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University of Agricultural Sciences, Bengaluru

University of Agricultural Sciences Bangalore, a premier institution of agricultural education and research in the country, began as a small agricultural research farm in 1899 on 30 acres of land donated by Her Excellency Maharani Kempa Nanjammanni Vani Vilasa Sannidhiyavaru, the Regent of Mysore and appointed Dr. Lehmann, German Scientist to initiate research on soil crop response with a Laboratory in the Directorate of Agriculture. Later under the initiative of the Dewan of Mysore Sir M. Vishweshwaraiah, the Mysore Agriculture Residential School was established in 1913 at Hebbal which offered Licentiate in Agriculture and later offered a diploma programme in agriculture during 1920. The School was upgraded to Agriculture Collegein 1946 which offered four year degree programs in Agriculture. The Government of Mysore headed by Sri. S. Nijalingappa, the then Chief Minister, established the University of Agricultural Sciences on the pattern of Land Grant College system of USA and the University of Agricultural Sciences Act No. 22 was passed in Legislative Assembly in 1963. Dr. Zakir Hussain, the Vice President of India inaugurated the University on 21st August 1964.

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2020 - 202324
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Subject: Agricultural Microbiology × End date: 2023 × Start date: 2020 × Type: Thesis × Thesis Type: Ph.D ×
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Now showing 1 - 9 of 24
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    ThesisItemEmbargo
    BIOEFFICACY OF ENTOMOPATHOGENIC FUNGI AGAINST MAJOR INSECT PESTS OF GERBERA (Gerbera jamesonii Bolus ex. Hooker F.) UNDER POLYHOUSE CONDITIONS
    (University of Agricultural Sciences, Bangalore, 2023-05-31) PRAVEEN RANADEV; K. NAGARAJU
    The bioefficacy of entomopathogenic fungi against major insect pests of gerbera was studied under polyhouse conditions. Out of the 81 fungal isolates isolated from two agro-climatic zones of Karnataka, India, 16 isolates showed insecticidal activity and were identified as Metarhizium spp. Beauveria spp. Aspergillus spp. Lecanicillium spp. Isaria spp. and Hirsutella spp. Additionally, the 16 isolates were examined for cuticle degrading enzyme activity, namely chitinase, protease and lipase. The enzymes activity of Beauveria sp. and Lecanicillium sp. ranged between 0.87-1.21 U/ml, 0.1-0.32 U/mL, and 0.28-0.43 U/mL, respectively. The leaf discs treated with Lecanicillium sp. (ENPF-24 & ENPF-41), Beauveria (ENPF-60) and Hirsutella sp. (ENPF-58) showed significantly higher mortality rate in test insects (aphids, thrips, mites and whitefly). The LC50 and LT50 were determined by probit analysis and the lowest LC50 (9.4×104, 1.5×105 and 1.5×105 conidia/mL) and LT50 (5.7, 5.89, and 5.51 days) were recorded from Lecanicillium sp. (ENPF-41). Sabouraud’s dextrose was found to be the best medium to produce entomopathogenic isolates. Further, Among the agro-wastes, the isolates produced significantly higher conidial in sorghum grains fortified with 10% molasses, followed by the treatment, 25% paddy husk + 25% Bagasse + 25% PMS + 25% Crushed Sorghum grains + 10% molasses. Subsequently, six virulent strains of entomopathogenic fungi were molecularly identified as Beauveria bassiana, Lecanicillium lecanii, Isaria fumosorosea and Hirsutella thompsonii. Under polyhouse conditions, the application of biocontrol agents reduced the gerbera pest population by 35-50%. Native entomopathogenic fungal isolates performed better than reference strains.
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    DEVELOPMENT OF MICROBIAL CONSORTIUM FOR AGRICULTURAL CROP RESIDUE MANAGEMENT
    (University of Agricultural Sciences, Bangalore, 2023-03-30) JAGADEESH, U.; Muthuraju, R.
    A total of 173 microorganisms were isolated and qualitatively screened for lignocellulolytic activities and further screened based on quantitative and number of lignocellulolytic enzyme production like FPase, CMCase, β-glucosidase, Xylanase, Laccase, Mnp and Lip. The promising lignocellulolytic isolates viz. UASFW, UASFK2, UASBW1 and UASAP2 were selected and were identified as Phanerochaete chrysosporium UASBLCF_01, Purpureocillium lilacinum UASBLCF_02, Bacillus inaquosorum UASBLCB_03 and Streptomyces viridosporus UASBLCA_04, respectively at genomic level with compatibility study. In an in-vitro study using these isolates a consortium was developed based on their degradation potential using paddy straw, sugarcane trash and maize stover as substrates. The developed lignocellulolytic consortium showed highest degradation potential, steady decrease in Neutral Detergent Fiber (NDF) and Acid Detergent Fiber (ADF) compared to the control. The C: N declined to 18.86 in paddy straw, 16.98 in maize stover and 22.70 in sugarcane trash at 90 days after composting. Scanning electron microscope analysis showed modification in the surface structure of the degraded material. Further, lignocelluloytic consortium was tested for its degradation potential when amended with cow dung, FYM @ 10%, urea (@ 2% & 4%), human urine (1:1 & 2:1 dilution) using paddy straw, sugarcane trash and maize stover substrates. The results revealed that, in all substrates amended with cow dung @10%, FYM and urea @4% (T6) showed faster degradation and found statically on par when substrates were amended with urea @2% (T5), human urine of dilution 1:1 (T7) and 1:2 (T8) where cow dung and FYM were common. Hence, urea @2% and human urine @1:2 dilution were optimized for large scale compost production of all the three substrates along with cow dung @10%, FYM @10% and consortia. In a field study, 100% RDF + urea enriched paddy straw compost (T4) produced better baby corn growth and yield and improved soil biological parameters.
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    LACTIC ACID BACTERIAL FORMULATIONS FOR REDUCING POST-HARVEST SPOILAGE IN ONION (Allium cepa L)
    (University of Agricultural Sciences, Bangalore, 2023-03-02) BHARATH KUMAR, N.; Suvarna V. Chavannavar
    Lactic acid bacteria are well known for their antimicrobial properties and are considered generally recognized as safe (GRAS) microorganisms. The spoiled onion bulbs were screened and isolated LA bacteria (26), spoilage bacteria (15) and six spoilage fungal isolates. The LA bacterial isolates were tested for antimicrobial potential using agar well diffusion, plug diffusion and fungal biomass method against spoilage isolates. These isolates inhibited bacteria with an inhibition zone from 0.00 to 21.37 cm2 and fungal colony growth from 0.00 to 53.90 cm2. The efficient LA bacterial isolates (two) were identified as Levilactobacillus brevis; the potent spoilage bacteria as Paenibacillus polymyxa, Bacillus spizizenii and B. subtilis; spoilage fungi as Aspergillus tamari and A. welwitschiae. The GC-MS analysis revealed the presence of 11 and eight antimicrobial compounds in cell-free supernatant of Levilactobacillus brevis UASBMIC_001 and L brevis UASBMIC_002 respectively. In situ bio-preservation of onion using pinprick method extended the shelf-life of onion to 28 days. Polyurethane foam cubes and sawdust bedding material supported the viability of LA bacterial consortium (16.66 x 108 CFU /g) and (128.66 x 103 CFU /g) up to 45th day, respectively. The LA bacterial consortium inoculated with sawdust was able to increase the onion shelf-life for 28 days during storage. Thus, LA bacterial consortium are able to extend the shelf life of onion and polyurethane foam cubes can be effectively used as a carrier material under room temperature. The sterilized sawdust can be used as bedding material for onions as they maintain a viable population of LA bacteria
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    ThesisItemOpen Access
    DEVELOPMENT OF NUTRACEUTICAL BEVERAGE FROM JACKFRUIT AND BEET ROOT JUICES USING YEAST AND LACTIC ACID BACTERIA AND THEIR CHARACTERIZATION
    (University of Agricultural Sciences, Bangalore, 2023-02-11) Ashiwini, G.; B. NARAYANASWAMY
    Jackfruit and beet root are exceptional fruit and vegetable crop loaded with vitamins and minerals. Naturally associated yeasts and lactic acid bacteria (LAB) were isolated from jackfruit and beet root juices. Probiotic activity of the yeasts and LAB isolates were evaluated. Yeast isolates JCVY- I and BDVY-I exhibited maximum pH (1.5 to 8.5) and bile salt tolerance (up to 2.0 %). JCVY-I produced highest zone of inhibition against antibiotics cycloheximide (30μg/mL) and fluconazole (30μg/mL) i.e., 18.67 mm and 21.33 mm respectively. JCVY- I showed antimicrobial activity against Escherichia coli and Staphylococcus aureus with highest distance of inhibition of 17.67 mm and 15.33 mm respectively. LAB isolates JCVL – II and BDVL – III were tolerant to pH (1.5 to 8.5) and bile salts (up to 2.0 %). They were moderately resistant to antibiotics. JCVL- II produced highest zone of inhibition against Escherichia coli (25.33 mm) and Staphylococcus aureus (18.67 mm). JCVY-I and BDVY- I were molecularly identified as Pichia kudriavzevii and Wickerhamomyces annamola respectively. JCVL- II and BDVY- III isolates were molecularly identified as Lactiplantibacillus plantarum and Levilactobacillus brevis respectively. These efficient yeast and LAB strains were used for development of nutraceutical beverage. Storage period of 60 days was maximum for maintaining the viability of cultures. Treatments having mixed juice + Pichia kudriavzevii + 4 % honey + 7.5 % whey (ambient temperature) and mixed juice + Lactiplantibacillus plantarum + 4 % honey + 7.5 % whey (refrigerated temperature) scored highest overall acceptability of 15.60 and 15.31 out of 20 respectively. February,
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    PROSPECTING ENDOPHYTIC FUNGI FOR IMPARTING ABIOTIC STRESS TOLERANCE IN MUNG BEAN [Vigna radiata (L.) R. Wilczek] AND RICE (Oryza sativa L.)
    (2023-02-07) ARUNKUMAR G. PANDIT; N. EARANNA
    Endophytes are microorganisms that complete their life cycle inside living plant tissue without causing any signs of diseases. They improve plant growth and impart tolerance to biotic and abiotic stresses. In this study, 48 fungal endophytes isolated from plants of North Western Himalayan cold desert were screened against drought and salinity stresses using poly ethylene glycol (8000MW) and NaCl respectively for mung bean (KKM-3) and rice (IR-64). Of which, five isolates, P-82, P-39, P-31, P-10 and Z-24) in Mung bean and P-82, P-31, Z-24, Z-22 and Z-13 in rice showed drought tolerance in-vitro. They were identified as Ulocladium sp. (P-82), Fusarium avenaceum (P-39), Chaetomium sp. (P-31), Fusarium tricinctum (P-10), Fusarium acuminatum (Z-24) and Subramaniula flavipila (Z-13). Out of six isolates, the Fusarium avenaceum and Chaetomium sp. significantly enhanced the growth of Mung bean and the F. acuminatum increased the growth of rice seedlings under drought stress. Further, the 48 isolates screened for salt tolerance, only four isolates (P-82, P-39, P-31 and P-10) showed salt stress tolerance in both the crops. Of which, the F. avenaceum (P-39) showed significantly increased growth of mung bean and rice at LC50 value of NaCl concentration. Inoculation of these endophytes increased the growth and yield of stress induced (drought and salinity) mung bean and rice plants under greenhouse conditions. The endophyte treated plants also increased the photosynthetic pigments, relative water content, proline and growth hormone production compared to uninoculated plants under stress. Thus, the study revealed that the fungal endophytes can mitigate the abiotic stresses and improve the growth and yield of Mung bean and Rice.
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    ThesisItemOpen Access
    EXPLORING BIOCONTROL AND GROWTH PROMOTION POTENTIAL OF ACTINOBACTERIA FROM NATURAL ECOSYSTEMS
    (University of Agricultural Sciences, Bangalore, 2021-12-29) BINDUSHREE, C.; M. K. SHIVAPRAKASH
    Actinobacteria, a Gram positive bacteria and a major source of most of the antibiotics being used, are also being explored as plant growth promoting and biocontrol agent for various crop plants. When compared with other groups of microorganism, actinobacteria are relatively less explored with agricultural perspective. The present study was conducted with a view to isolate and screen actinobacteria from natural ecosystems and evaluate their potential for plant growth promoting and biocontrol activity. A total of 120 actinobacterial isolates were isolated from rhizospheric soil (n=4), forest soil (n=39) and compost (n=40). The functional potentialities of the isolates recorded were phosphate solubilization, siderophore, IAA, gibberellic acid, cytokinin and ammonia production. The SA12 isolate of rhizospheric soil, was found to be highest producer of IAA (63.33 μg/mL) and gibberallic acid (40.53μg/mL). The FA13 isolate showed highest cytokinin production (30.16 μg/mL). The SA12 exhibited maximum phosphate solubilization activity (32.87 mg/mL), while the isolate SA12 and CA18 showed maximum ammonia production (32.87 mg/mL 30.05 and mg/mL). Forty two isolates out of 120 displayed antagonistic activity against different plant pathogenic fungi (Fusarium oxysporum, Pythium sp., Sclerotium rolfsii and Alternaria sp) and thirty actinobacterial isolates displayed antagonistic activity against plant pathogenic bacteria Xanthomonas campestris and Ralstonia solanacearum. The results indicated that the isolates, FA15, FA13, SA12, CA18 and CA4 were prominent in inhibiting the growth of all the pathogens and were selected further screening for biocontrol efficiency and seedling vigour in solanaceous vegetable crops under greenhouse conditions. The treatment received inoculum of consortium of selected actinobacterial isolates had shown significant biocontrol efficiency against the damping off, wilt pathogens and seedling vigour index in seeding tray and pot culture experiments.
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    Development of Cobalamin rich Nutraceutical product using Propionibacterium freudenreichii
    (University of Agricultural Sciences, Bangalore, 2022-09-05) HARISH KUMAR, K.; Suvarna, V. Chavannavar
    The vitamin B12, cobalamin is a water soluble vitamin is needed for red blood cell synthesis and nervous system functioning. The animal based foods are the sources of cobalamin and plant foods lack cobalamin. Archaea and eubacteria are capable of cobalamin synthesis. Propionibacterium freudenreichii is the only food bacterium able to synthesize stable quantities of cobalamin. Hence, attempted to isolate Propionibacterium freudenreichii, identify using molecular methods, screening isolates for probiotic characteristics, mutants isolation, vitamin assay, auxanographic patterns, developing vitamin B12 enriched fermented food as an alternative source of vitamin B12. The isolation of dairy propionibacteria from milk, curd, cheese, pickle and silage was done using Yeast Extract Lactone Agar medium. The isolates were subjected to biochemical and molecular characterization and cheese isolate was identified as Propionibacterium freudenreichii using 16S rRNA characterization. It was exposed to UV radiations to get UV resistant mutants (PFM1-10). The auxanography, antibiotic sensitivity, haemolytic activity, vitamin B12 synthesizing ability of mutants and wild strain were studied. The wild strain could synthesize the highest vitamin B12 (15.23 μg 100 mL-1). Mushrooms were cultivated under in-vitro conditions along with vitamin B12 precursor and P. fruedenreichii and it was found that the treated mushrooms could not synthesize vitamin B12. Further, attempts were made to develop milk-based fermented beverage using starter inocula of home-made curd, Propionibacterium freudenreichii, Lactobacillus acidophilus, P. freudenreichii + L. acidophilus and yoghurt as treatments. The highest cobalamin production (10.37 μg 100 mL-1) and sensory acceptability score (8.15 of 9) was found in the treatment inoculated with Propionibacterium freudenreichii alone. The recommended dietary allowance for vitamin B12 is 2.4 μg and this can be met by consumption of 23 mL of developed milk product.
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    HARNESSING THE POTENTIAL OF QUORUM QUENCHING BACTERIA FOR THE CONTROL OF MULTIDRUG RESISTANT PHYTOPATHOGENIC BACTERIA
    (University of Agricultural Sciences, Bangalore, 2022-12-31) SOWMIYA, K.; Tamil Vendan, K
    Pathogenicity of bacteria by biofilm formation, antibiotic resistance and motility, and virulence factors production is regulated by a population density dependant phenomenon called quorum sensing(QS), a cell-to-cell communication ediated by autoinducer(AI) molecules. Destruction or inhibition of these AIs ceases the communication required for establishing the pathogenicity in plants called quorum quenching(QQ). Exploitation of QQ bacteria offers the most viable biocontrol strategy for the multidrug resistant phytopathogenic bacteria as these bacteria interfere with QS of phytopathogens only by degrading AIs and control virulence without hampering their growth. Preliminary screening of thirty-nine bacterial isolates obtained from eight different environmental samples by enrichment culture technique with C6HSL as QS molecule, using Chromobacterium violaceum MCC 4212 as a bioindicator yielded 14 isolates capable of inhibiting violacein production efficiently, a QS-mediated trait. Five of 14 isolates (HSL-13, HSL-31, HSL-32, HSL-61 and HSL-64) exhibited their QQ property without antagonism, a feature of an ideal QQ bacterium. In vitro maceration attenuation by five isolates in potato, radish and cucumber proved their biocontrol efficiency against soft rot pathogen, Pectobacterium carotovorum subsp. carotovorum(Pcc), a multidrug resistant bacterium. Attenuation of QS-mediated virulence factors of Pcc viz., plant cell wall degrading enzymes and biofilm formation by the bacterial isolates confirmed the QQ-based biocontrol efficiency of these QQ isolates with AHL degradation efficiency of >90% and are extracellular. In planta host range studies yielded three efficient isolates HSL-13, HSL-32 and HSL-64 that performed better in all five hosts. These quorum quenchers outperformed reference bacteria in their biocontrol as well as plant growth promoting potential in radish under pot culture conditions. Pseudomonas taiwanensis harbouring aiiA gene was identified in present study is responsible for AHL lactonase, quenches QS signals responsible for virulence by Pcc efficiently as predicted by molecular docking studies and rendered better biocontrol efficiency than others against the multidrug resistant Pcc.
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    SEARCH FOR ACTINOBACTERIA FOR PLANT GROWTH PROMOTION AND YIELD IN COWPEA (Vigna unguiculata L.) AND FINGER MILLET (Eleusine coracana L.)
    (University of Agricultural Sciences GKVK, Bangalore, 2022-12-17) NALINI, B.S; NALINI, B.S; Muthuraju, R; Muthuraju, R
    A study was conducted to isolate, screen of actinobacterial isolates for the growth promotional, biocontrol efficiency and evaluation of efficient isolates on growth and yield of cowpea and ragi under greenhouse conditions. Forty actinobacterial isolates were isolated. Biochemical characterization of actinobacterial isolates showed 2 isolates are positive for casein hydrolysis, 11 isolates for tyrosine, 20 isolates for H2S production, eight and seven isolates could produce melanin and iterate, respectively and negative for HCN and urease production. Among them, 26 isolates produced IAA and GA. UASBA46 and UASBA50 isolates showed he highest P, K and Zn solubilization with positive for siderophore, ammonia production. Highest concentration of ACC-deaminase activity and also production f hydrolytic enzymes observed in both the isolates. In vitro studies showed that 15 isolates were antagonistic against fungal pathogens Sclerotium Rolfson and Pythium spp 13 isolates were antagonists against Fusarium oxysporum. Further, actinobacterial isolates were identified as Streptomyces antibioticus UASBA50) and Streptomyces sp. (UASBA46) by 16s rRNA partial genome sequencing. Significant increase in plant growth and yield parameters was bserved in the treatment receiving dual inoculation of actinobacterial isolates with RDF in cowpea and finger millet. Significant increase in soil enzymes activity and total microbial population was also recorded. Jaggrey solution with NaCl+MgSO4+CaSO4 found to be the best substrate for mass multiplication of actinobacterial isolates. Hence the application of actinobacterial isolates has multiple growth and yield promotional activity as biofertilizers could serve as romising solution for improving soil health in sustainable crop production.