MPhil Thesis

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Evaluation of antifungal activities of extracts of some medicinal plants on Neurospora Crassa
(University of Dhaka, 2016-01-10) Sultana, Razia
Antifungal activity was investigated using the leaf extracts of five different medicinal plants namely, Ocimum sanctum Linn., Coccinia cordifolia (Linn.) Cogn, Andrographis paniculata (Burm. f.) Wall., Centella asiatica (Linn.) Urban., Azadirachta indica A. Juss. against two fungi Neurospora crassa and Helminthosporium oryzae. The in vitro study revealed the presence of antifungal activity against Neurospora crassa in the leaf extracts of all the plants used during the study. The non sterilized leaf extracts was more effective than sterilized leaf extracts. The antifungal effect of these plant extracts enhanced gradually with the application of increased concentration and best antifungal activity was observed in the leaf extracts of Azadirachta indica A. Juss. as compared to all the tested plants. It inhibited the radial growth of both Neurospora crassa and Helminthosporium oryzae at 25% concentration. Antifungal activity was observed in the proteins present in the proteins of third fraction after (NH4)2SO4 gradient centrifugation and 200 µg of the total proteins of this fraction was found effective in controlling the fungal growth in vitro. Two proteins of the third fraction e.g., 40 and 37 kDa were found to be effective to control the fungal radial growth of both the Neurospora crassa and Helminthosporium oryzae.
Comparative eco- physiology of two cultivars of wheat (triticum aestivum cv. bari 26 and cv. pradip) in relation to soil moisture and salinity
(University of Dhaka, 2016-01-13) Hafiz, Shamima
Experiment has been done with two cultivars of wheat cv Bari 24 and Bari 26 in relation to salinity and soil moisture to study the growth, yield and water relations. Salinity experiment was done in the laboratory in Petri dishes. Two cultivars of wheat, Triticum asetivum (cv. Bari-24 (Pradip) and cv. Bari- 26) were grown in the different concentrations of sodium chloride solution and the seedling growth was observed. Shoot and root length of the seedlings of both cultivars of wheat showed a significant (P= 0.05) decrease at the highest salinity treatment but at the lowest salinity treatment i.e. at 0.05 M NaCl both shoot and root length increased. It is suggested that the growth of both cultivars of wheat seedling is favoured by low NaCl salinity. Seeds of two cultivars of Triticum aestivum (cv. Bari- 24 and cv. Bari- 26) were grown in the field under wet (watering everyday) and dry (watered once in a week) treatments. Six harvests were done with an interval of 7 days. Growth analysis from successive harvest of plants showed that early pattern of growth was influenced by moderate restriction in the availability of soil water and was associated with marked shift in the allocation of growth resources in favour of root development. Plant height, total dry weight, shoot and root dry weight, relative growth rate, and root: shoot ratio were analyzed after every harvest. In wet treatment, the number of lateral roots showed luxurious growth from those of dry treatment. Root and shoot length of both cultivars was significantly (P= 0.05) higher than dry treatment. Apart from total dry weight, the root and shoot dry weights were also higher in wet treatment than that of dry treatment. Relative growth rate (RGR) did not show significant difference between wet and dry treatments. Root/ Shoot ratio of both cultivars in all treatments from 3rd harvest onward showed an increasing tendency. Spike length and weight were maximum in cv. Bari 24 under wet condition and minimum was in cv. Bari 26. The maximum value of Flag leaf area was found in cv. Bari-26 in wet treatment and lowest was in cv. Bari 24 in dry condition. The area of flag leaf did not show any significant difference (P= 0.05) between the treatments but an increasing tendency of flag leaf area was noted under wet condition. Tissue water relations in wet and dry treatments were examined in leaf material collected from the field, with a view to obtaining comparative data on the mechanism of adaptation to drought. The relative water content was significantly (P=0.05) lower in cv. Bari 24 under wet condition than dry treatment and was highest in cv. Bari 26 in dry treatment plants. Wet treatment plants showed the maximum rate of loss of water, while dry treatment plants showed the lowest. The plants of these two cultivars of wheat showed a significant difference in their growth and yield in relation to soil moisture.
Aeromycoflora of Dhaka city, Bangladesh
(University of Dhaka, 2016-01-17) Sultana, Tania
The air influences every aspect of life and the activities of organisms affect the air. Sources of air borne microorganisms are everywhere. They are in food, water, on utensils and on bed sheets. The indoor and outdoor air is an important source of aeroallergens and pathogens. During the present investigation, monthly sampling of air borne mycoflora of Dhaka Metropolitan City, during February 2013 to January 2014 was recorded. The fungal colonies developed in PDA media were isolated from five different locations in the morning and evening in monthly intervals. The total number of counted fungal colonies were 6648 out of which in the morning was 3268 and in the evening it was 3380 and 156 colonies were sterile mycelia. The sampling sites were Sher-e Bangla Agricultural University, Gulistan, Dhaka Medical College, Sadarghat and DOHS, Mohakhali. The qualitative nature of the mycoflora, their mean, standard deviation, percent frequency and correlations to the total mycoflora, monthly periodicity have been described in this investigation. In this study, fifteen genera have been recorded viz. Alternaria, Arthrinium, Aspergillus, Bipolaris, Chaetomium, Cladosporium, Colletotrichum, Curvularia, Fusarium, Nigrospora, Penicillium, Pestalotia, Rhizopus, Syncephalastrum and Trichoderma under the class Ascomycetes, Zygomycetes and Deuteromycetes. Local fluctuations of the air borne fungi in relation to some meteorological parameters were also studied. The three most dominant fungal species were Aspergillus, Cladosporium and Penicillium contributing 30.71, 18.10 and 12.79% in the evening and in the morning it was 28.82, 15.78 and 11.53% in twelve months counting of the total colonies, respectively. Aspergillus was found in the highest frequency in the present investigation among the identified genera. In the present study Cladosporium was found 2nd position in term of its percent frequency. Maximum number of fungal colonies were found in Gulistan and Sadarghat in the morning and evening. During the twelve months investigation maximum fungal colonies were found in August and September as all the climatic factors were favorable for the fungal growth, their dispersal and survival. Among the fungi, found in the present investigation Alternaria, Aspergillus, Chaetomium, Cladosporium, Curvularia, Fusarium, Penicillium and Rhizopus were reported as pathogenic to plants and/or human and strongly allergenic to human. Bipolaris, Colletotrichum, and Pestalotia were reported as only plant pathogens. The present study contributes to our knowledge of air borne spores in the Dhaka City. Regular monitoring of air borne fungi can be helpful in the prevention of fungal allergic diseases in the city.
Development of in vitro plant regeneration system and agrobacterium–mediated genetic transformation in Mungbean (Vigna radiata (L.) wilczeck)
(University of Dhaka, 2017-11-01) Begum, Setara
An efficient protocol has been developed for Agrobacterium-mediated genetic transformation of two important mungbean (Vigna radiata (L.) Wilczeck) varieties cultivated in Bangladesh, namely, Binamoog-5 and BARI mung-6. Prior to transformation an efficient in vitro regeneration protocol was developed for these two mungbean varieties. Cotyledonary node, shoot tip and cotyledone attached decapitated embryo were used as explants for direct regeneration of shoot. MS medium with various combinations and concentrations of BAP, Kn and NAA were used for direct regeneration of shoots. MS medium supplemented with 10.0 μM BAP and 0.5 μM NAA was found to be the best towards the development of highest number of multiple shoots. Full strength of MS medium supplemented with 2.0 μM IBA was found to be the most effective for healthy root induction from the regenerated excised shoots. Following root induction the in vitro regenerated plantlets were successfully transplanted to soil. Transformation experiments with cotyledone attached decapitated embryo, cotyledonary node and decapitated embryo explants were conducted using Agrobacterium tumefaciens strain, namely, LBA4404 harboring the binary plasmid pBI121 conferring GUS (β-glucuronidase) and nptII (neomycin phosphotransferase II) genes. Transformation experiments were monitored through GUS histochemical assay since the strain of Agrobacterium contained GUS gene. Different factors influencing successful transformation such as, density of bacterial suspension, incubation and co-cultivation periods were optimized. Maximum responses towards transformation were obtained with bacterial suspension having an optical density of 0.56 at 600 nm. Moreover, 30 minutes of incubation period followed by 72 hours of co-cultivation period were found to be the most effective towards transformation as determined by transient GUS assay. Selection of transformed shoots was carried out using different concentrations of kanamycin as the Agrobacterium strain contained nptII gene. Transformed shoots were selected using 150 mg/l kanamycin. The survival of green shoots on the optimum selection medium indicated the production of transformed shoots. Stable expression of the GUS gene was detected in various parts of transformed plantlets. Putatively transformed shoots were rooted on full strength of MS medium containing 2.0 μM IBA and 100 mg/l ticrecilin. Rooted transformed plantlets were successfully transferred to soil. Genomic DNA was isolated from the putatively transformed mungbean shoots and stable integration of GUS and nptII genes was confirmed by polymerase chain reaction (PCR) analysis.
Effects of salinity on the nodulation in lentil (Lens Culinaris Medik.) and the diversity of its compatible nitrogen-fixing Rhizobium
(University of Dhaka, 2019-10-07) Ferdous, Jannatul
Salinity in soil causes risk for growth, nodulation and biological nitrogen fixation in legumes. Biological nitrogen fixation occurs through the symbiotic association between legumes and Rhizobium. Legume-rhizobia symbiosis and the efficiency of biological nitrogen fixation are influenced by a number of environmental factors including salinity. This study was carried out to evaluate the effects of salinity on the growth parameters and nodulation of lentil plants (Lens culinaris Medik.) at various NaCl concentrations. Seeds of lentil were sown in the experimental plots at the Botanical Garden of University of Dhaka. Each of the four salt treatments (0 mM, 50 mM, 100 mM and 200 mM NaCl) was applied in three replicate plots. Treatments were applied once in every seven days. The size of each plot was 0.0625 m2. Plants were grown for 2 months in the field. Shoot and root growth parameters including length, fresh and dry weight of shoot and root, leaf chlorophyll content, root to shoot ratio, root nodule number and proline content of leaf were compared among the different salt treatments. This study also examined the effects of soil salinity on the number of bacterial colonies obtained from root nodules, rhizosphere soil and bulk soil of lentil plants. The suspensions of root nodules were cultured in the nutrient agar medium and then bacterial colonies were isolated and counted. Bacterial DNA were isolated from pure isolates of bacterial colonies obtained from soils collected from different areas of Bangladesh. PCR amplification using bacterial DNA samples as template was done by targeting 16s rRNA gene. After purified PCR product was achieved, the sequences of different strains of rhizobia were identified by using NCBI blast. Phylogenetic tree was also constructed based on the 16S rRNA sequencing of isolated bacteria. In comparison to control (0 mM), shoot height, root fresh weight, number of nodules and chlorophyll content of leaf decreased with the increase of salt treatment although no significant difference appeared. Proline concentration of leaf of lentil increased significantly with the increase of salt concentrations. Number of bacterial colony increased with the increase of salt concentration. Compared to bulk soil, rhizosphere soil showed higher number of bacterial colonies. The result thus indicates that soil salinity can influence bacteria associated with the root nodule and rhizosphere of lentil plants. The clusters of phylogenetic tree indicated the genetic diversity of rhizobia associated with root nodules collected from different sites. Result of this study is expected to provide valuable information and may be useful to the researchers as well as the policy makers of both Government organizations and Non-government organizations for formulating appropriate policy for widespread cultivation of lentil in Bangladesh.
Mycoflora of maize (Zea Mays L.) seeds in different storage conditions and their management
(University of Dhaka, 2019-10-10) Sadia, Ummay
An investigation was carried out to find the association of fungi with different varieties of maize seeds in storage during the period of 2011-2015. Samples were collected from Bangladesh Agricultural Research Institute (BARI), Joydebpur, Gazipur. Fungi associated with seeds of maize were isolated following “Blotter” and “Tissue planting” method. A total of seven fungi were isolated from the seeds of maize in storage. The isolated fungi were Aspergillus flavus, A. fumigatus, A. niger, Curvularia lunata, Fusarium sp., Penicillium sp. and Rhizopus stolonifer. The frequency percentage of association of Aspergillus niger isolated from maize seeds was higher than any other fungi. Pathogenic potentiality of the isolated fungi was carried out following seed inoculating technique. Among the isolated fungi C. lunata and Fusarium sp. were found to be pathogenic to the maize seeds. Five fungicides viz., Bavistin 50 WP, Dithane M-45, Greengel 72 WP, Ridomil MZ Gold and Tall 250 EC were selected to evaluate their in vitro efficacy at different concentrations against the test fungi. In this study, out of five fungicides Tall 250 EC showed best inhibiting effect on the test fungi followed by Bavistin 50 WP, Dithane M-45, Greengel 72 WP and Ridomil MZ Gold. Five plants extracts viz., Azadirachta indica A. Juss, Allium sativum L., Citrus medica L., Datura metel L. and Tagetes erecta L. were selected to evaluate their in vitro fungitoxicity at 5, 10 and 20% concentrations against test fungi. In this study, Allium sativum and Datura metel showed 100% radial growth inhibition of A. fumigatus at 20% concentration. The present investigation suggests that out of five fungicides, Tall 250 EC can be used as best inhibiting chemical agent against the fungi associated with different maize varieties. Out of five plant extracts, Allium sativum identified as best botanicals for further investigation against the fungi associated with different maize varieties.
Effects of Eucalyptus Plantation on the Physico-Chemical Properties and Litter Decomposition Processes in Soil
(University of Dhaka, 2020-03-18) Sarker, Protika
Plantation of Eucalyptus has been increasing worldwide for the multiple benefits including fast growth, massive biomass production and quick economic returns. However, plantation with Eucalyptus has created debate from ecological concerns such as loss of biodiversity and degradation of soil quality including loss of soil water and nutrients. The general aim of the research was to investigate the ecological effects of plantation with the introduced species Eucalyptus to improve understanding about the plantation, afforestation and management of sustainable forestry program by using this tree species in Bangladesh. Soil and plant materials were collected from different sites such as Tangail, Dinajpur and Dhaka where there were plantations of this species was done along with other tree species such as Acacia (Acacia auriculiformis), Jarul (Lagerstroemia speciosa) and teak (Tectona grandis). Soil was collected at different distance from the tree trunk and depths along the soil column in order to study the physical and chemical properties. At the Madhupur site where Eucalyptus plantation was done beside the plantation with Acacia, pH was significantly (P = 0.0399) affected by depth but not by plantation and their interactions. Electrical conductivity was significantly affected by plantation (P = 0.0001) but not by depth and their interactions. Total P (%) was significantly affected by both plantation (P = 0.0310) and depth (P = 0.0211) but not by their interactions. At the Dinajpur site where Eucalyptus plantation was done beside the plantation with Jarul. Moisture content (P = 0.0001) and organic carbon were significantly (P = 0.03) affected by plantation but not by depth and their interactions. Soil pH was significantly affected by both plantation (P = 0.0001) and depth (P = 0.0029) but not by their interactions. Total phosphorous was significantly affected by both plantation (P = 0.0015) and depth (P = 0.0241) but not by their interactions. N:P was significantly affected by only plantation(P = 0.0494). At the Dr. Muhammad Shahidullah Hall Campus site where Eucalyptus plantation was done beside the plantation of teak, three-way ANOVA statistics showed that pH value was significantly affected by plantation (P = 0214), distance (P = 0.0001) and depth (P = 0.0103) but not by their interactions. Organic carbon content was significantly affected only by the interaction of distance and depth (P = 0.0457) but not by other factors such as plantation, distance and depth. Total P (%) (P = 0.0001) and N:P (P = 0.0047) were significantly affected only by plantation. Litter decomposition study conducted for 12 months showed that mass loss rate of Mahagony (Swetenia mahogoni) was significantly affected by litter type (P = 0.023) and time (P = 0.075) but not by their interactions. In case of teak, mass loss rate was significantly affected by time (P = 0.002) and between time and litter type (P = 0.017) but not by litter type. In case of Axonopus (Axonopus compressus), highly significant (P = 0.001) difference was found between time and litter type (P = 0.035) but not in their interactions. Soil N content was significantly (P = 0.000) affected only by time in teak and only by interaction between time and litter type (P = 0.019) in Mahogony. Litter type effects on N release was absent for each species. Overall, the results of the present study indicated that plantation with Eucalyptus might had potential influence in altering decomposition rate of an ecosystem through mixing of its litter with that of the other plant pecies.
ETHNOMEDICINAL PLANTS FOR THE MANAGEMENT OF CARDIOVASCULAR DISEASES IN BANGLADESH
(©University of Dhaka, 2023-11-15) JUTHI, TAHMINA SULTANA
The use of ethnomedicinal plants for curing ailments has been gaining popularity all over the world because of simplicity in the treatment system, affordability to the local people, less expensive, available in nature, and effectiveness in chronic diseases. Currently, the local knowledge of ethnomedicinal plants is in danger because of inadequate scientific documentation. The present study aimed to record and validate the ethnomedicinal knowledge used by the local people for the management of cardiovascular diseases (CVDs). The ethnomedicinal data were collected from the selected districts of Bangladesh during the year 2018-2020 using modern ethnobotanical survey methods. During the survey, a total number of 300 local informants including 67% males and 33% of females were interviewed which were mostly farmers and housewives. The study had resulted in recording a total of 131 ethnomedicinal plant species under 61 families. The recorded plant species had been used by the people for the treatment of five (5) diseases categories related to the Cardiac problem through 114 formularies. Habit analyses of medicinal plant species showed that herbs (41%) were the leading medicinal plants followed by trees (33%), shrubs (19%), and climbers (7%). Leaves were the most regularly used plant part, with 35% application in traditional medicinal recipes, followed by fruit (26%), seed (12%), root (6%), bark (5%), whole plant (5%), flower (4%), rhizome (2%), tuber (1%), bulb (1%), latex (1%), and stem (1%). The most common medicinal families were Fabaceae, Amaranthaceae, Asteraceae, Cucurbitaceae, and Apocynaceae. Among the diseases categories highest (Fic) value was obtained in Cardiac complaints followed by Blood purifier, Chest pain, High blood pressure, and Antioxidant. The cardiac complaints were managed by a total of 80 medicinal plant species. Among the medicinal plants, the most cited were Phyllanthus emblica L., Allium sativum L., Terminalia arjuna (Roxb. Ex DC.) Wight & Arn., Achyranthes aspera L., Terminalia chebula Retz, Allium cepa L. In the blood purifier category, 76 species were used and Phyllanthus emblica L., Terminalia chebula Retz, Allium cepa L., were most cited. In the chest pain category, 20 species were used and the most cited were Terminalia arjuna (Roxb. Ex DC.) Wight & Arn., Achyranthes aspera L. In the High blood pressure category, 39 species were used and the most cited were Phyllanthus emblica L., Allium sativum L., Terminalia arjuna (Roxb. Ex DC.) Wight & Arn., Terminalia chebula Retz, Allium cepa L. In the Antioxidant category, 36 species were used and Phyllanthus emblica L, was the most cited plant. Among the 131 plant species, 45 species were scored 100% fidelity level as culturally important plant species. The record of 131 ethnomedicinal plant species with diverse use patterns reflected the traditional knowledge richness in the study area. Among the ethnomedicinal plants, 10 plant species including Phyllanthus emblica L., Allium sativum L, Terminalia arjuna (Roxb. Ex DC.) Wight & Arn, Achyranthes aspera L, Terminalia chebula Retz., Allium cepa L, Adhatoda zeylanica Nees, Cinnamomum tamala Nees & Eberm, Cajanus cajan (L.) Millsp, Ipomoea aquatic Forssk, were cited maximum times by the local people. These species had been used frequently in the study area for primary healthcare also. Among the ten plant species, local use of three species named Allium cepa L, Cinnamomum tamala Nees & Eberm, and Ipomoea aquatica Forssk had been studied because of identifying the effectiveness in chronic diseases. Methanolic extract of the leaf of A. cepa, I. aquatica, and C. tamala showed 22.24 %, 28.96 %, and 58.99 % lysis of the clot respectively by using 100 µl of streptokinase as a positive thrombolytic control (30,000 I.U) on blood clots and distilled water as a negative control. It showed that the addition of 100 µl of streptokinase as a positive thrombolytic control (30000 I.U) to blood clots with 90 min of incubation at 37°C showed 68.79 % of clot lysis and distilled water was treated as a negative non-thrombolytic control, which exhibited negligible percentages of lysis of clots (2.04%). Of the three plants, C. tamala showed the highest thrombolytic activity for clot lysis rather than I. aquatica and A. cepa plants. The results were very promising. Further research is very necessary to isolate the chemicals responsible for thrombolytic potentials. Based on observations and local people perception, most cited species named Achyranthes aspera L., Cajanus cajan (L.) Millsp., Andrographis paniculata Nees., Aquilaria malaccensis Lam., Dioscorea alata L., and Rauvolfia serpentina (L.) Benth. ex Kurz., were found very rare in the habitat and were also in danger because of anthropogenic pressure, deforestation, lack of knowledge about plants, and mismanagement of plantations in the study area. Based on the present study, it may be concluded that A. cepa, I. aquatica, and C. tamala might be used as traditional healing purposes of CVDs. Moreover, further animal study will prove the scientific validation of their uses. Management efforts should be provided to save A. cepa, I. aquatica, and C. tamala plants from the extinction in nature.
The effect of salinity on inorganic nutrition of chickpea and its correlation with anatomical and biochemical changes
(© University of Dhaka, 2025-04-24) Mariam, Hasina
Phytohormone directed transport of ions in rice (Oryza Sativa L.) seedlings
(© University of Dhaka, 2025-04-24) Ahmed, Shahana
Induction of mutation with botano-chemicals in Neurospora crassa, classification, characterization and genetic studies of induced mutants
(© University of Dhaka, 2025-04-24) Rahman, Md. Siddiqur
Taxonomic study of fungi associated with botrytis grey mould (bgm) disease of chickpea (Cicer arietinum L.)
(© University of Dhaka, 2025-04-24) Sultana, Razia
Induction of mutants in Neurospora crassa and its genetical and biochemical investigation
(© University of Dhaka, 2025-04-24) Begum, Mamtaz
Screening of probiotic organisms for their Antagonistic activity and nutritional potentiality
(© University of Dhaka, 2025-04-24) Zuha, Sanjida Binte
Removal of environmental pollutants using Neurospora crassa Biomass
(© University of Dhaka, 2025-04-27) Jahan, Mahbuba Akhter