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ThesisItem Open Access Growth promotory effect of drought tolerant bacteria on wheat crop under drought stress(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2017-07) Gouri, Vinita; Singh, Ajay VeerIn natural environmental condition plants continuously exposed to various biotic and abiotic factors. Drought is considered as major abiotic stress and adversely affects plant growth and productivity worldwide. Plants under drought stress conditions show reduced root length, shoot length, deficiency of nutrients and increases disease susceptibility and hence decreases economic yield of crop. In this context, present study was carried out with the application of drought tolerant plant growth promoting rhizobacteria (PGPR) in wheat to promote growth and productivity under drought stress conditions. During study, total sixty bacterial isolates were retrieved and revived from departmental culture collection. On the basis of growth present on tryptic soy broth medium supplemented with 6% poly ethylene glycol and 20% NaCl, fourteen bacterial isolates were selected as drought tolerant. These drought tolerant bacterial isolates were further checked for plant growth promoting activities such as siderophore production, zinc solubilization, phosphate solubilization and ACC deaminase activity and ten best potential bacterial isolates were screened for further study. Afterward, screened potential bacterial isolates were selected and characterized on the basis of cell and colony morphology, biochemical characteristics and carbohydrate utilization tests. Now these potential isolates were characterized functionally and tested for plant growth promoting traits such as exopolysaccaride production, ammonia production, indole acetic acid production and hydrogen cyanide production. Furthermore, potential bacterial isolates were evaluated for antibiosis activity against two pathogenic fungi of wheat, four isolates were able to suppress mycelial growth of Fusarium oxysporum and three bacterial isolates were able to suppress mycelial growth of Alternaria spp. However, SRPII7 isolate was effective against both the fungi. Furthermore, an in situ greenhouse pot experiment was designed under drought stress with all ten drought tolerant plant growth promoting isolates with early variety of wheat (Triticum aestivum var. UP-2785). Results of green house pot experiment confirmed that all bacterial isolates were significantly able to improve plant growth and productivity in terms of agronomical parameters such as root length, shoot length, dry weight of plant, spike length, number of grains/spike, 1000 grains weight and % harvest index, while four bacterial isolates i.e. WRPA13, WRPA26, SRA1 and SRK14 prove more potential compare to all other isolates and helps wheat plant to cope up with drought stresses. In vitro and in situ studies depicted the potentiality of four bacterial isolates for their promising plant growth promoting activity under drought stress. In respect to said results, present study concluded that these four potential bacterial isolates i.e. WRPA13, WRPA26, SRA1 and SRK14 can be employed as bioinoculant/biofertilizer to improve drought tolerance and nutrient enhancement in wheat crop for sustainable agriculture.ThesisItem Open Access Nodulation and nitrogen fixation of Cicer arietinum L. under drought(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2014-06) Karmakar, Kapudeep; Sahgal, ManvikaMembers of genus Mesorhizobium were the natural symbiont of Cicer arietinum L. In contradiction to above, however, Ensifer meliloti (formally known as Sinorhizobium meliloti) have been recovered from the nodules of Cicer arietinum L. growing in Almora and Pantnagar as well as arid regions of Tunisia. Six rhizobial strains, four belonging to genus Mesorhizobium and two to Ensifer were screened for their tolerance to salt, drought and six antibiotics. Their ARDRA profiles were also studied. Based on these characteristics, two strains, one belonging to Mesorhizobium i.e. Mesorhizobium temperatum and other Ensifer i.e. Ensifer meliloti MTCC 11403 were selected for further investigation. To investigate the factors governing elicitation of effective nodules on Cicer arietinum either by Mesorhizobium temperatum or Ensifer meliloti MTCC 11403, a polyhouse trial was carried out on C. arietinum L. variety PG-162 with inoculation of Ensifer meliloti MTCC 11403 and Mesorhizobium temperatum individually and in coculture under drought and normal watering regime and nodulation, nodule occupancy and nitrogen fixation ability was assessed. Of the two, Ensifer meliloti MTCC 11403 occupies the nodules and fixes nitrogen only under drought whereas Mesorhizobium temperatum under normal watering. However in co-inoculated plants both the strains occupy the nodules. And fix nitrogen under stress as well as normal watering. In an in-vitro trial to assess the major colonizer of the rhizosphere, Ensifer meliloti MTCC 11403 was dominant under drought (both in pure culture and in co-culture) over Mesorhizobium temperatum. Further, both these strains were checked for their EPS production and proline accumulation at varying levels of water potentials. Of the two strains, Ensifer meliloti MTCC 11403 produced higher EPS (265.54±7.09 µg ml-1) as compared to Mesorhizobium temperatum (124±3.72 µg ml-1) after 72 hours at 1.5 MPa water potential. However, the production of proline was comparable. The soil of Pantnagar was analysed and was found to have an EC value of 2.2 dS mho-1 which shows the accumulation of salts over a long period of cultivation. This explains the reason for nodulation of C. arietinum L. by Ensifer meliloti MTCC 11403 in Pantnagar. Moreover, Ensifer-Cicer symbiosis is efficient than Mesorhizobium-Cicer symbiosis under drought.ThesisItem Open Access Mycoremediation of toxic synthetic industrial dyes using lignolytic fungal isolates(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2016-07) Rana, Babita; Tewari, LakshmiThesisItem Open Access Assessment of Pseudomonas fluorescens AS15 inoculation on growth and establishment of Dalbergia sissoo nursery(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2016-06) Dasila, Hemant; Sahgal, ManvikaThesisItem Open Access Zinc and iron biofortification strategies through plant growth promoting Rhizobacteria in wheat(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2016-08) Rawat, Saloni; Singh, Ajay VeerThesisItem Open Access Phosphate solubilization by indigenous soil microbiodata under stress conditions(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2016-08) Bisht, Seema; Tewari, LakshmiThesisItem Open Access Behaviour of TiO2 nanoparticles on plant growth promotory Rhizobacteria and soil properties of maize rhizosphere(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2016-06) Hema Kumari; Sharma, AnitaThesisItem Open Access Comparative phylogenetic analysis of chickpea nodulating rhizobia from Central India and Terai region of Western Himalayas(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2017-07) Maithani, Damini; Sahgal, ManvikaThesisItem Open Access Effect of two nanocompounds on fenugreek vigour and soil health under the influence of plant growth promoting rhizobacteria(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2017-06) Swati Kumari; Sharma, AnitaNanotechnology has been designated as one of the most potential field for research that permits researchers to control the materials at molecular, macromolecular and atomic level. The characteristics of nanomaterials and their utility differ notably from the original compound at macroscopic scale. Effect of two nanocompounds (Nanozeolite and Nanochitosan) on germination and vigour of fenugreek and soil health under the influence of Plant Growth Promoting Rhizobacteria was studied in a pot experiment. Two bacterial isolates (PS2 and PS10) were selected on the basis of their plant growth promoting properties. PS2 and PS10 were characterized on the basis of molecular characters and found to have homology with Bacillus sp. on the basis of BLAST and were allotted with accession number as KX650178 and KX650179, respectively. PS2 and PS10 produced 44.96 and 23.16 % Siderophore unit, 13.84 µg/ml and 9.29 µg/ml IAA and solubilized 2.34 µg/ml P and 2.22 µg/ml P, respectively. Enhanced average plant height, no. of leaves, leaf area and fresh weight (1.5 - 2.0 folds) over control was observed in the presence of nanocompounds + bacterial treatments. Average total chlorophyll (3.27 mg/g) and catalase activity (23.84 U/g tissue) was maximum for PS2+Nz treatment. Total soluble leaf protein was maximum (295.37mg/g fresh weight) in the PS2+Nch treatment, which was 10% more than control. Total sugar was maximum (6.14 µg/mg dry wt.) in PS10+Nz treatment and was about 13% more than control. After 45 days of pot experiment, maximum fluorescein diacetate hydrolysis activity (2.5 fold increase) was observed in the soil under treatment of PS10+Nz. Maximum alkaline phosphatase activity i.e., 41.35 µg/g/h (11% increase) was reported in the PS10+Nz treatment whereas maximum dehydrogenase activity i.e., 3.65 µg/5g/8h (2.2 fold increase) was observed in the PS10 treatment. It can be concluded from our findings that application of nanocompounds along with bacterial treatments improved plant-bacterial interaction, promoted plant parameters, increased microbial diversity and increased the level of soil health indicator enzymes.