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Item Herbivory and pathogen damage on co-associated native and invasive plants in Suryavinayak area, Bhaktapur, Nepal .(2024) Twanabasu, Sabita; Lal B. ThapaAvailable in full textItem Ecological study of surface water bodies in Sagarmatha national park and buffer zone, Nepal(2014) Ghimire, Narayan Prasad; Pramod Kumar JhaAvailable in fulltextItem 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 PantPiper 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 ।Item Plant Species Diversity and Biomass in the Forests of Morang District, east Nepal(Institute of Science & Technology, TU, 2024-08) Gachhadar, Pramila Kumari; Dr. Chita Bahadur Baniya, Dr. Tej Narayan MandalTropical forest ecosystem is crucial for mitigating the effects of climate change, because it acts as a carbon sink. Additionally, forest is the home to a significant portion of world’s biodiversity. Species composition, diversity, and biomass thought to be changed along the increasing elevation. The objective of the present study was to determine the variation in soil characteristics and their effect on species composition, diversity, biomass, carbon and nutrient stocks in the forests located along elevation gradient in Morang district of east Nepal. Five forest sites located at different elevations were selected which are addressed here as Bhaunne (200 m), Raja-Rani (500 m), Murchungi (800 m), Adheri (1000 m) and Sagma (1200 m), which lie inside the five different community forests in Morang district. A total of 50 sampling plots, 10 from each forests were laid randomly. Sampling size for tree was 20 m x 20 m, for shrubs nested 5m x 5m and for herbs nested 1m x 1m. Soil was collected by soil monolith of 10 cm x 10 cm x 30 cm, which was also used for fine root collection and litter mass was collected by using 1 m x 1 m sampling size within the plots used for tree sampling. Trees (≥10 cm girth) biomass and shrubs biomass was estimated by girth: biomass allometric equation. Herb biomass was estimated by harvest method. The carbon content of each plant components were estimated by ash content method. The data were analyzed by MS excel and R-package. Plot wise generalized linear model up to first order showed that the total species richness, herbs species richness and shrub species richness statistically significantly inclined and tree species richness statistically significantly declined pattern with increasing elevation. Total biomass and tree biomass showed declined relationship with elevations. While, shrub biomass showed statistically not significant inclined pattern and herb biomass showed statistically significant inclined pattern with increasing elevation. Shorea robusta was a dominant tree species with the highest Important Value Index value in the four forests except Sagma. Schima wallichii was the dominant species with the highest IVI in Sagma. Sorensen’s similarity index of trees revealed 64% similarity between Murchungi and Adheri forests, while lower similarity (22%) was exhibited between Bhaunne (extreme lower elevation) and Sagma forest (extreme high elevation). Stand biomass (815.88 Mg ha-1) and carbon stock (333.63 Mg C ha-1) were maximum in lower elevation forest (Bhaunne), while minimum biomass (299.96 Mg ha-1) and carbon stock (140.19 Mg C ha-1) were found in higher elevation forest (Sagma). Litter mass ranged between 7.1 Mg ha-1 and 25.7 Mg ha-1 showing irregular trend even in carbon and nutrient stock (N, P, K) due to irregular variation in non–leaf (wood) component of litter mass. Leaf litter exhibited close C: N ratio than non-leaf (wood) litter indicating a fast decomposition and nutrient release in the ecosystem. Fine root biomass ranged from 7.14 Mg ha-1 to 16.0 Mg ha-1. Carbon and nutrient stocks in fine root followed the same trend as per the trend in biomass. Fine root of <2 mm diameter size contained higher biomass than 2-5 mm size. Further, C: N ratio in <2 mm size was narrow than 2-5 mm size which is expected to release more nutrients in the ecosystem. Soil moisture ranged between 8.48 % and 21.29 %, water holding capacity from 68.21 to 97.48%, pH from 5.06 to 5.68, organic carbon from 1.20% to 3.04%, total nitrogen from 0.12 to 0.26% in different forests located along the different elevations. The lower elevation forest (Bhaunne) contained maximum soil moisture, organic carbon and total nitrogen, representing a healthy condition for the ecosystem. The soil moisture and fine root biomass were the most significant predictors for the tree species richness. Similarly, elevation, moisture, and non-leaf litter mass were significant for shrub species richness (Elev: p < 0.01, Moist1: p < 0.01, NLP: p < 0.05). The total nitrogen and leaf litter mass were important for herb species richness with p values; < 0.001 and < 0.01 respectively. In conclusion, variation in elevation has the effect on change in soil properties, plant density, plant diversity, biomass, carbon and nutrient stocks which accumulate in interdependent way. Findings of the present study may help to formulate a strategy for the management of productive forest to mitigate the carbon emission. उष्णकटिबंधीय वन पारिस्थितिक प्रणाली महत्त्वपूर्ण छ, किनभने यसले कार्बन भण्डारको रूपमा काम गर्दछ । प्रजाति संरचना, जैविक विविधता (Biodiversity), र जैविक पिण्ड (Biomass) बढ्दो उचाइसँगै परिवर्तन हुने गर्दछ । यो अध्ययनको उद्देश्य माटोको विशेषतामा हुने भिन्नता र वनमा रहेका प्रजातिहरूको संरचना, विविधता, जैविक पदार्थ, कार्बन र पोषक तत्वको भण्डारमा प्रभावको अध्ययन हो, जसको लागि मोरङ जिल्लामा भाउने (२०० मिटर), राजा-रानी (५०० मिटर), मुरचुङ्गी (८०० मिटर), अधेरी (१००० मि.) र साग्मा वन (१२०० मि.) गरी पाँच वटा वन छनोट गरिएको थियो, जुन सामुदायिक बन अन्तर्गत पर्दछ । ५० नमूना प्लटहरू, प्रत्येक वनबाट १० प्लटहरू अनियमित ढांचा अनुसार रूख (Trees) को लागि नमूना आकार २० मि. x २० मि., बुट्यानहरू (Shrubs) को लागि ५ मि.x ५ मि. र साना झाडीहरू (Herbs) को लागि १ मि.x १ मि. थियो । माटो १० से.मि. x १० से.मि. x ३० से.मि. को मोनोलिथद्वारा संकलन गरिएको थियो, जुन मसिना जरा सङ्कलनका लागि पनि प्रयोग गरिएको गरिएको थियो । कुल प्रजातिहरू, बुट्यान र साना झाडी प्रजातिहरू बढ्दो उचाइको साथ सांख्यिकीय रूपमा महत्त्वपूर्ण बढ्दो ढाँचा देखायो र रूख प्रजातिहरू बढ्दो उचाइसँगै गिरावट प्रवृत्ति देखाएको छ । कुल जैविक पिण्ड (Total stand biomass) र रूख जैविक पिण्ड (Tree biomass) ले सांख्यिकीय रूपमा महत्त्वपूर्ण रूपमा घटेको सम्बन्ध देखाएको छ, जबकि बुट्यान जैविक पिण्ड (Shrub biomass) र झाडी प्रजातिको जैविक पिण्ड (Herb biomass) ले बढेको ढाँचा देखायो । Important Value Index को आधारमा, साल (Shorea robusta) तलको चारवटा जंगलहरुमा र चिलाउने (Schima wallichii) साग्मा (माथिल्लो) वनमा प्रभुत्व छ । सोरेन्सेनको रुखको समानता सूचकाङ्कले मुरचुङ्गी (८०० मि.) र अधेरी जंगल (१००० मि.) बीच ६४ प्रतिशत समानता देखाएको छ । जबकि भाउन्ने (२०० मि.) र साग्मा वन (१२०० मि.) बीच कम समानता (२२%) प्रदर्शन गरिएको थियो । कूल वनस्पतिमा अधिकतम जैविक पिण्ड, ८१५.८८ Mg ha-1 र कार्बन स्टक, ३३३.६३ Mg C ha-1 भाउन्ने बनमा पाइयो भने न्यूनतम बायोमास, २९९.९६ Mgha-1 र कार्बन स्टक, १४०.१९ Mg C ha-1 साग्मा वनमा पाइयो । पातपतिंगर ७.१ Mg ha-1 र २५.७ Mgha-1 को बीचमा पाइयो । मसिनो जराको जैविक पिण्ड (Fine root biomass) ७.१४ Mg ha-1 देखि १६.० Mg ha-1 सम्म, भाउने जंगलमा न्यूनतम र मुर्चुङ्गी वनमा अधिकतम पाइयो । २ मि.मी. व्यास भएको जराले अधिकतम र २-५ मि.मी.ब्यास भएको जराले कम बायोमास देखायो । माटोको आर्द्रता ८.४८ % र २१.२९ %, पानी धारण क्षमता ६८.२१ देखि ९७.४८ %, pH ५.०६ देखि ५.६८ , जैविक कार्बन १.२० % देखि ३.०४ %, कुल नाइट्रोजन ०.१२ % देखि ०.२६ % सम्म पाइयो । भाउने वनमा अधिकतम माटोको आर्द्रता, जैविक कार्बन र कुल नाइट्रोजन रहेको थियो, जसले पारिस्थितिक प्रणालीको लागि स्वस्थ अवस्थालाई जनाउछ । माटोको आर्द्रता र मसिना जरा बायोमासले रूख प्रजातिहरूको वृद्धिको लागि सबैभन्दा महत्त्वपूर्ण रहेको पाइयो । त्यसैगरी, उचाइ, आर्द्रता, र गैर-पात लिटरमास झाडी प्रजातिहरूको लागि महत्त्वपूर्ण थियो। कुल नाइट्रोजन र पात लिटरमास झाडी प्रजातिहरूको लागि महत्त्वपूर्ण पाइयो । अन्तमा, उचाइको भिन्नताले माटोको गुण, बिरुवाको घनत्व, बिरुवाको विविधता, जैविक पिण्ड, कार्बन र पोषक तत्वको भण्डारमा प्रभाव पार्छ जुन एक अर्कामा निर्भर हुन्छ । वर्तमान अध्ययनका निष्कर्षहरूले कार्बन उत्सर्जनलाई न्यूनीकरण गर्न, उर्बर र उत्पादक वन व्यवस्थापनको रणनीति बनाउन मद्दत पुग्नेछ ।Item Antifungal effects of some plant essential oils against Alternaria alternata (Fr.) Keissl. and Aspergillus niger van Tiegh. from grapes(2015) Bhattarai, Bina; Sanjay Kumar JhaThe essential oil of six plants viz. Murraya koenigii (L.) Spreng., Eucalyptus citriodora Hook., Artemisia indica Willd., Cinnamomum camphora (L.) J. Presl., Cinnamomum tamala (Buch.-Ham.) Nees and Eberm and Lantana camara L. were assessed in vitro for the antifungal activity against Alternaria alternata (Fr.) Keissl. and Aspergillus niger van Tiegh., causing postharvest rots in grapes. The test fungi were isolated from infected grapes obtained from local markets. The essential oils were extracted through hydro distillation process using Clevenger oil extracting apparatus. For screening of antifungal activity treatments at concentration of 20, 40, 80, 160 and 320 µl/ml and controls were set to determine percentage inhibition of mycelial growth of two test fungi using poisoned food technique. All the tested oils exhibited significant antifungal effect (P<0.05) over tested fungi. Among all six essential oils, Cinnamomum camphora showed the most effective antifungal activity against Aspergillus niger which inhibited the mycelial growth by 81.58 % and 100 % at 20 and 80 µl/ml oil concentration respectively. Furthermore, Cinnamomum tamala showed best antifungal effect in controlling Alternaria alternata among all six oils which inhibited the mycelial growth by 93.11 % at 20 µl/ml and by 100 % at 80 µl/ml oil concentrations.Item Antioxidant activity of selected wild orchids of Nepal(2015) Chand, Mukesh Babu; Bijaya PantThe inhibitory or delaying action of both the synthetic chemicals and naturally occurring phytochemicals against oxidative damage to tissues by free radicals produced in biological system of living organisms is known as antioxidant activity. Since some phytochemicals are responsible for biological as well as medicinal activities, nine wild orchids of Nepal were assessed for total polyphenolics and flavonoids content along with the antioxidant activity. The ethanolic extract of Eria graminifolia pseudobulbs, Gastrochilus acutifolius leaf and root, G. distichus whole plant, Luisia trichorhiza leaf and root, Otochilus albus pseudobulbs, Papillionanthe uniflora whole plant, Pholidota articulata leaf and pseudobulbs, Rhynchostylis retusa leaf, and Trudelia cristata leaf and stem were prepared by Soxhlet extraction. Phytochemicals were detected by previously established protocols with minor modifications. The total flavonoids were estimated with aluminium chloride method and total polyphenolics content with Folin-Ciocalteu phenol reagent method. Antioxidant activity was assessed by DPPH (2, 2-diphenyl-1-picryl hydrazyl) free radical scavenging assay. There was significant variation of total flavonoids, total polyphenolics content and antioxidant activity among the orchid extracts at P = 0.05. The total flavonoids varied with highest in Rhynchostylis retusa leaf (110.68 ± 4.52 mg QE/g) and lowest content in Gastrochilus acutifolius root (22.32 ± 1.10 mg QE/g); total polyphenolics with highest in Trudelia cristata stem (69.68±2.78 mg GAE/g) and lowest content in Gastrochilus acutifolius leaves (11.89±0.64 mg GAE/g). Also, the antioxidant activity varied with highest in Trudelia cristata stem (IC 79.69 µg/ml) and lowest DPPH radical scavenging activity in Gastrochilus acutifolius leaf (IC 50 µg/ml). However, none of the orchid extracts were as effective as quercetin – the reference compound – in radical scavenging activity (IC 32.90 µg/ml). Total polyphenolics and flavonoids content and antioxidant activity of selected orchid extracts in this study were higher or lower than medicinal plant and orchid extracts of previous studies with considerable margin. Again, their antioxidant activity was positively associated with total flavonoids and total polyphenolics content. Hence, this study claims that the ethanol extract of selected wild orchids perform significantly varying antioxidant activity with further possibilities of pharmacognistical and pharmacological studies.Item Biological activities of in vitro generated callus of Neopicrorhiza Scrophulariiflora (pennell) D.Y. Hong,a Himalayan Medicinal Plant(2024) Tiwari, Kiran; Mukti Ram PaudelAvailable in fulltextItem Climate change patterns and impacts as revealed by local perceptions and scientific records in a mountain Village of central Nepal(2024) Dhungel, Uma; Chitra B. BaniyaAvailable in fulltextItem Habitat suitability of Globally worst Invasive weed, Sphagneticola trilobato(L.) paruski in South Asia(2024) Aryal, Puspa; Bharat Babu ShresthaAvailable in fulltextItem Population Ecology and Harvesting Sustainability of Neopicrorhiza scrophulariiflora in Nepal Himalaya(Institute of Science & Technology, T.U., 2024-06) Poudeyal, Mukti Ram; Prof.Dr. Suresh Kumar GhimireWild plant resources, including especially medicinal and aromatic plants (MAP) have great ecological, cultural, and economic value and contribute significantly to people's livelihoods in many of the world's rural areas. Additionally, it is widely acknowledged that the sustainable use of MAPs derived from natural ecosystems is an essential instrument for enhancing rural economies and forest protection through poverty reduction. A number of connected issues of social, ecological, cultural, and environmental character must be addressed when the commercialization and sustainable use of wild MAPs are envisioned in a single paradigm. This thesis takes a step in that direction and uses a social-ecological approach to develop a model for sustainable harvesting of Neopicrorhiza scrophulariiflora which seeks to create consistency between production and the renewable resource supply from the Nepalese Himalayas. We concentrate on how ecological changes drastically altered plant distribution and how resource availability connects to usage patterns across Nepal (via trade and transportation systems). We tested whether the variation of harvest (experimental harvest: removal of 0-100% of the plants) and the ecological conditions (lower alpine, <4250 m, vs upper alpine, >4250 m) affect population structure, reproduction, growth rates, and population dynamics in commercially open and protected regions in northwestern and north-central Nepal. The area of the potential distribution of the species was calculated to be 11617 km2, corresponding to 8% of Nepal's land area and primarily located in the eastern highlands. Particularly suitable habitat areas (386 km2; 0.3% of the land area) tended to lie in the narrow altitude range of 4000-4400 m above sea level, especially in the central and eastern regions. The plant species prefer mild temperatures and sufficient rainfall in the middle of the growing period (June-August), and such conditions often occur in the mentioned areas. On the other hand, decreasing rainfall and greater temperatures diminished the suitability of the habitat in the western regions where the populations are intensively harvested with a view to commercial exploitation. Over 12 fiscal years, available official records showed that a total quantity of dried rhizomes of 372 tons (31 tons/year) valued at USD 591570 was exported to other countries. Of this, 92% of the amount came from western Nepal, which indicates that the current resource utilization is not sustainable. In the protected area, the recent harvest, which was largely carried out by locals (de facto harvest), had a positive effect on population density for vegetative and a negative effect on reproductive individuals, while it had a negative effect on all plant stages in the area where exploitation is unregulated. Harvesting involves a trade-off between vegetative regrowth (clones) and sexual reproduction, and flowering was reduced when harvesting intensity increased. Apparently, the growth rate of the populations is positive and occurs predominantly by clonal reproduction in the unregulated area and sexual reproduction in the protected area. Clonal behavior, such as fugitive recruitment and accelerated bud production, can help a plant mitigate the detrimental impacts of harvesting and, theoretically, boost the harvest potential. Mixed-effects statistical models were used to model data from simulated harvest experiments and showed that recovery of population density and sexual reproduction varied significantly depending on harvest treatments and pre-harvest plant density. In lower alpine populations at the protected site, both density and reproduction were restored within three years after harvesting up to 50% of the plants, and within one year after harvesting up to 25% of the plants. In contrast, recovery to pre-harvest conditions at the unregulated site was only achieved after one year of harvesting 25% of the plants. Post-harvest recovery was slower at higher altitudes (upper alpine, >4250 m) and plots with more intensive harvesting (>50% harvesting) recovered more slowly. Based on matrix modeling, it was found that the population growth rate (λ) when removing up to 25% of the plants made it possible to maintain the pre-harvest condition at a 2-year harvest interval in almost all the studied populations. In the protected area, population growth was unaffected by the removal of up to 50%, and instead, the growth rate increased more than in the control plots. At the high alpine sites in the unregulated area, however, the growth rate was decreasing, even on the control plots, and harvesting had a further detrimental effect on the populations, making it necessary to use relatively long time intervals between harvests to achieve stability. Selective harvesting of particular developmental stages was difficult to achieve, nevertheless, it is considered worthwhile to leave 20-25% of the fruiting ramets at each harvest if 25% of the plants have flowered. In general, we strongly recommend that in order to achieve sustainable harvesting spatio-temporal rotations be introduced, so that a time interval of at least four years is achieved between harvesting activities in a given area and so that the plants are given a minimum amount of time to mature. वनजन्य वनस्पतिहरु मध्ये बिशेषगरी औषधिजन्य जडिवुटिको पास्थितीक, सांस्कृतिक तथा आर्थिक महत्व रहेको हुन्छ । संसारभरिनै जडिवुटिको परम्परागत स्थानिय औषधोपचार तथा बेचविखनबाट हुने नगद आम्दानीलाई ग्रामिण आधारभूत आवश्यकता र जनजीविकाको आयआर्जनको मेरुदण्दको रुपमा लिइन्छ । यसको दिगो संकलन र व्यबस्थापनलाई गरिबी निबारण तथा वनको संरक्षण सम्बर्धन गर्ने महत्वपुर्ण औजारको रुपमा पनि लिर्ईएको पाईन्छ । तर जब औषधिजन्य जडिवुटि वनस्पतिको व्यापारिकरण संगसँगै बढ्दो माग तथा बजार मूल्य र त्यस अनुसारको दोहन एउटै परिदृश्यमा देखा पर्दछ त्यसैसंगै आउने सामाजिक, आर्थिक तथा सांस्कृतिक अवयवहरुलाई समन्वात्मक तवरले समाधान खोजीनु अपरिहार्य रहन्छ । यीनै समस्या समाधानको शुत्राधारको लागि जडिवुटिको सामाजिक–पारिस्थितिक अवधारणालाई लिएर स्रोतको अनवरत उत्पादन, प्रयाप्तता तथा समुचित प्रयोगार्थको लागि सदियौंदेखि उपचार पद्दतीमा आईरहेको तथा राष्ट्रिय र अन्तरराष्ट्रिय व्यापारिकरण भई दोहन भईरहेको उच्च हिमाली वनस्पति कुट्की (न्योपिक्रोराईजा स्क्रोफुलारीफ्लोरा) को दिगो संकलनको विधि, धाचा तथा दिर्घकालीन व्यावस्थापन रणनिती तयार पार्न सहयोग गर्नु नै यो शोधकार्यको प्रमुख उद्देश्य हो । विशिष्टिकृत रुपमा नेपालभरी पारिस्थिक प्रणाली अनुसार प्राकृतिक विचरणमा पार्ने प्रभाव, स्रोतको उपलब्धता, प्रयाप्तता तथा सुनिश्चितताका र त्यस अनुसारको संकलन, बेचबिखन र पैठारी रहेको वा नरहेको छुट्याउनु नै अध्ययनको पहिलो उद्देश्य थियो । त्यस्तैगरी भिन्न पारिस्थिक प्रणाली [उच्च 󠆅(समुन्द्रि सतह बाट ४२५० मि. भन्दा कम) तथा न्युन (समुन्द्रि सतह बाट ४२५० मि. भन्दा बढि) हिमाच्छेदीत भूभागहरुम] अनुसार विभिन्न स्तरको (०%, पूर्ण नियन्त्रण देखि १००%) कटान परिक्षण प्रयोग गर्दा विरुवाको जनसांखिक संरचना, प्रजनन क्षमता, वृद्धिविकाश तथा समग्र जनसांखिक बनोटको उलट–पुलटमा पार्ने प्रभावको मुल्यांकन गर्ने र न्युन क्षतिमा उच्चतम लाभ लिने विधि पत्ता लगाउनु सोधकार्यको अर्को उद्देश्य थियो । यसका लागि नेपालको उत्तरी हिमाली भूभागमा स्थानिय प्रयोगको लागि तथा व्यापारिक कटान तथा संकलनका लागि खुल्ला अपिनाम्पा संरक्षण क्षेत्र र व्यापारिक संकलनका लागि प्रतिबन्धित लाङ्टाङ राष्ट्रिय निकुञ्जमा दिर्घकालिन प्लट बनाई सन् २०१५ देखि २०१८ सम्म परिक्षण अध्ययन गरियो । जि. आई. एस्. विधिको अध्ययन अनुसार नेपालमा कुट्कीको संभावित विचरण क्षेत्र ११६१७ स्क्वाएर कि. मि. (करिब ८%) रहेको छ । जसमध्ये पुर्वी तथा मध्य उच्च पहाडी भूभागको ३८६ स्क्वाएर कि. मि., करिब ०.३% मात्र उत्तम गुणस्तरीय वासस्थान पाईएको र समुन्द्रि सतहबाट ४००० मि. देखि ४४०० मि. को उचाईमा मात्र साघुरिएर रहेको पाईन्छ । वातावरणीय अनुकुलनताको आधारमा विरुवाले उसको उच्चतम वृद्धि हुने समय जस्तै जून देखि अगस्त महिनामा मध्यमस्तरीय तापक्रम र उचित मात्राको बर्षात हुने ठाँउमा राम्रो भएको पाईयो । छोटो तथा न्युन बर्षात र उच्च तापक्रमका कारणले गर्दा पश्चिम नेपालतिर वासस्थानको गुणस्तर घट्दै गएको पाईन्छ । बिगत १२ बर्षको सरकारी आँकडा अनुसार नेपालबाट जम्मा ३७२ टन (मूल्यः करिब ५९१५७० अमेरिकन डलर, औसतमा प्रतिवर्ष ३१ टन) निकासी हुने गरेको र सबै तौलको करिब ९२% पश्चिम नेपालबाट मात्र भएको पाईयो । अधिक न्युन गुणस्तरको वासस्थानको उपलब्धता तथा अधिक दोहनलाई सँगै जोडेर हेर्दा समग्र नेपालमा अहिलेको संकलन प्रणाली दिगो नभएको पाईएको छ । तथापि व्यापारिक रुपमा खुल्ला तथा प्रतिबन्धित क्षेत्रमा भएको भौगोलिक प्रत्यक्ष अध्ययनमा स्थानिय उपचारको लागि गरिने परम्परागत संकलन परिमाण दर उस्तै रहेको पाईएको छ । कुट्कीको जनघनत्वमा भैरहेको स्थानिय तदर्थ दोहनको प्रभाव मुल्यांकन गर्दा प्रजनन र अप्रजनन दुवै अवस्थाका विरुवामा खुल्ला क्षेत्रमा नकारात्मक असर रहेको तर प्रतिबन्धित क्षेत्रमा अप्रजनन अवस्थाका विरुवामा सकारात्मक असर रहेको थियो । मध्यम स्तरको दोहनले प्रजनन र अप्रजनन वृद्धिको छेकबार/बन्देजलाई बढाउने सेतुको रुपमा रहेको र जव दोहनको स्तर बढ्छ विरुवामा कोपिला लाग्ने दर रेट घटेको पाइयो । अतः विरुवाको जनसांखिक वृद्धि खुल्ला क्षेत्रमा अप्रजनन प्रसारणसँग र प्रतिबन्धित क्षेत्रमा प्रजनन प्रसारणसँग केहि सकारात्मक सम्बन्ध रहेको थियो । विरुवामा रहेको अप्रजनन प्रसारणजन्य गुणहरु जस्तै मौका मिल्दा हुने अप्रत्यासीत अंकुरण क्षमता तथा सामान्य अवरोधको बदलाभमा नयाँ नयाँ पालुवा अंकुरण हुने क्षमताको बिस्तार गर्न सक्ने शंचित शक्ति प्राकृतिक रुपमै भएकाले कुट्कीमा केहि हदसम्म कटानको नकारात्मक प्रभावलाई सहन सक्ने निष्कर्श निकालियो । तथ्यांकीय विष्लेशण रिपिटेड मिक्स्ड इफेक्ट मोडलीङ्का अनुसार कटान संकलन पश्चात हुने जनघनत्व अंकुरण भरण तथा प्रजनन उत्पादन संकलन—कटान दरमा तथा कटान गर्नु भन्दा अगावैको जनघनत्वमा भरपर्ने र सकारात्मक सम्बन्ध रहेको पाईयो । प्रतिबन्धित क्षेत्रको न्युन (समुन्द्रि सतह बाट ४२५० मि. कम) हिमाच्छेदीत भूभागमा ५०% सम्म कटान गर्दा परिक्षण अवधिको तिन वर्षमै पुनःभरण भएको र २५% सम्मको कटान प्रत्येक वर्ष गर्दा पनि पुनःभरण हुने परिणाम पाईयो । तर खुल्ला क्षेत्रको समान स्तरको भूभागमा उक्त अवधिमा २५% कटान मात्र पुनःभरण भएको पाईयो । कटान पश्चातको पुनःभरण क्षमता भौगोलिक उचाई बढ्दा तथा कटान प्रतिशत दर बढाउदा घटेको पाईयो । पुनःभरण क्षमता प्रतिबन्धित क्षेत्रको तुलनामा खुल्ला क्षेत्रमा धेरै ढिलो भएको पाईएको छ । अर्को तथ्यांकीय विष्लेशण म्याट्रिक्स मोडलीङ्का अनुसार लगभग सबै ठाँउमा विरुवाको जनसांखिक वृद्घिदर २५% सम्म कटानको दुई बर्षको अवधिमै सकारात्मक स्तर भन्दा माथि रहेको पाईयो । बिषेशगरी प्रतिबन्धित क्षेत्रको न्युन हिमाच्छेदीत भूभागमा ५०% सम्मको कटानले विरुवाको जनसांखिक वृद्घिदर उक्त अवधिमै कटान परिक्षण अगाडिको भन्दा अझ वढेको भेटिएको छ । तर खुल्ला क्षेत्रको उच्च हिमाच्छेदीत भूभागमा जनसांखिक वृद्घिदर कटान नियन्त्रित परिक्षण अवस्थामै पनि घटिरहेको हाम्रो अध्ययनमा पाईयो । विरुवाको जनसांखिक मुल्यांकन अनुसार परिपक्व उमेरको विरुवा छनौट विधिबाट गरिने कटान संकलन त्यति व्यावाहरिक नभएको र प्रत्येक कटान समयमा कम्तिमा २०—२५% फूलफल लागेका विरुवा रहने गरी भएमा वा प्रत्येक जनसांखिक संरचनामा उक्त २०—२५% फूलफल लागेका विरुवा सुनिश्चित भएमा मात्र कटान अनुमति दिन मिल्ने देखिन्छ । कुट्कीको दिगो संकलन, क्षति न्यूनिकरण, र जनसांखिक सुनिश्चितताका लागि समय र ठाँउ अनुसारको रणनितिक कटान—संकलन व्यावस्थापन गर्नुपर्ने र प्रत्येक चार बर्षे अन्तरालको अवधिमा मात्र कटान अनुमति दिन सकिने यो सोधकार्यको सुझाव रहेको छ ।Item Myxomycetes of Shivapuri and Godawari (Kathmandu Valley), Central Nepal(Department of Botany, 2010) Chuhan, Ananta BahadurMyxomycetes are the group of fungi, which are distinct from the rest fungi because of their plasmodial characteristics. Plasmodium is a vegetative phase of Myxomycetes, which consist of many nuclei. Most of the slime moulds are saprophyte growing in damp, shady places, in wood on rotten logs, stumps or in dung in pasture. The study is focused on the exploration of Myxomycetes from the Shivapuri and Godawari hills, the protected forests of Central Nepal. Though Ceratiomyxale has been excluded from the Myxomycetes, this has been included in the thesis at present. The collection of slime molds was done from first week of September to last week of October in 2007 and 2008 just after the seven days of heavy rainfall which is suitable time for the formation of fruiting bodies of many species. The collected specimens were placed in a small box by a drop of white glue to protect fragile specimens. The specimens were examined carefully by naked eyes for observing the details of morphological characters. The microscopic characteristics of fungi were studied under stereo-microscope. Ornamentation of capillitium and spores were observed through microscope. Though, more than 35 specimens were collected in 2007 and 2008 only 12 species of 9 different genera and 5 orders were identified heaving call. no.1,4,5,7,10,11,15,16,20,27,32,35. Identified species were Arcyria pomiformis, Arcyria incarnata, Arcyria cineria, Stemoitis sp., Didymium flexuosum, Physarum viride., Hemitrichia serpula., Tubifera microsperma, Ceratiomyxa fruticulosa., Fuligo cinerea., Mucilago crustacea and Didymium iridis.Item Population structure and plant performance of Juniperus Squamata Buch.-Ham. ex D. Don along an elevation gradient in Manang, Nepal(Department of Botany, 2016) Upadhaya Subedi, PremNot availableItem Phytochemical screening of rhizome of paris polyphylla Sm.for antibacterial and antioxidant investigation(Department of Botany, 2016) Sharma, SirjanaParis polyphylla Sm. is a medicinal plant listed as vulnerable (V) under IUCN threat category. The whole plant has medicinal value. The rhizomes have high demands in both national and international markets for its valuable rootstock to treat variety of ailments. Root paste is applied as an antidote to snake bites and poisonous insect bites and also to alleviate narcotic effects.It can be applied to wounds for rapid healing and also for fever, headache, and stomach problems of both man and animals. It is found to be used as a primary herb in the treatment of throat infection, breast cancer in traditional Chinese medicine. In the present experiment, rhizome sample of Paris polyphyllawascollected from different localities.Crude methanol extract was prepared from each sample using soxhlet apparatus and used for different experiments. Chemical test method was used for primary phytochemical screening.Primary phytochemical screening revealed the presence of alkaloids, flavonoids, tannins, phenols, terpenoids, glycosides and saponins in all the samples. Total polyphenol content was estimated using the Folin-Ciocalteu phenol reagent and flavonoid content using Aluminium chloride colorimetric method with slight modifications. Highest polyphenol and flavonoid content values of 44.83±0.33mgGAE/gm and 6.28±0.035mgQ/gm respectively were observed in wild sample of Dolakha whereas lowest total polyphenol and flavonoid content values of 36.89±0.074mgGAEgm and 4.56±0.22mgQ/gm respectively were observed in wild sample of Parbat district. Similarly antioxidant activity was determined using DPPH assay. It was measured in terms of IC50 value of plant extract. Plant extract having lowest IC50 value was considered as better antioxidant. Maximum IC50 value (47.59±1.2843) was observed in wild sample of Parbat district and minimum IC50 value (42.63±1.4389) was observed in wild sample of Dolakha district. Antibacterial activity was determined usingagar well diffusion method.Plant extract exhibited zone of inhibition against Bacillus subtilisbacterium with maximum zone of inhibition of 14mmin the wild sample collected from Dolakha. In this way it has been concluded that Paris polyphyllais an important medicinal herb of Nepal. Among the collected samples, sample from Dolakha(wild) was found to have higher antibacterial and antioxidant potential.Item Community Structure and Regeneration of Sub-alpine Abies spectabilis (D.Don) Mirb. Forest in Sagarmatha National Park, Eastern Nepal(Department of Botany, 2012) Nagarkoti, Amrit BahadurCommunity structure and regeneration pattern of Himalayan Fir, Abies spectabilis (D.Don) Mirb was studied along the elevation gradient 27500 to 3550 m. asl in mixed Abies spectabilis forest located between Guranse danda and Khumjung area of Sagarmatha National Park, Eastern Nepal (Central Himalaya). Vegetation in the study area was sampled through systematic random sampling method. A total of 45 plots of 0.1 ha (33 m x 33 m) were sampled between 2750 m to 3550 m each at 100 m elevation interval. Nine vertical transects were defined within the study area and quadrats were located along each transects. Five sampling plots were laid in each elevation one or the both side of the well-established footpath. The location for the first plot in each elevation was chosen on the side of the path where there was at least one mature Abies spectabilis tree was. The distance between two transects were between 30-200m.Other plots in the same elevation were laid at a distance of 30-200 m difference. The distance between the plots was determined on the basis of the accessibility and presence of Abies spectabilis trees. If Abies trees were not observed along the sampling transect,a sidewise search was conducted on either side of the path at the same elevation. Canopy cover, rock cover, logging, lopping, litter and grazing/trampling damage in each quadrat were determined by visual estimation method. Soil samples were collected from each quadrat from its four corners and their physiochemical characteristics were analyzed. Number of woody plant species, number of individuals of each tree species, diameter at breast height (DBH) of each individual tree, number of seedlings and saplings of tree species were recorded in each quadrat. Various community attributes (e.g. importance percentage, species diversity and beta diversity) and population characteristics (e.g. density- diameter bar diagram) were analyzed. Ordination methods were used to analyze species composition and to relate this to environmental variables. Generalized linear models were used to relate community attributes with environmental variables. Soil was slightly acidic with soil pH value 5.16. Soil carbon and soil nitrogen were 3.05% and 0.27% respectively. Thirty four species were recorded from the study forest. Rhododendron arboreum was the dominant tree species with the highest importance percentage (61.91%) and Abies spectabilis was the co-dominant species (22.72%). The value of beta-diversity for tree was 1.26. Simpson’s Index (0.44) which was less than Shannon Wiener’s Index (1.21). Species diversity of the forest was relatively high. Total tree density was highest at 3450m and lowest at 3550m. Total tree density found changed with increasing elevation but it decreased from 3550 m towards treeline. Density-diameter curve for all trees measured was nearly reverse J- shaped that indicate a continuous regeneration trend. But the slightly deviation in the curve for Abies spectabilis alone from the typical reverse J-shaped, indicate a discontinuous regeneration pattern. The seedling and sapling distribution were not found uniform however 40% of the studied sub-plots were with seedlings while 66.67% without sapling and 40% of plot had no Abies spectabilis trees. Seedling mortality was found relatively medium and development of seedlings into saplings was also low. The lower number of sapling might be due to moderate disturbance (grazing and trampling) by livestock or environmental factors. Therefore, regeneration of Abies spectabilis was not sustainable. Keywords: Central Himalayan; Community structure; species richness elevation gradient ; regeneration ; Abies spectabilis; multivariate analyses; DCA; beta diversity; Simpson’s index; density-diameter curve; correlation coefficient matrix; GLM regression.Item Bryoflora of lowland Nepal: Tarai and Churia HIlls(Institute of Science and Technology, Botany, 2008) Pradhan, NirmalaThough the study of bryophytes in Nepal was initiated long time before but was focused mainly upon the Himalayan species. Few available literatures on Nepalese mosses and liverworts provide very scarce information about lowland species which occur below 1000 m of elevation. My aim with this research is to explore out details of lowland bryophytes which are distributed along the east to the west lowland stripe as no such study has ever been done. This study was quite fruitful to come up with many new findings and also explored many interesting rare species which demand effective conservation measures. In connection to this research, I had an opportunity to visit the National Botanical Research Institute (NBRI), Lucknow, India where I got privilege to make a brief study on their collections and with appreciable cooperation of Dr. Virendra Nath, a Senior Bryologist; I was able to confirm some of the confusing species that I had taken with me. Some species which were not identified in Nepal were also sent to Edinburgh, UK where the well known bryologist Dr. David Long who is also my Co-Supervisor in this research shared his valuable time to identify them all. Mostly, the identification work was done at the Natural History Museum and Central Department of Botany, Tribhuvan University. Bryophyte has gained least popularity among the communities and societies of Nepal. Its sustainable use is absolutely unknown among the peoples of low land districts where this study was conducted. Some species of bryophytes carry high medicinal values like Sphagnum species which also occurs in Nepal. Bryophytes have been used for various purposes especially for horticulture, packing, as medicine for cough and cold, as green tea, stuffing materials in cushions and pillows etc. These valuable species also exist in lowland Nepal but needs education and information to village peoples about sustainable uses. This kind of practice can be expected to raise their socio-economical status. The research result of this work is incorporated into my PhD. Dissertation and is submitted to the Central Department of Botany, Tribhuvan University, Nepal. Every bryofloral species recorded in the field has been included in this work including their diagnostic features, key characters, distributional and altitudinal ranges, status and references. Hand sketching of many of the species has also been provided. This research includes some significant objectives like the survey of lowland bryophytes and their documentation, status categorization, distributional range, ecology and anatomical features of every known species of lowland Nepal. This extensive research has been expected to provide good reference to all the bryologists who are interested or study low land bryophytes of Nepal.Item Floristic diversity and altitudinal variation of tree species in lower Kanchenjungha Singhalila Ridge, Eastern Nepal(Department of Botany, 2009) Khatri Chhetri, Nar BahadurThe present paper is based on the findings of floristic diversity inventory research work conducted in Lower Kanchenjungha Singhalila Ridge, in Nepal sides of Eastern Himalaya. Knowledge on floristic diversity of particular area can reflect the total resources, their use and conservation status which is very helpful for making necessary conservation strategies and policies. Eastern Himalaya is one of the globally important sites representing the important biodiversity hotspots of the South Asia. Analysis of vegetation helps to develop detailed picture of plant communities of particular geographical location. Plants specimens were collected by two field visits viz. pre-monsoon and post-monsoon during the period of June-October, 2007. Total 50 square quadrats of 10mx10m sized were laid down following stratified-random sampling method for sampling trees. In each 10m×10m quadrats, the number of individual trees was counted and dbh [diameter at breast height-1.37m, dbh ≥ 10 cm] of each tree was measured. After preservation, identification and management of collected plants, herbarium specimens were prepared and deposited in National Herbarium and Plant Laboratories, Godavari, Lalitpur (KATH) and Tribhuvan University Central Herbarium, Kirtipur (TUCH). Present study recorded 299 species among them seven species were identified only family level, 22 species only generic level rest of them to species level falling under 184 genera and 86 families. Dicots belong to 69 families, 150 genera and 229 species whereas Monocots include 15 families 32 genera and 39 species. Similarly, Gymnosperms represented two families, two genera and two species. Floristic analysis showed that Rosaceae was the largest family with 23 species followed by Ericaceae 17, and Lauraceae 9 species. The study furnished three new addition to the flora of Nepal viz. Begonia flaviflora H. Hara (Begoniaceae), Carex cruciata Wahlenberg var. argocarpa C. B. Clarke (Cyperaceae), and Strobilanthes helicta Anderson (Acanthaceae). This study also mentioned 11 threatened species of different categories and one endemic species Heracleum lallii (Umbelliferae). 30 tree species were recorded from the altitudinal range of 2100-3000m. Eurya acuminata and Symplocos species were dominant in lower elevation whereas Lithocarpus pachyphylla and Rhododendron species were dominant in upper elevation range. The diversity of tree species showed hump shape relation with elevation gradient.Item Antibacterial activity of selected orchid species of Nepal(Department of Botany, 2023) Dulal, SajanOrchidaceae, a highly advanced and widely spread family of monocotyledonous plants. Orchids have been found to contain a rich source of natural compounds with significant therapeutic activities against various disease. So this study mainly focused on antibacterial activity to generate natural medicines to substitute synthetic drugs. The orchid plants were collected from various regions of Nepal and subsequent extract preparation and laboratory work conducted at the Annapurna Research Center. A total of fifteen orchid species were selected for the purpose of this study. The different parts of orchids were used for extraction using methanol through a combination of the Percolation and intermittent sonication methods. After that in vitro antibacterial evaluation was conducted using the agar well diffusion technique with different concentration. Out of 15 species, the highest yield was obtained from Habenaria marginata 15%, and the lowest was from Coelogyne stricta 1%. In the qualitative analysis, various reagents were used to quantify tannins, flavonoids, glycosides, phenols and alkaloids. A qualitative phytochemical screening indicate that alkaloids and flavonoids were present in the extracts of all the orchid species that were tested. Both Phenol and Carbohydrate were absence in Coelogyne stricta and Eria graminifolia. The antibacterial activity of the methanol extracts from these plants was evaluated against medically significant bacteria. Enterococcus faecalis, Acinetobacter baumannii, Escherichia coli and Shigella sonnei were Gram negative whereas Staphylococcus aureus was Gram positive bacteria. All 15 plants showed activity against at least one bacterium. The two orchid plants, Coelogyne stricta and Otochilus albus, exhibited broad-spectrum activity by showing a high zone of inhibition against all tested bacteria with zone of inhibition (20mm) and (21mm) against Acinobacter baumannii respectively. Similarly, The MIC values for the tested orchid extracts range from 1.25 mg/ml to 2.5 mg/ml, while the MBC values range from 0.3125 mg/ml to 0.625 mg/ml. So Otochilus albus exhibits strong antibacterial properties against Acinobacter baumannii species, and its corresponding MIC and MBC values provide further evidence of its antibacterial effectiveness. Therefore, it is worthy to conduct additional investigations into this specific species to reveal its potential benefits. Furthermore, there is scope for conducting additional laboratory experiments and research work to develop new pharmaceutical products. Keywords: Orchids, Phytochemical compounds, Antibacterial activity, MBC, MICItem Floral Species Richness Pattern in Arghakhanchi and Adjoining Areas, Nepal(Institute of Science & Technology, 2023-12) Nepali, BaburamThe 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.Item Taxonomic revision of the Genus Crotalaria L. (Fabaceae) in Nepal(Department of Botany, 2024) Parajuli, BishnuCrotalaria L. is a large genus of the family Fabaceae with 702 species worldwide. Due to this large number of species in this genus, none of the studies till yet have been able to include all the species in their study. Different taxonomic research has found to comprise one or few Nepalese species but comprehensive taxonomic study including all the Nepalese species was lacking. This study was carried out to make a comparative and comprehensive study of detailed morphological structures, distribution patterns, and reproductive phenology. Field observations, sample collection and detail herbarium study of national and international herbaria from a taxonomic point of view was done. Some anatomical observations were also done preparing temporary slide. Many morphological characters related to shape, size, surface, orientation and position of different vegetative (stem, stipule, leaf, bract, bracteoles and peduncle) and reproductive (inflorescence, flower, calyx, standard petals, ovary, style, fruit and seed) structures of Crotalaria species are found to be important as diagnostic characters and for taxonomic delimitation. Total 18 species are found to be present in Nepal. Among them, 15 are native, one is naturalized (C. pallida) and two are exotic (C. micans and C. juncea). C. juncea is cultivated exotic, while the state of C. micans in nature needs further exploration, as the labels of herbarium specimens of this species deposited at TUCH show they have also been collected from the wild. Excluding two exotic species, 16 species are distributed in three different sections (Calycinae, Crotalaria and Hedriocarpae) but section of C. acicularis is still unclear. Due to some distinctive differences in some morphological aspects of the plant like (habit, leaf texture, color, size and surface of fruit) there are two probable new varieties of C. prostrata. Crotalaria quinquefolia has been recollected after 60 years from the same district. Crotalaria species are found to be widely distributed within Nepal from east to west. The most suitable bioclimatic zones for Crotalaria in Nepal are found to be tropical and subtropical zones but two species (C. calycina and C. sessiliflora) are found up to sub-alpine zone as well. With the exception of the endemic species C. kanaii all the other species are common to SE Asia. Among the micromorphological characters, Leaf epidermal cell shape and cell wall pattern both did not show much significance, but stomatal index can be used in combination with macromorphological characters in species delimitation. Regarding phenological patterns, flowering has been found to viii begin in three different seasons. The majority of species start flowering in summer, C. medicaginea in spring while other flowers in early autumn (C. spectabilis and C. calycina) to mid-autumn (C. acicularis and C. quinquefolia). Moreover, based on overall similarity, cluster analysis showed C. acicularis and C. prostrata as being very close, while the two species, C. sessiliflora and C. calycina, although having similar appearance, stomatal index value, and distributional elevational range, were not found to be closely associated in cluster analysis.Item Utilization Pattern and Conservation Status of Plant Resources of Makawanpur District,Central Nepal(Institute of Science and Technology, Botany, 2014) Joshi (Pradhan), NirmalaThe study is focused to document angiospermic flora, utilization pattern of useful plant resources and assess in situ conservation status of selected useful plants. Freelisting and semi-structured interviews applied to document traditional knowledge (TK) on medicinal plants, wild edible plants and their uses among respondents from Bankaria, Newar and Tamang ethnic groups. Smith's salience index (SI), informant consensus factor (ICF) or informant agreement ratio (IAR), relative frequency of citation (RFC), and cultural importance index (CI) were used to compare cultural salience of plants. Altogether, 695 species belonging to 472 genera and 124 families of angiospermic plants were collected from the study area. Leguminosae was the dominant family with 60 species and Compositae was the second largest family. Merremia hirta (Linn.) Merr., a species belonging to Convolvulaceae was collected as new addition to the flora of Nepal. A total of 189 medicinal plants, 97 wild vegetables and 65 wild fruits and nuts were documented, of which, 12 medicinal plants were found to be new method of use for the treatment of diseases. Two wild vegetables were found new addition for useful plants of Nepal. Tamang and Bankaria ethnic groups have better knowledge of utilization of medicinal and wild edible plants than the Newar ethnic group. Highest RFC and CI values were found for Urtica dioica, Swertia chirayita, Bergenia ciliata, and Centella asiatica, while SI values were highest for Terminalia alata, Phyllanthus emblica and Astilbe rivularis. The ICF values highlighted that the medicinal plants were commonly used for treating digestive system, infections/infestations and pregnancy/birth disorders. Similarly, Diplazium esculentum, Dryopteris cochleata, Tectaria coadunata, Amaranthus lividus, and Dioscorea hamiltonii are the most commonly used wild vegetables; whereas Myrica esculenta, Rubus ellipticus, Aegle marmelos, Choerospondias axillaris, and Diploknema butyracea are commonly used wild fruits. Based on rapid vulnerability assessment (RVA), 12 species such as Bergenia ciliata, Dioscorea deltoidea, Asparagus racemosus, Paris polyphylla, Podophyllum hexandrum, Aconitum spicatum, Didymocarpus pedicillatus, Aconitum laciniatum, Astilbe rivularis, Cucurligo orchioides, Rauvolfia serpentia, and Swertia chirayita were vii found to be highly vulnerable medicinal plants. This study contributes to the documentation of utilization pattern and conservation status of useful plant resources of Makawanpur district. The useful plant resources play a significant role in the medicine, income generation and nutrition of local communities. However, more research is needed in pharmacological screening and nutritional values of less known medicinal and edible plants for value addition.