Botany
Permanent URI for this collectionhttps://hdl.handle.net/20.500.14540/124
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Item Heavy Metals Accumulation in Some Trees Growing around Hongshi Shivam Cement Factory, Nawalparasi, Nepal(Amrit Campus, 2024-09-03) Bal Krishna Sapkota; Prof. Dr. Mukesh Kumar ChettriFull Text AvailableItem In-Situ Litter Decomposition and Nutrient Release in Different Tree Species of Gaurishankar Conservation Area, Nepal(Amrit Campus, 2024-08-14) Samikshya Acharya; Prof. Dr. Mohan Prasad DevkotaFull Text AvailableItem Ethnobotanical Study of Plants Used for Maternal and Child Health Care by Tharu Tribe of Dang District, Western Nepal(Amrit Campus, 2023-09-09) Sangita Chaudhary; Dr. Giri Prasad JoshiItem Air Pollution Tolerance Index and Anticipated Performance Index of Some Plant Species in Morang District, Nepal(Amrit Campus, 2024-09-20) Uma Shrestha; Dr. Anjana DevkotaAvailable Full TextItem Study of Variation in Leaf Trait and Soil Nutrients in Schima Wallichii and Quercus Leucotrichophora at Shivapuri Nagarjun National Park, Nepal(Amrit Campus, 2023-04-10) Sumitra Dahal; Prof. Dr. Kanta PoudyalAvailable Full TextItem Diversity, Distribution and Use of Non-Timber Forest Products in the Ekata Community Forest of Nawalparasi (East), Nepal(Amrit Campus, 2024-05-03) Sharada Neupane; Dr. Yadav UpretiAvailable Full TextItem Ethnomedical Study in the Rubivalley Rural Municipality Dhading, Central Nepal(Amrit Campus, 2024-05-28) Saroj Adhikari; Dr. Giri Prasad JoshiAvailable Full TextItem Dicot Flora of Sworgadwari Hill in Pyuthan District, Western Nepal(Amrit Campus, 2024-09-09) Sadikshya Gautam; Prof. Dr. Devendra Mananda BajracharyaAvailable Full TextItem Soil Organic Carbon and Fungal Population in Different Land Use Types of Chapagaun, Lalitpur(Amrit Campus, 2024-09-09) Sabina Thokar; Dr. Laxmi Joshi ShresthaAvailable Full TextItem Native and Invasive Plants in Some Selected Habitats of Dhangadhi Sub-Metropolitan City, Far West Nepal(Amrit Campus, 2024-04-04) Roshni Bhatta; Prof. Dr. Bipana AcharyaAvailable Full TextItem Heavy Metal Accumulation in Some Plants at Butwal Sub-Metropolitan City, Nepal(Amrit Campus, 2024-07-30) Ramchandra Adhikari; Dr. Laxmi Joshi ShresthaAvailable Full TextItem Population Status and Harvest Practice Of Nardostachys Jatamansi (D.Don) Dc. in Jumla District, Karnali, Nepal(Amrit Campus, 2024-05-17) Priscilla Gautam; Dr. Baburam PoudelAvailable Full TextItem Prevalence Of Ectoparasites (Lice) Among Domestic Animals (Buffalo, Goat and Pig) of Khaniyabas Rural Municipality-3, Dhading District, Nepal(Amrit Campus, 2024-09-21) Bina Tamang; Dipak GuptaAvailable Full TextItem Distribution Pattern, Morphology and Anatomy of Taxus Mairei (Lemée & Lév.) S.Y. Hu In Nepal(Amrit Campus, 2024-08-28) Pramila Dhukhwa; Prof. Dr. Lokesh Ratna ShakyaAvailable Full TextItem 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.