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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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Subject: Crop Physiology × End date: 2013 × Start date: 2013 × Type: Thesis × Thesis Type: Ph.D ×
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Now showing 1 - 7 of 7
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    ThesisItemOpen Access
    Validation of abiotic stress responsive transcription factors by over expression in crop plants
    (University of Agricultural Sciences GKVK, Bangalore, 2013-03-19) Pruthvi, V.; NATARAJA KARABA, N.
    Drought, temperature extremes and salinity are the most common abiotic stresses, adversely affecting plant growth and productivity. Plants activate stress signalling pathways, biochemical and physiological processes necessary for stress adaptation upon stress induction. Although stress tolerance is governed by multiple traits, a few traits play a major role in adaptation. Under drought, traits linked to water mining and water conservation, water use efficiency and cellular tolerance (CT) to desiccation are considered to be relevant. In this study, attempts have been made to improve CT in drought hardy crop, peanut (Arachis hypogaea, cv. TMV2) and susceptible crop, sunflower (Helianthus annuus, IB20) by coexpressing stress-responsive transcription factors (TFs, namely, AtDREB2A, AtHB7 and AtABF3), the major proteins associated with gene expression. Transgenic crops showed increased tolerance to drought, salinity and oxidative stresses compared to wild type. Simultaneous expression of three TFs induced the expression of various stress responsive genes including detoxifying enzymes, protein kinase, RD29a, LEA and chaperons indicating that co-expression of TFs can be a good strategy to improve stress tolerance by activating multiple pathways. Attempts have also been made to prospect candidate TFs from drought hardy crop, peanut, and three different TFs, namely, AhZinc finger, AhBTF3 and AhNFYA7 were cloned from cDNA and functionally validated under different stresses by over expression in model plant, tobacco. AhZinc finger overexpression resulted in an increased expression of detoxifying enzymes leading to enhanced tolerance to heavy metal stress. AhBTF3 transgenic plants showed better phenotype under mannitol- and NaCl-induced stresses. Similarly, AhNFYA7 transgenic plants exhibited increased tolerance under DTT- and tunicamycin-induced ER stresses. The study demonstrated that the three genes cloned have relevance in improving cellular tolerance under stressful conditions.
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    ThesisItemOpen Access
    Assessment of variability for phytic acid content in mini-core germplasm lines of finger millet (Eleusine coracana (L.) Gaertn.) and development of RNAi Lines for low phytic acid content
    (University of Agricultural Sciences, Bengaluru, 2013-12-13) B. H, Rajashekar Reddy; A. G, Shankar
    Phytic acid is generally regarded as the primary storage form of phosphorous, from human nutrition perspective, Phytic acid is an efficient chelator of nutritionally important mineral cations such as Ca, Fe, Mg, Zn etc. ,and these nutrients are not bioavailable for monogastric animals including humans. For these reasons, in the last two decades one of the biofortification approaches has been the isolation and development of ‘low phytate’ (lpa) cereals and legume genotypes with the aim to improve bioavailability of already existing nutrients in food crops. Finger millet is considered as one of the important minor cereal due to high nutritional value with highest calcium content among staples foods. Initially in our study to access the variability for phytic acid content 124 finger millet germplasm lines were screened for phytic acid and inorganic phosphorous content. Analysis of Variance for mean values revealed the significant differences among the accessions for phytic acid and Inorganic phosphorous. Further estimation of genetic parameters showed variations for the trait were mostly due to genetic factors and Principal Component Analysis also revealed Phytic acid is component contributing to the variability across germplasm accessions. The rate limiting enzyme in phytic acid biosynthesis is myo-inositol 3-phosphate synthase (MIPS) and altering MIPS expression in developing seeds may lead to a valuable reduction in phytic acid content. In this direction, full length MIPS gene (1818 bp) from immature embryo of finger millet was cloned. In-silico analysis of EcMIPS gene sequence showed longest coding region of 1533 bp which encodes 510 amino acid residues with NAD Binding 5 super family domain which is characteristic feature of MIPS enzymes. Further, RNA interference (RNAi) technology was used for down regulation of MIPS. An efficient siRNA forming region from EcMIPS without any off- targets were identified and these regions were used to develop RNAi constructs both under constitutive and endosperm specific promoter. For plant transformation Agrobacterium mediated gene transfer technology was followed. Characterization of putative transformants with reduced phytic acid content need to be performed.
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    ThesisItemOpen Access
    Targeting genes for ion homeostasis and salt tolerance in finger millet (Eluesine coracana (L) Gaertn. ): Over-expressing genes for salt compartmentation and proton gradient generation and their significance in salt tolerance
    (University of Agricultural Sciences, Bengaluru, 2013-12-12) K. M, Vasantha; V. R, Shashidhar
    Salinity in agricultural terms is the excess of salts above the level plant requirement. Most often it poses constraints in the growth hence productivity of the crop plants gets affected and therefore is a serious concern. Salinity is one of the major abiotic stresses affecting plant productivity. Finger millet (Eluesine coracana (L.)Gaertn), is grown on over 4 million hectare worldwide and it is a primary food for millions in dry lands and is sensitive to moderate levels of salt in the soil. To generate finger millet plants that can adapt to saline soil, AVP1, a vacuolar H+-pyrophosphatase gene from Arabidopsis thaliana, and PgNHX1, a vacuolar Na+/H+antiporter gene from Pennisetum glaucum, were co-expressed by Agrobacterium tumefaciens-mediated transformation and attempts has been made on standardization of an efficient direct regeneration protocol in finger millet. The shoot meristem was found to be the best responsive explants for direct organogenesis. The functional significance of AVP1, NHX1 and AVP1::NHX1 transgenic plants was demonstrated invitro and invivo by using Hydroponics’ systems, gravimetric analysis and soil system by Karnal method. Physiological studies such as CMS, Nutrient estimation of Na, K, and Ca, chlorophyll stability index, Standard Evaluation Score for visual salt injury, Proline, OA and yield analysis. It is reported here that co-expression of AVP1 and PgNHX1 confers enhanced salt tolerance to the transformed finger millet compared with the AVP1 and PgNHX1 single gene transgenic plants and the wild-type. These transgenic plants grew well in the presence of 20 dS/m NaCl while wild-type plants exhibited chlorosis and died within the 30days.The physiological analysis of the transgenic lines clearly demonstrates that co-expression of AVP1 and PgNHX1 improved the osmoregulatory capacity of double transgenic lines by enhanced sequestration of ions into the vacuole from cytosolby increasing the availability of protons and thus alleviating the toxic effect of Na+
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    ThesisItemOpen Access
    Role of cytokinin in growth and development of groundnut: A transgenic approach
    (University of Agricultural Sciences, Bengaluru, 2013-11-02) Babli, Mog; T. G, Prasad
    Transgenic lines with bacterial ipt gene to increase endogenous cytokinin concentration in groundnut variety TMV-2 was developed and promising putative transgenic lines were selected. In the present investigation, 54 putative transgenic lines in T3 generation were analyzed for further physiological and yield characters. Based on leaf chlorophyll content and pod yield, 49 lines were advanced to T5 generation. Transgenic lines on an average had 27 and 32 percent more chlorophyll at the end of NaCl and Ethrel stress and also higher NRA activity. Based on chlorophyll content, NRA, pod yield and biomass, 22 lines were promoted to T6 generation. Transgenic lines maintained relatively higher leaf chlorophyll content and membrane integrity in response to NaCl and Ethrel stress. Transgenic lines also showed higher NRA activity, bigger leaves, more biomass production, pod number and pod weight at harvest. Based on pod yield per plant, 11 lines were advanced to T7 generation. Transgenic lines maintained more green leaf area, higher pod number and pod weight in two pot culture experiments conducted. Based on PCR, RT-PCR and southern blot analysis, three ipt transgenic lines were selected from previous generations to study influence of NaCl and moisture stress on physiological and growth parameters under both stress and non-stress conditions. Transgenic lines showed higher leaf chlorophyll content, nitrate reductase activity, less membrane leakage and higher total leaf area both under non-stress, at the end of NaCl stress and during recovery from NaCl stress. All the transgenic lines maintained higher leaf area and biomass in shoot and root under both non stress and stress conditions. An attempt was also made to develop transgenic groundnut lines maintaining high endogenous cytokinin concentration by reducing the concentration of cytokinin degrading enzyme-CKO by antisense approach. Groundnut transgenic plants overexpressing pFGC5941: CKO gene was developed by Agrobacterium mediated inplanta transformation. Putative transgenic lines were screened over different concentrations of basta and CKO gene was confirmed by gene specific and bar primers in transgenic lines. The putative transgenic lines showed significant increase in pod number, pod yield, total shoot biomass accumulation and root weight per plant.
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    ThesisItemOpen Access
    Discovery of QTL for root traits and water use efficiency in rice (Oryza sativa L.) and their validation - A combined approach of association analysis and linkage mapping
    (University of Agricultural Sciences, Bengaluru, 2013-08-24) B. R, Raju; M. S, Sheshshayee
    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. Considering the complexity of inheritance of these traits, a focused molecular breeding is a promising approach. A set of 173 diverse indica rice accessions were phenotyped for these traits and significant variability was noticed which was consistent across seasons, indicating a strong genetic control. Assessment of molecular diversity using 291 SSR markers detected a total of 2,615 alleles with an average of 8.95 allele per locus and an average PIC value of 0.6. Population structure analysis identified six main subgroups which corresponded to the diversity analysis derived from neighbour joining method. Of the 108 significant marker-trait associations (MTAs) identified using mixed linear model, 51 were highly significant (P<0.01). There were 24 associations for Root traits and 1 for 13C and 16 for other physiological traits. Many of these markers were found to be located in QTL regions previously reported for similar traits. A trait specific mapping population was characterized for root traits and WUE under aerobic conditions validating the associated markers. Significant phenotypic variations with transgressive segregants were found for all the traits and 30 QTLs were detected. The combined approach of association and linkage mapping lead to the identification of several common markers viz., RM1235, RM8020, RM4477, RM163 and RM307 linked with the traits of interest. These markers can significantly enhance breeding efficiency in introgressing complex traits. This novel two pronged strategy lead to the discovery of 13 robust QTLs which on in-silico analysis revealed the presence of genes that govern variability in cellular metabolism, transport and signal transduction, transcription and hormonal regulation under abiotic stress adaptation and yield improvement in rice.
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    ThesisItemOpen Access
    Adaptation of Rice (Oryza sativa L.) root-morphology and anatomical characteristics in flood-saturated and aerobic condition
    (University of Agricultural Sciences, Bengaluru, 2013-07-25) Kabeya, Muamba Jerry; A. G, Shankar
    Yield penalty and yield stability of aerobic rice have to be considered in order to promote water-saving technology in sub-tropics and tropics. The objective of this study were (1) evaluation of field performance for yield, yield components and physiological attributes of lowland and aerobic rice genotypes under flood-saturated and aerobic condition (2) assess genetic variation of root of root morpho-anatomical characteristics of the lowland and aerobic rice under flood-saturated and aerobic condition (3) assess availability of soil indigenous zinc and iron and uptake ability in lowland and aerobic rice genotypes under flood-saturated and aerobic condition. Field experiments were conducted in native and contrast environment for each germplasm ecotype in two seasons. The yield difference between aerobic condition (average yield, 6.56 g/plant) and flood-saturated condition (average yield, 9.37 g/plant) for aerobic rice genotypes ranged from 20.4 to 35.8% depending on varieties but among lowland rice genotypes, the yield difference between aerobic condition (average yield, 13.44 g/plant) and flood-saturated condition (average yield, 17.22 g/plant) ranged from 18.5 to 33.2% depending on varieties. Among the yield components assessed, sink size (spikelets per panicle) and number of effective tillers contributed more to the yield and is considered to be most important factor responsible for yield gap between aerobic and lowland rice genotypes. To clarify the differences in root anatomical and morphological traits among aerobic and lowland genotypes grown in native and contrast environments, we analyzed few anatomical and morphological traits. The root samples were prepared from 20 mm of tip. Root cross-sections were stained with saffranine and fast green stains. Anatomical differences were observed among all genotypes submitted to water management and varied between the water managements. The number and diameter of metaxylem vessels were grown under aerobic condition tended to have greater number and smaller size of metaxylem vessels relative to stele size in comparison with the genotypes grown under flood-saturated condition. A decrease in root’s aerenchyma was observed in all genotypes in aerobic condition compared to the flood-saturated condition. High genetic variability was observed in all morphological characteristics in all genotypes, and highly influenced by water managements. Field experiments demonstrated that the cultivation (flood-saturated and aerobic condition) greatly affected the uptake of indigenous zinc and iron, and also the availability in different plant parts including grains, among the genotypes studied. Lower uptake in zinc or iron and as well availability were observed in aerobic fields compared to flood-saturated fields. This large variation in uptake and availability is a pre-requisite for initiating a breeding program to develop mineral-rich genotypes adaptive to an environment-specific.
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    ThesisItemOpen Access
    Engineering drought tolerant traits in rice
    (University of Agricultural Sciences, Bengaluru, 2013-06-29) B. H, Nagaveni; N, Nataraja karaba
    Plants being sessile are persistently exposed to various abiotic stresses, which are inevitable and less predictable. So, it is crucial to understand the mechanism that may help the plant to tolerate the stress conditions. Abiotic stress tolerance is multigenic character and stress responsive genes involved in this complex mechanism are many, among which transcription factors (TFs) are the major regulators of gene expression in plants. TFs, which play a crucial role in stress tolerance of plants, assume great importance in the development of tolerant crop varieties. Since the threshold for tolerance differs amongst the species, identification and functional characterization of genes/TFs from stress adapted crop species assumes importance. The present study involves improving drought tolerance by overexpressing TFs associated with intrinsic cellular tolerance and water conservation in a rice genotype AC39020 having a few drought tolerant traits. The candidate genes were cloned from drought hardy grass species Cenchrus ciliaris and tolerant rice landrace, Dodiga. The NFY-B1 was cloned from C. ciliaris, while the SKIP1 and SHN1 were cloned from Dodiga using PCR based cloning approach. Transformation protocol for the genotype AC39020 was developed and the three transgenes were overexpressed in isolation and co-expressed simultaneously in single plant. Evaluation of transgenic plants at seedling stage under different abiotic stresses using physiological, biochemical and growth parameters indicated the relevance of theses genes. The transgenic plants showed improved drought tolerance and grain yield by reduced spikelet sterility. Co-expression of three TFs is relevant in improving cellular tolerance in rice.