfate (DMSO) was used as negative control; ampicillin and gentamicin were used as positive control. The test bacteria were Pseudomonas aeruginosa, Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, Enterococcus faecalis, Bacillus subtilis, Shigella dysenteriae and Salmonella enterica subsp. enterica serovar typhi. Phytochemical screening was performed by colorimetric method. The effective compounds present were analyzed by GC-MS analysis. Estimation of total phenolic content was done using the Folin-Ciocalteu colorimetric method. Antioxidant assays were done by DPPH free radical scavenging and H2 vi O2 scavenging methods. Results: Among 160 plant species recorded 124 species were medicinal use. Phanera vahlii, Flemingia strobilifera, Lagerstroemia parviflora, Stephania glandulifera, Tectaria coadunata, Woodfordia fruticosa, Rhododendron arboreum and Rhus chinensis were selected for gastrointestinal category; Tinospiora sinensis, Cissampelos pareira and. Azadirachta indica for urinary tract infection (UTI) category; Antidesma acidum and Aegle marmelos for the respiratory category; Callicarpa macrophylla for typhoid. Alkaloids, anthocyanosides, flavonoids, saponins, steroids, terpenoids, tannin and polyphenols were detected in the extracts. Gas chromatography and mass spectrometry (GC-MS) analysis showed that antimicrobial compounds such as 2-Methoxy-4-vinylphenol, 5(Hydroxymethyl)-2-furancarbaldehyde, Phytol, 3,5-dihydroxy-6-methyl-2,3-dihydro-4Hpyran-4-one, Stigmasterol, 1,2-Benzenedicarboxylic acid, disooctyl estser, vitamin E and squalene were present in the extracts. Methanolic extract of Rhus chinensis (RCM) showed largest zone of inhibition (ZOI) (23±0.57mm) against Escherichi coli followed by Woodfordia fruticosa (18mm) (WFM). The lowest value of minimum inhibition concentration (MIC) against Escherichia coli was <1.56mg/mL (WFM). RCM and FSM showed antimicrobial activities against Shigella dysenteriae causal bacteria of dysentery but MIC values of them were bacteriostatic.WFM (18.66±0.66mm) showed the largest ZOI against Enterococcus faecalis. The lowest value of MIC was 3.12mg/mL (WFM) against Enterococcus faecalis and it was bactericidal. WFM showed the largest ZOI against Pseudomonas aeruginosa. The lowest value of MIC against Pseudomonas aeruginosa was <1.56 mg/mL (WFM). RCM (14.66±0.33mg/mL) showed larger ZOI against Klebsiella pneumoniae and followed by WFM (13.5±0.67mg/mL) and methanolic extract of Flemingia strobilifera (FSM) (11.66mg/mL). The lowest MIC value was 6.25mg/mL of FSM against Klesiella pneumoniae and it was bactericidal. The result showed that MIC value of methanolic extract of Antidesma acidum (AAM) (12.5mg/ml) against Klebsiella pneumoniae was bacterididal. MIC of methanolic extract of Callicarpa macrophylla leaf (CMML) was 25mg/mL against Salmonella typhi. MIC value of CMML against Salmonella typhi was bactericidal. RCH (hexane extract of Rhus chinensis) (16±0.33mm) showed larger ZOI against Escherichia coli. MIC of RCH was 1.56mg/mL against Escherichia coli was bacteriostatic and kill the bacteria at 6.25mg/mL. Total phenol content (TPC) in the plant extracts had significant variation ranging from 8.15 to 336.95 mg of GAE/g of dry extract. FSM contained maximum amount of TPC (336.95±14.61 mg of GAE/g of dry extract). 2, 2-Diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging range from 4 to 94% at 100 µg/mL concentration of the 70% methanolic extracts and 50% inhibition concentration (IC50 vii ) range from 21.59±0.26 to 1434.11±1.17 µg/mL. The best DPPH free radical scavenger was methanolic extract of Rhododendron arboreum. The methanolic extract of Woodfordia fruticosa was the best H2 O2 scavenger. Conclusion: The extracts of the plants used for diarrhea by Magars of the study area, have shown antimicrobial activity against Escherichia coli, diarrhea causing bacteria. The most effective against Escherichia coli was the extract of Woodfordia fruticosa. The extract of the plant used for UTI by magars, have shown moderate effect against UTI causing bacteria. The result also verify local us of Callicarpa macrophylla against typhoid. These plants also have DPPHradical and H2 O2 scavenging properties. Woodfordia fruticosa, Flemingia strobilifera and Phanera vahlii could be used for treatment of UTI along with local use of Tinospora sinensis, Cissampelos pareira and. Azadirachta indica. In-vitro animal tests are required for these.
Floral Species Richness Pattern in Arghakhanchi and Adjoining Areas, Nepal
(Institute of Science & Technology, 2023-12) Nepali, Baburam
The biodiversity and their pattern may vary from a broad geographic area to a small local scale due to changes in their linked components along spatial and temporal gradients. Basic knowledge of distribution, diversity, and roles is necessary for the conservation of any group of organisms. In this synthesis I examined the variations in species composition and richness patterns over various spatial gradients and how they relate to the nutrients found in the low mountainous regions of west Nepal. This thesis is based on field-survey data of vascular and lichen species, analyzed soil data as well as secondary data from published articles. The study is mainly focused on vascular plant as well as lichen species composition, richness and soil heterogeneity, which is based on direct field sampling in national and community forest of Arghakhanchi and adjoining area: Resunga forest of Gulmi district, Nepal, to compile baseline information. The survey was done in autumn and spring seasons for two consecutive years (2018-2019) at various elevations that varied from 200 to 2300 m. The primary data of vascular plants was collected by use of 10 X 10 m quadrats in stratified random sampling design along the elevational gradient. From the same sampled plots, lichen specimens and soil samples were also collected. The soil samples were chemically analyzed in laboratory. The vascular and lichen specimens were identified by comparing with already identified herbarium specimens and by following identification keys. The data was analyzed by use of various statistical techniques: Generalized linear model (GLM) regression, PerManova, DCA and CCA ordinations in R software. The elevational diversity indices (Shannon-Wiener, Simpson and Pielou’s evenness) of plant life forms were estimated. A total of 606 species of vascular plants and 47 species of lichens were found in the field. Plant life forms classified by Raunkiaer (1934) yielded the following results: 265, 37, 158, 57, and 89 species for Phanerophytes, Chamaephytes, Hemicryptophytes, Geophytes, and Therophytes, respectively. According to the different types of forests, the mixed pine forest containing Schima wallichii, Castanopsis indica, Pinus roxburghii obtained the highest vascular species richness. Capillipedium assimile is the species which obtained bear the highest Important Value Index in all three ecological regions (Tropical, Sub-tropical and Temperate). The regression results show that all vascular plants, life-forms species and lichen species follow the statistically significant elevation-dependent unimodal structure. Unimodal pattern is found as common elevational species richness pattern, but is not compulsory pattern against elevation in small areas. The explanatory factors show a stronger influence on species composition than species richness, according to correlations and canonical correlations. The Hemicryptophytes, Phanerophytes and Therophytes had significant positive relationships with elevation and soil nitrogen, whereas the Chamaephytes, and Geophytes, had a negative relationship. Elevation and nitrogen function show the uniqueness of the interplay between life forms by acting as key factors of plant dispersal. Other factors-RRI, soil pH, phosphorus, potassium show comparatively less impact in species composition. According to the appearance of a peak in species diversity at nearly the same elevation and a pattern that is similar, the diversity of vascular plants promotes the abundance of lichens. The diversity of lichens was strongly correlated with the habitat and elevation than the aspect of hills. At all levels of spatio-temporal gradients, species richness and composition patterns are strongly scale dependent. Certain variables, such as soil-related local-scale heterogeneity and slope aspect, are essential for figuring out species composition and richness trends. Based on our results, it is cleared that the study area: Arghakhanchi district and its adjoining areas provide variable habitats for vascular as well as lichen community. Open ground floor is mainly rich in native as well as alien herb plant species, which are less dominant in forests. It is clear that species composition is a more useful tool in landscape ecology and biogeography research than species richness. Therefore, plant community structure should be used as a reliable and insightful indicator in biogeography studies and conservation planning.
In vitro mass propagation and production of bioactive metabolites from Valeriana jatamansi Jones and Tinospora cordifolia (Wild.) Hook.F. & Thoms
(Institute of Science & Technology, 2023-08) Pandey, Sushma
Valeriana jatamansi Jones (Sugandhawal) is a perennial herb, belonging to the Caprifoliaceae family known for its medicinal and ethnobotanical values. The species is threatened in its natural habitats as its rhizomes and roots are used for the production of medicines in the herbal and pharmaceutical industries due to the presence of valepotriates. Similarly, Tinospora cordifolia (Wild.) Hook. f. & Thoms. (Gurjo) is a climbing shrub belonging to the Menispermaceace family and has been shown to have a variety of ethnomedicinal, pharmacological and medicinal activities. T. cordifolia is also one of the most commercially used plants in pharmacy. The phytochemical and pharmacological properties of these two species have been extensively studied worldwide. However, in the context of Nepal, they are yet to be explored. In the case of V. jatamansi Jones, research has been carried out to optimize an efficient plant tissue culture system for mass propagation. The nodal segments taken from the in vitro plants developed on BAP (2 mg/L) with different PGRs at different concentrations and 10% coconut water produced the maximum shoot length (6 cm), shoot number (13.1), root length (7.5 cm), and root number (19.6). RAPD and ISSR markers were used to confirm the genetic integrity of the in vitro plants, acclimatised plants and wild plants. The effects of sodium nitroprusside (SNP), a nitric oxide (NO) donor, and various growth regulators on callus induction and shoot organogenesis of V. jatamansi were investigated. 1.5 mg/L of 1-Naphthaleneacetic acid (NAA)+15 µM SNP induced the highest callus frequency (91.18%). Maximum in vitro shoot multiplication was observed with 10% CW+15 μM SNP (89.32%). In addition, IAA, IBA, NAA and the elicitors methyl jasmonate (MeJA) and salicylic acid were added to adventitious root cultures of V. jatamansi Jones to analyse the production and growth kinetics (SA). Among the plant growth regulators studied, NAA (2.0 mg/L) induced maximum biomass (PGRs). MeJA, increased the biomass of the root cultures as compared to SA. Root cultures were analysed for their phytoconstituents and antioxidant potential. Methanolic in vitro extracts of the roots of V. jatamansi in NAA (2 mg/L) gave the highest content of phenols (55±1.00 mg GAE/g), flavonoids (219±1.00 mg QE/g) and DPPH activity (84.33±0.577%) as compared to the wild plants. Compared to NAA, the elicitor MeJA produced more biomass but less phytoconstituents. SA did not produce significant biomass. The GC-MS analysis showed that the roots treated with NAA accumulated 50 bioactive compounds, similar to the roots of the wild plants, which contained 48 compounds. Valepotriates such as valeric anhydride, valeric acid, and derivatives were found in areas of the treated roots that had higher concentrations than those of the wild plants. The MeJA-treated cultures accumulated 21 compounds while the SA elicitation accumulated 23 compounds, including derivatives of valeric acid. The examination of gene expression using the sesquiterpene synthase genes revealed that the TPS2 gene expression was significantly higher in both samples (more than five fold increase) while TPS5 had the highest gene expression (16 fold) and TPS6 had a four-fold increase in the NAA treated in vitro root cultures compared to the in vivo root cultures. In T. cordifolia, the explants of nodal segments were first treated in MS with different doses of BAP and/or KIN, with MS+BAP (2.0 mg/L) and the nodal segments were treated with various concentrations of BAP, BAP+KIN, and coconut water for proliferation of which, 5 mg/L induced significant shoot induction (9.0 shoots per explant), and mean shoot length (8.0 cm). Nodal segments proliferation increased when the media were supplemented with nodal segments at 5% and 10%. However, the addition of MS BAP (5mg/L)+10% coconut water induced maximum response with shoot number (24.0) and mean shoot length (12 cm). The genetic fidelity of these plants was also confirmed by RAPD and ISSR marker analyses in wild and in vitro cultures. Total phenolic content (TPC) was highest in wild stem followed by in vitro plant extract and wild leaves. The TFC content, and antioxidant potential were highest in wild stems followed by the wild leaves and the in vitro plant. (TPC; wild stem 128.55±0.491 mg/g, in vitro plant 107.33±0.985, wild leaves 105.6847±1.060) (TFC wild stem; 83.61±0.2773 mg/g, in vitro plant 58.034±0.148, wild leaves 62.50±0.329). Antioxidant activity; wild stem with (IC50 193.229±0.013), in vitro plant with (IC50 219.83±0.468), wild leaves with (IC50 204.386±0.165). GC-MS Analysis of the wild stem revealed the presence of 40 compounds and 31 compounds in the in vitro plant detecting various bioactive compounds including palmitic acid. In the present study mass propagation through in vitro cultures of V. jatamansi and T. cordifolia, and phytochemical screening of both V. jatamansi and T. cordifolia were standardised which is the first of its kind with respect to these species in Nepal. Root cultures establishment, characterization of valepotriates in adventitious root cultures of V. jatamansi and expression of the sesquiterpene synthase gene was successfully developed
In vitro Morphogenesis of Asparagus racemosus Willd. and Rauvolfia serpentina (L.) Benth. ex Kurz.
(Faculty of Botany, 2011) Pant, Krishna Kumar
Asparagus racemosus willd. and Rauvolfia serpentina Benth. Ex. Kurz. Belonging to the families Lilliaceae and A pocynaceae respectively are among the most important natural resources of Nepal. Both these plants have high medicinal value and are decreasing from thenatural forests due to unsustainable collection and destruction of their habitats forvarious reasons.R. serpentinais listed in the “Appendix II” of the CITES and is under the category “E”of IUCN. Similarly,A. race mosusis facing towards its extinction due to its increasing demand in the local as well as international markets. Understanding these facts, the GoN has prioratised these species for research in the areas of multiplication and cultivation. Considering these facts,the present research was undertaken to support the national mission of conservation through ex-situ way. Plant tissue culture method was selected because it is one of the promising methods of rapid plant propagation in short time and less space without damaging the mother stock.From the present work,most effective explant for the rapid multiplication of these plant species usingtissue culture technique has been identified to be the nodes. Calli induced from the no desaresuitable for organogenes is as well as somatic embryogenesis. Induction of buds from the shootsin A. racemosusis another potential area where more works are necessary. In the overall experiments, NAA was found to be the most effective hormone among the auxins in all respects and BAP among the cytokinins tested. From the seed germination experiments of Asparagus racemosuson MS basal medium asingle seed produced up to 13 shoots.In the tissue culture experiments, the nodes produced morecallus when cultured on the medium containing NAA alone in higher concentrations or when combined with BAP. The tough friable calliinduced from the nodes on high auxin containing media were capable of inducing somatic embryoids. Generally, high auxin either singally or incombination with higher concentration of cytokinin produced large number of somaticembryoids from the calli. Shoot formation from the calli was supported by lower cytokininwhereas root induction by higher cytokinin levels in the media.In case of multiple shootinduction either a combination of low NAA (0.1 mg/l) and high Kn (1.0 or 2.0 mg/l)concentration or various combinations of IBA and BAP in the MS medium were promising.Similarly, for the root induction, NAA at low concentration (0.1 mg/l) was found to be the bestalthough its other higher concentrations also induced roots at significant levels. Agar vii manipulation experiment for the induction of storage roots produced insignificant result. Apreliminary study on bud induction from the shoots has shown very interesting results. This can be an alternative method of rapid multiplication of plants. Vitrification of shoots is one of the major problems in tissue culture and generally the vitrified shoots are discarded. We here, have used the vitrified shoots as explants and produced normal shoots using very low amount of cytokinin or auxin in the sub-culture medium.Sand rooting using NAA 100 mg/l pulse treatment, acclimatizing in a shade house on the coco-peat and transferring the acclimatized plantlets on the gaden soil in an open environment were the final steps.Another important andthreatened medicinal plant Rauvolfia serpentina also was taken for the present research. Here,callus induction from the shoot and leaf explants were supported by the incorporation of 2,4-D or NAA above 1.0 mg/l and 0.5 mg/l singally in the MS medium respectively. Incombination of auxin and cytokinin,NAA 1.0 mg/lalong with all concentrations of BAP yielded highly significant amount of callus especially from the shoots. The calli obtained from the leaf wererarely embryogenic as well as caulogenic. The shoot induced friable green calli were able to go for organogenesis as well as somatic embry ogenesis. The multiple shoot induction was generally supported by a lower auxin and higher cytokinin concentrations. The maximum induction was observed on the MS medium incorporated with IBA 0.1 + BAP 2.0 mg/l with 7.83±1.01 shootsper explant. For the induction of roots from the shoots, NAA singly at almost all concentrations were found to be significant, however NAA o.5 mg/l induced the maximum average roots upto12.50 per explants after 12 weeks of culture. IAA and IBA did induce some roots when alone but in combination with cytokinins their performances were very poor. Finally, the shoots rooted both in vitroandin vivo after pulse treatment with 100 mg/l auxin survived in the open environment after acclimatization in the shade house.
Mass propagation and ex-Situ conservation of cymbidium aloifolium (L.) Sw., A threatened medicinal Orchid of Nepal through artificial seed technology
(Institute of Science and Technology, Botany, 2017) Pradhan, Shreeti
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Mushroom Diversity in Central Nepal: An Ethnomycological Approach
(Department of Botany, 2008) Pandey, Nina
Nepal is a multi lingual, multi religion and multi ethnic country. The country is rich in biodiversity due to topographic and climatic variation. The ethnic groups in Nepal are distributed within all the 75 districts of the country. The main Mycophagus groups in the study area are Tamang, Gurung, Sherpa, Lama, Chepang, Danuwar, Tharu, Rai, Limbu, Newar etc. Mycodiversity is the branch of biodiversity, which reflects the fungi diversity. Larger fungi of the divisions Ascomycotina and Basidiomycotina are called mushrooms. Edible species are called “Mushroom” and “Poisonous” ones as “Toadstools” (Pacioni 1985). In Nepal, mushroom collection and consumption have been on-going since time immemorial by different ethnic groups The mycological collections from Nepal started with the works of Lloyd (1808) (with one Ganoderma species) and Berkeley (1838) (with one Polystictus species).Since then, J.D. Hooker in (1848-1854), gathered many fungal species during his botanical expedition to eastern Nepal.His collections were studied and reported by Berkeley (1854). There- after, many Nepalese and foreign mycologists have contributed in this field. In the initial stages of research on mycological specimens in Nepal, there were no specific intentions of ethno mycological investigations. However, mushrooms were collected and reported as edible or non edible according to human uses (Singh 1966, 1973, 1974; Adhikari 1976). Ethno mycological studies and Ethno botanical studies including mycological species were later undertaken by several workers with regard to those consumed by selected ethnic tribes or those used by people in selected geographic areas in Nepal. The present research aims to enumerate and document wild Mushrooms, conduct chemical analysis of some important mushrooms, explore ethno mycological knowledge of local people, and thereby provide recommendations. Central Development Region of Nepal is the main Study Area of the thesis. The study was limited to Langtang National Park (Dhunche to Kyanginj ghumpa), Kathmandu Valley including adjoining areas(Sunadrijal, DhuliKhel, Surya-binayak, Champadevi, Nagarjun, Matatirtha e.t.c ) and Chitwan (Tikauli Samudayik Ban, Amrit Dharapani Samudayik Ban). The collection of mushrooms started from the year 2001 to 2005 mainly during the months of May, June, July, August, September and October. During the collection of samples, geographical information of area i.e. Latitude, Longitude, XVII Altitude, Soil-type, Forest type, Habitat, Climate, Temperature along with Date, Collection Number and Place of Collection were recorded. The field work was conducted from July 2001 to August 2005 at different areas of Central Nepal. While conducting field trips in various sites, a professional mushroom hunter and some other friends were accompanied. The mushrooms were photographed in their natural habitat before they were collected. Broken, rotten and insect- eaten species were discarded and only mushrooms with healthy basidiocarps were picked up. All morphological characters were recorded. Spore prints were obtained. Each specimen of same species or different species collected from the same locality or different localities were cleaned up with the help of the brush. They were placed in separate wax- paper bags so as to prevent mixture of spores. Bamboo baskets and paper bags were used for the collection of specimens in the field. The specimens were preserved in dry condition through blotting the water by different means (sun dry, placing near fire place etc.) - knowing that ‘The dried preserved samples only can be utilized for microscopic study and for chemical analysis, while the liquid preserved samples can be used only for museum specimen’. The specimens were brought to the laboratory for the microscopic studies. The specimens were identified with the help of standard literatures. After identification, they were filed and stored each with a Label tag. Napthalene balls and Para-dichlorobenzene were used as insect repellents in the storage cabinet. The cabinet was kept in dry, well aerated and sunny room. SEM (Scanning Electron Microscopy) was done to the closely related species at IIT (Indian Institute of Technology), New Delhi for spore ornamentation. This technique helps for proper identification of the particular species. The ethnomycological information were collected by Participatory Rural Appraisal (PRA) and Rapid Rural Appraisal (RRA). For the chemical analysis of Mushroom, determination of moisture, ash, acid insoluble ash, as well as minerals like Calcium, Phosphorus and Iron were done in the Department of Food Technology and Quality Control in accordance with AOAC (1995). Carbohydrate determination was done only of ‘reducing sugar’ through the Fehling’s test. The Quantitative estimation of total free amino acid content in mushrooms was found using the Ninhydrin Reaction (Colorimetric method). Qualitative determination of amino acids in Mushroom was done by ‘ascending paper chromatography’. Quantitative Determination of Crude Protein was done by Micro – Kjeldahl's Method. Determination of soluble protein of mushroom was done by Bradford’s Method. These analysis were performed in Central Department of Microbiology,TU. Determination of Protein profile by SDS-PAGE was performed in RLABB (Research Laboratory for Agriculture Biotechnology and biochemistry). XVIII In the present study, 575 species belonging to 54 families and 82 genera have been identified, of which 251 and 324 samples were identified up-to genus and species level respectively. Similarly, in the present study, 50 ethnomycologically important species have been enumerated and through the same 25 recorded species are added in the mycoflora of the country. Among the identified species, 10 species are added in the list of edible species of the country. According to literature review, this research has increased the list of edible mushrooms in Nepal to 181. Significantly, ethno mycological study has mainly been focused on Tamang and Chepang, as they are the traditional mycophilic groups besides others. Here, some useful descriptions including ‘five reasons for the forbiddance of use of mushrooms by Brahmins, different uses of mushrooms , ethnic and modern mushroom recipes , methods to minimize mushroom poisonings etc.’ have been made. The present study has found out that no poisoning and mortality cases were found in high altitude as well as in Terai region (study area): the reason behind this being the locals’ ability to identify the edible mushrooms from the poisonous ones. Further, it was found out that the highly prized wild edible mushrooms are Coprinus commatus, Amanita caserea, Cantharellus cibarius, Laccaria laccata, Russula chlorides, R. cyonoxantha, Scleroderma species, Oudemensiella radicata, Volvariella bombycina etc. These mushrooms are suggested for artificial culture in lab so as to develop mass commercial production technology. In the course of study, 13 research articles were published in different journals and proceedings. Two related reports were also submitted to UGC and DNPWC.
Performance of Mandarin Trees (Citrus Reticulata Blanco.) At Different Altitudes and Nutrient Management in Mid-Hills of Nepal
(Department of Horticulture, 2008) Baral, Dilli Ram
This work entitled “Performance of mandarin trees (Citrus reticulata Blanco.) at different altitudes and nutrient management in mid-hills of Nepal” was initiated and achieved in two phases. In the first phase, a nutritional survey based on foliar and soil analyses of the mandarin orchards located at high, mid, and low altitude citrus growing belts representing Gorkha, Lamjung and Tanahun districts, respectively and different orchard performances mainly health and age of the trees in the regions were conducted during 2003 and 2004 to elucidate the roles of these aspects on foliar as well as soil nutrient composition and to the appraisal of nutrients constraints in these regions. Two years of results showed that there was a strong association between soil fertility trends and altitudinal variations. At high citrus growing altitude (> 1100 m amsl) the total leaf P, K, Fe and Zn were higher as compared to lower altitude (500 to 1100 m amsl). Soil pH, organic matter, total N, available P, Ca, and Mg contents in soils varied according to the altitudes. Generally, soil organic matter, total soil N, available soil P were more at high altitudes and pH, available Ca and Mg contents in soils decreased as the altitudes increased. The rest of the nutrients did not show the systematic patterns with altitude variations. High performing orchards of healthy matured and young trees out-performed unhealthy trees with respect to the amount of N, P, Ca, Fe, Mn and Zn in leaf. Young mandarin trees of both healthy and unhealthy had high content of leaf, N, P, K, Mn and Zn at all the altitudes compared to mature ones. However, soil organic matter, total N and available P and Zn were affected by the orchard performances. Remaining nutrients were either no response or highly erratic with the age and health of the trees. This implicated that while taking samples for leaf and soil analyses of mandarin orchards for close interpretation of the test results, the samples needed to be taken altitudinally besides consideration of several other cultural management factors primarily age and health of the trees. Majority of the high altitudes citrus orchards were deficient in leaf Zn, Ca, Mg and Mn; at mid-altitude leaf Zn, B and Mn in leaf were deficient; at low citrus growing belts mostly N, and Zn were deficient. Based on soil test results, low soil pH, and low availability of Ca and Mg were found at high altitudes whereas N and B were shown to be in low to medium ranges in most of the orchards at medium and low altitudes. Nitrogen fertilization was found to be the most problematic nutrients based on literatures reviews and findings of the first phase of the study. So, in the second phase of the studies, the plan for field N-management of experimentation in farmer’s field conditions were initiated in 2004/05 fiscal year at Chowk-8, Dudhenkuna mandarin growing pockets of Tanahun district which is located in mid-hills (600-700 m amsl) of Western Region of Nepal. Main objectives of these studies were to elucidate the efficient roles of various N fertilization managements through its interaction with the major nutrient packages, amount and method of N application to observe trees growth, yield and quality variables of local landrace mandarin. The results showed that the efficient N fertilization management includes the soil application of complete package viz. 200-100-200 g NPK/plant/year with 2 sprays of Plantoplex (commercial formulation) and 2 kg of agri-lime per tree, the positive N–K containing fertilizer treatments interaction, the optimal N application rate of 400 g N/plant/year applied in winter and early spring for 5-6 years old trees and two basally applied N plus one foliar applied N as urea just after blossoms significantly increased number of leaves, length of shoots, number of matured and immatured fruits, fruit size and total fruit yield, peel thickness, TSS, TSS:TA ratio, and juiciness. However, flower number, TA, fruit firmness and coarseness were decreased by the above mentioned good N managements practices. The overall, these studies were achieved to suggest efficient N fertilization practices for local landrace mandarin under low zones of mid-hills of Western regions of Nepal and that resulted in the optimal production with quality fruits.

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