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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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2012 - 201721
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Subject: Crop Physiology × End date: 2017 × Start date: 2012 × Thesis Type: Ph.D ×
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Now showing 1 - 9 of 21
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    ThesisItemOpen Access
    CHARACTERIZATION OF GROUNDNUT TRANSGENIC PLANTS CO-EXPRESSING THREE REGULATORY GENES TO IMPROVE DROUGHT RESISTANCE
    (UNIVERSITY OF AGRICULTURAL SCIENCES GKVK, BENGALURU, 2017-09-11) SWETHA, T.N.; Chandrashekara Reddy, P.
    Adaptation of groundnut crop under rain fed conditions can be achieved by improving suitable plant traits such as efficient water mining and cellular level tolerance (CLT) mechanisms. Pyramiding these drought adaptive traits by simultaneous expression of genes regulating root growth and sustaining cell metabolism by maintaining protein turnover has phenomenal relevance in improving stress. From this context, Groundnut transgenic plants expressing Alfin1, a root growth-associated transcription factor gene, heat-shock factor (PgHSF4) and PDH45 involved in protein turnover and protection have been developed. Emphasis in the present study is to identify superior promising events that possess higher root growth, tolerance and productivity. The transgenic plants showed more root growth at different developmental stages under both stress and non-stress conditions. Further, the transgenic plants exposed to diverse stresses like salinity, DTT and moisture stress, showed significantly superior performance compared to wild type. The productivity of transgenic lines was more compared to wild type under both stress and non-stress conditions. Based on stress tolerance with improved root growth and productivity eight promising lines were identified. Further, to decipher the molecular mechanism associated with improved root growth and tolerance the transcriptome, proteome and metabolome analysis was done in wild type and transgenic plant. From the transcriptome data it is evident that many root related genes and several heat shock genes were up regulated in transgenics under stress condition. In proteomics data, several root related and CLT associated proteins were up regulated. The metabolic profiling is integrated with proteomic and transcriptome data which provided basic leads in identifying key pathways contributing for improved adaptation, tolerance and productivity under stress condition. The data clearly demonstrates that over-expression of two or three regulatory genes improve drought adaptation by improving water relation and CLT mechanisms.
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    ThesisItemOpen Access
    CHARACTERIZATION OF RICE (Oryza sativa L.) TRANSGENIC PLANTS CO-EXPRESSING STRESS RESPONSIVE GENES HSF4, p68 AND Pg47
    (UNIVERSITY OF AGRICULTURAL SCIENCES GKVK, BENGALURU, 2017-03-27) SHEELA, H. S.; Chandrashekara Reddy, P.
    Rice grown under aerobic condition experience moisture stress due to decreased water availability and high Vapour pressure deficit ( VPD) which in turn affects the crop growth and productivity. From this context it is important to improve adaptation of rice under aerobic condition by improving water relations and cellular level tolerance mechanisms. For the crops grown under rain fed conditions (moisture stress), besides water mining, intrinsic cellular level tolerance (CLT) mechanismis important to sustain the cell metabolism. Even with higher water mining abilities under drought, plants experience decreased water status hence improving CLT mechanisms (osmotic adjustment, scavenging activity and protein synthesis and turnover) is important. Among CLT mechanisms, protein synthesis and turnover has greater significance. From this context, for improving translational process and protein stability under stress condition, transgenic approach was followed by co-expressing relevant stress responsive genes namely RNA helicases and HSF4. Since multiple traits control drought tolerance, an attempt has been made to co-express Pennisetum glaucum HSF4 (PgHSF4), Helicases like Pennisetum glaucum 47 (Pg47) and p68 (peanut p68) in rice. The results of present study revealed that, rice transgenics co-expressing PgHSF4, p68 and Pg47 genes were advanced from T3 to T5 generations and evaluated their performance under stressful environment. Several transgenic lines showed significantly improved stress tolerance in diverse physiological screens (Salinity stress, accelerated ageing stress, temperature stress and oxidative stress). In addition, transgenics also showed tolerance to semiirrigated aerobic conditions in the background of a genotype (AC39020) with superior water relations. Expression analysis of transgenes and other stress responsive downstream genes were higher in all selected transgenics compared to wild type. The best performing transgenic lines were selected and given for further evaluation to understand the molecular mechanism of tolerance.
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    ThesisItemOpen Access
    MOLECULAR CHARACTERISATION OF THE VARIABILITY IN CELLULAR LEVEL TOLERANCE IN RICE (Oryza sativa L.). AN ANALYSIS BASED ON METABOLOMICS APPROACH
    (UNIVERSITY OF AGRICULTURAL SCIENCES GKVK, BENGALURU, 2016-10-20) PUSHPA, D.; SHESHSHAYEE
    Aerobic cultivation can save up to 60 per cent of irrigation water in comparison with lowland rice, concomitant yield loss of upto 40 per cent is often noticed in aerobic cultivation, which is caused primarily due to an increased spikelet sterility. Better root systems coupled with higher cellular level tolerance (CLT) can significantly improve spikelet fertility under semi-irrigated aerobic condition. Cellular level tolerance (CLT) associated with production of compatible solutes and metabolites that reorganize proteins and cellular structures leading to maintenance of leaf turgor, cellular redox balance and homeostasis. Comprehensive profiling of solutes and metabolites in rice genotypes with varied level of drought tolerance and spikelet fertility would pave way in understanding the biochemical mechanisms at the cellular level and to identify genes responsible for high CLT under drought conditions. Fingerprint of biochemical perturbations could also be a reliable method to phenotype CLT under stress. Metabolite-based genome-wide association study (mGWAS) has emerged as a powerful alternative forward genetics strategy. In this study, differentially accumulated metabolites among drought tolerant and susceptible rice genotypes under well watered and water stress were measured using high resolution LC-MS. Metabolites that accumulated with significantly higher abundance in drought tolerant rice genotype compared to susceptible genotype upon stress induction were identified as Tolerance Related Induced (TRI) metabolites. Such TRI metabolites mainly belonged to primary metabolites: sugars, amino acids and secondary metabolites such as phenylproponoids, flavonoids and alkaloids. Primary metabolites mainly involved in synthesis of stress responsive proteins and osmoprotection and secondary metabolites as antioxidants, Reactive Oxygen Species (ROS) scavengers, coenzymes, UV and excess radiation screen and also as regulatory molecules. mGEWAS analysis identified genomic regions (QTL’s) associated with CLT and regulatory genes governing raffinose and GABA biosynthesis under drought stress in tolerant genotype.
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    ThesisItemOpen Access
    INTROGRESSION OF ROOT AND WATER USE EFFICIENCY TRAITS BY MARKER ASSISTED BACKCROSS (MABC) STRATEGY IN RICE (Oryza sativa L.) AND VALIDATION OF PROGENY THROUGH PHYSIOLOGICAL CHARACTERIZATION
    (UNIVERSITY OF AGRICULTURAL SCIENCES GKVK, BENGALURU, 2016-10-11) PRATHIBHA, M. D.; Sheshshayee, M. S.
    With the rapidly decreasing water resources, devising water saving agronomic practices rice cultivation is the most crucial need of the hour. Introgression of water mining and water use efficiency (WUE) traits on to a single elite genetic background is needed while developing aerobic worthy rice cultivars. In this investigation, a focused marker assisted backcross breeding approach was adopted to introgress the root and WUE traits into the elite genetic background of IR-64. In an earlier investigation, a panel of germplasm was characterized for molecular and phenotypic diversity leading to the discovery of trait donor genotypes (AC-39020 for roots and CLT, IET-16348 for WUE) and DNA markers for the traits by Association Mapping. Of the 50 markers associated with root and WUE traits, 16 markers found to be polymorphic and used as foreground markers. A set of 120 polymorphic genome wide SSR markers were used for background selection to reconstitute the recurrent parent genome. Three backcrosses were done and at DCBC3F1 generation four plants with maximum foreground and background were selected for further advancement by selfing. At DCBC3F2 generation a set of 1500 lines were screened under aerobic field conditions and the best lines (250) were advanced to DCBC3F3. These lines were extensively phenotyped for root, Δ13C and yield under aerobic conditions and identified 26 promising trait introgressed lines with background genome recovery of more than 95 percent and 30 per cent more yield than IR-64. These lines when grown under well-watered and water limited condition maintained higher growth and spikelet fertility compared to IR-64. This study significantly contributed for the development of trait introgressed lines that can be used for commercial cultivation and QTL-NILS that have great potential in academic understanding of QTL interactions.
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    ThesisItemOpen Access
    DEVELOPMENT OF MAPPING POPULATION AND IDENTIFICATION OF QTLS FOR HIGH ZINC CONTENT IN PIGEONPEA [Cajanus cajan (L.) Millsp.]
    (UNIVERSITY OF AGRICULTURAL SCIENCES GKVK, BENGALURU, 2016-04-23) BASAVARAJESHWARI, MATHAPATI R.; Shankar, A.G.
    Zinc plays key roles in plants and human health regulating several major physiological and biological processes. It has emerged as the most widespread micronutrient deficiency in soils and crops worldwide, resulting in severe yield losses and deterioration in nutritional quality, ultimately leading to human zinc deficiency. The short term interventions to curb human zinc deficiency are mineral supplementation, dietary diversification and food fortification but they are not economically viable in the long run. So, biofortification through genetic or agronomic approaches may be a long lasting solution to cater the needs of both the rural and urban population. In this direction, 30 high and low zinc genotypes selected out of 217 germplasm lines outsourced from ICRISAT were genotyped to analyze their genetic diversity using 50 SSR markers. Cross were conducted between selected lines. Of the crosses, the cross ICP6443 X ICP10960 was used to develop mapping population segregating for seed Zn content and subsequently used for phenotyping, linkage mapping and QTL analysis. Significant phenotypic variability was noticed for the seed zinc and other traits in the population. The polymorphic information of 151 SSR markers were used to construct linkage map. Multipoint linkage analysis resulted in linkage map of 62 markers into 10 linkage groups with a total map length of 1942.8 cM. QTLs for seed zinc, leaf zinc and yield traits were identified using linkage mapping. Several pleiotropic markers were identified for different traits in QTL analysis. Single marker analysis and composite interval mapping resulted in discovery of common markers (AHSSR93, AHSSR118 and ASSR280) for seed zinc content. The study lead to discovery of several transgressive segregates with high seed zinc content, serving as potential genetic resources. An important genic marker bZIP transcription factor (ASSR20) speculated to regulate zinc deficiency response is found to be linked to seed zinc content.
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    ThesisItemOpen Access
    Transcriptional regulation to enhance drought tolerance in plants: Co-expression of AhBTF3, AhNF-YA7 and EcSAP-ZF in rice and characterization of novel regulator, EcTAF6 in model system
    (UNIVERSITY OF AGRICULTURAL SCIENCES GKVK, BENGALURU, 2015-12-12) PARVATHI, M. SREEKUMAR; Nataraja, Karaba
    Drought adversely affects crop productivity in tropical countries. To improve crop drought tolerance, modern approaches like molecular breeding and/or transgenesis are used to pyramid traits. In this study, an attempt was made to manipulate transcriptional regulation by co-expressing three stress responsive transcriptional regulators (TRs), AhBTF3, AhNF-YA7 and EcSAP-ZF to enhance cellular tolerance under drought in rice. The putative transgenic plants tolerant to glyphosate were confirmed for transgene integration and expression. The T2 plants exhibited better growth performance under nonstress conditions compared to wild type. The superior stress response of transgenic lines was evidenced in excised leaf disc and seedling level assays under multiple abiotic stresses. The selected lines had better pollen viability and grain yield than wild type, post drought at reproductive stage. Superior T3 lines displayed enhanced tolerance to transcription and translation inhibition, and organellar stresses. Six promising lines have been forwarded to T4 generation for productivity analysis. Additionally, efforts were made to prospect novel TRs from dry-land crop, finger millet, by analysing a drought stressed leaf transcriptome data. This led to the identification and cloning of EcTAF6, a subunit of transcription pre-initiation complex. Expression analysis of TAF6 in finger millet and Brassica rapa revealed responsiveness to multiple stresses. Two splice variants of EcTAF6, probably resulting from alternative splicing, were discovered in stressed leaf cDNA. The functional characterisation of TAF6 by down regulation using Virus Induced Gene Silencing approach in Nicotiana benthamiana, and Arabidopsis attaf6 mutants demonstrated its relevance under stress. Transgenic Arabidopsis have been developed to over-express EcTAF6 which are to be evaluated further. This study, for the first time, indicated that TAF6 could be a key regulator in multiple stress response networks. In conclusion, the study has demonstrated that basal transcriptional regulators can be the novel candidates for enhancing cellular tolerance of crops under drought conditions.
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    ThesisItemOpen Access
    STACKING OF UPSTREAM REGULATORY GENES TO CONFER ABIOTIC STRESS TOLERANCE IN RICE (Oryza sativa L.)
    (UNIVERSITY OF AGRICULTURAL SCIENCES GKVK, BENGALURU, 2015-12-03) PATIL, MAHESH; Chandrashekara Reddy, P
    Rice cultivation under aerobic condition has phenomenal relevance in terms of saving water. But reduced water availability and high VPD affecting crop growth and productivity. Thus it is important to improve adaptation of rice under aerobic condition by improving water relations and cellular level tolerance (CLT) mechanisms. Improving CLT to sustain cell metabolic activities has relevance under stress and among several CLT mechanisms, protein synthesis and stability are crucial. From this context, an attempt has been made to validate three regulatory genes i.e. Pg47 (Pennisetum glaucum 47, a RNA helicase), OseIF4E (Oryza sativa translational initiation factor 4E) and PgHSF4 (Pennisetum glaucum heat shock factor 4) involved in protein synthesis and protection in a model system tobacco. Transgenics expressing single and multigene cassette showed higher tolerance to diverse stresses viz. salinity, ER, heavy metal, drought and osmotic stress, besides showing enhanced expression of few stress responsive genes compared to wild type under stress. However, lines expressing multigene cassette showed superior phenotype and tolerance over lines expressing single genes with significantly higher protein content and lesser malondialdehyde level. This demonstrated the significance of co-expressing more than one stress specific genes/TFs over single gene. To improve adaptation of rice under semi-irrigated aerobic conditions rice transgenics co-expressing multigene cassette were developed in the background of AC39020 genotype having superior water relations. True transformants were identified based on glyphosate tolerance. The transgenics showed improved tolerance to salinity, ER and heavy metal stress apart from drought stress. Under drought stress, many promising transgenic lines showed reduced spikelet sterility and higher yield compared to wild type. The study provides proof of concept that maintaining efficient translation and protein protection improves CLT and transgenic is a potential option to combine or pyramid the relevant traits to improve field level tolerance.
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    ThesisItemOpen Access
    GENETIC MODIFICATION OF TOMATO (Solanum lycopersicum) TO INCREASE THE UPTAKE AND TRANSLOCATION OF ZINC
    (UNIVERSITY OF AGRICULTURAL SCIENCES GKVK, BENGALURU, 2015-09-09) PAVITHRA, G. J; Shankar, G
    Zinc (Zn) is one of the essential micronutrient with major biological roles both in plants and humans. Deficiency of Zn is by far the most ubiquitous problem in the world affecting the plant and human nutrition. Zn deficiency in humans can be addressed through dietary diversification, mineral supplementation, food fortification and biofortification. Among these, biofortification of food crops either through genetic engineering or molecular breeding approaches is considered to be promising and sustainable. To achieve this better understanding of molecular mechanisms regulating the Zn uptake and transport in plant is most crucial. In the present investigation an attempt was made to identify the candidate Zn transporter gene in tomato responsible for high fruit Zn content. Initially 41 tomato genotypes were screened for Zn content. The contrast lines identified based on the fruit Zn content were subjected for Zn deficient and sufficient conditions and analysed for Zn transporter expression through RT- PCR. The candidate Zn transporter genes up-regulated in the high Zn type germplasm lines, SlZIPL and SlZIP4 were identified and cloned. Further the genes were sub-cloned to pBINPLUS binary vector driven by constitutive promoter (CaMV35S) and the two independent gene constructs PCaMV35S: SlZIPL: TpolyA and PCaMV35S: SlZIP4: TpolyA were used for plant transformation. To develop transgenic tobacco and tomato plants, Agrobacterium mediated tissue culture technique was followed. Few tobacco transgenic lines over expressing SlZIPL and SlZIP4 showed high leaf Zn and chlorophyll content. Similarly, tomato SlZIPL and SlZIP4 transgenics also showed high fruit, leaf and petiole Zn content compared to wild type. Further the RT-PCR expression analysis of tomato transgenics showed the higher expression of SlZIPL and SlZIP4. These results imply that, SlZIPL and SlZIP4 are candidate Zn transporters in tomato involved in better Zn transport and hence high fruit Zn content
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    ThesisItemOpen Access
    ENHANCING OXIDATIVE STRESS TOLERANCE IN AEROBIC RICE (Oryza sativa L.); VALIDATION OF ROS SCAVENGING ENZYMES BY TRANSGENIC APPROACH AND IDENTIFICATION OF OXIDATIVE STRESS SPECIFIC UPSTREAM GENES
    (UNIVERSITY OF AGRICULTURAL SCIENCES GKVK, BENGALURU, 2015-09-28) JALENDRA KUMAR, H. G; Udayakumar, M
    Rice crop grown under aerobic conditions experience moisture stress between irrigations resulting in oxidative stress, which is a major constraint to realize potential yields. One of the most common strategy to improve tolerance to oxidative stress is by overexpressing either single or multiple antioxidant genes by transgenic approach. The second strategy is to overexpress the upstream regulatory genes, mainly transcription factors (TFs) specific to oxidative stress. A novel T7 polymerase based multigene construct consisting of 5 antioxidant genes of the Asada Halliwell pathway viz., SOD, APX, DHAR, MDHAR and GR was developed and transformed into two selected aerobic rice genotypes-AC39020 and KMP175 by in planta transformation technique. Promising lines were identified based on stable integration of transgenes and response to oxidative stress. In T4 generation 13 lines of each genotype were assessed for tolerance to oxidative stress, moisture stress and high temperature stress along with grain yield under moisture stress conditions. The other objective of the study was to identify TFs associated with oxidative stress. The transcriptomic profile was assessed by microarray analysis in two contrasting rice genotypes (AC39020-tolerant & BPT5204-susceptible) subjected to oxidative stress. Among the 918 differentially expressed genes, 38 were TFs and 2 were kinases. About 20 TFs were shortlisted by extensive in silico analysis which included spatial expression profile, presence of ROS- elements, meta-analysis and coexpression matrix. To accurately characterize the stress response of transgenics and germplasm accessions a novel minilysimeter based phenomics facility was developed. The facility could monitor and maintain a desired soil moisture status and precisely control dry down rates. The facility successfully brought out the differences in growth between the contrasting rice genotypes by maintaining both at 70 per cent FC±5 per cent Based on the results of the pilot project, a new high through put phenomics facility was developed with 450 minilysimeters.