Identification and characterization of siderophore producing bacteria from Dalbergia sissoo Roxb. forest ecosystem
| dc.contributor.advisor | Sahgal, Manvika | |
| dc.contributor.author | Srivastava, Pragati | |
| dc.date.accessioned | 2021-01-29T05:36:20Z | |
| dc.date.available | 2021-01-29T05:36:20Z | |
| dc.date.issued | 2020-02 | |
| dc.description.abstract | Dalbergia sissoo Roxb. (family Fabaceae) is a large deciduous multipurpose timber tree. This high value cash tree is getting depleted due to dieback and wilt induced mortality. Hence, there is an urgent need to find ways for solving this problem. Soil microbes play a major role in plant health. Hence a comparative study of bacterial communities in the shisham forest (from rhisophere and bulk soil) at AFRC, GBPUAT, Pantnagar was done in cold dry (Oct- Dec) and monsoon wet (Jan-March) season through metagenomic approach. The variation in bacterial community in rhizosphere and bulk soil was not significant at both phylum and genus level. However there was variation within the seasons. Amongst ten most abundant bacterial phyla eight were common in both seasons. Common reported phyla were Acidobacteria, Actinobacteria, Bacteriodetes, Gemmatimonadales, Nitrospirae, Proteobacteria, Planctomyces, and Verrucomicrobia. Two genera Chloroflexi and Firmicutes were reported only in monsoon wet season and Cyanobacteria only in cold dry season. At genus level the variation was more pronounced. During monsoon wet season, the most abundant genera were unclassified iii1_15 within Acidobacteria, unclassified genus WD21010, Kaistobacter and Flavobacterium and genera WD2101;f ,Nitrospira, Kaistobacter, Pseudomonas, Candidatus Solibacter were abundant in cold dry season. The soil was alkaline and iron content was sufficient. The bioavailability of iron is low in alkaline soils. Thus, a total of twenty siderophore positive bacterial isolates were recovered from shisham forests in both the seasons. Of which, on the basis of qualitative and quantitative CAS assays, ten siderophore positive isolates were further identified and characterized. Through 16SrDNA sequencing and analysis, isolates were identified within genus Pseudomonas, Burkholderia and Streptomyces. Single factor optimization experiment revealed that siderophore production in all ten strains was between 100-70% siderophore unit (SU) and was significantly affected by pH, ammonium nitrate (NaNO3), and 50 μM FeCl3.6H2O. Siderophore production in five best siderophore positive strains Burkholderia territorii, Streptomyces lavendulae, Pseudomonas monteilli, P. chlororaphis and P. benzenovorans was optimized using response surface methodology. It was 70-90% SU with each strain having specific requirement for optimum siderophore production. FTIR and LCMS studies identified a derivative of ornibactin and pyochelin as siderophore in Burkholderia territorii strain whereas pseudomonine and salicyclic acid as siderophores in Pseudomonas monteilii strain. | en_US |
| dc.identifier.uri | https://krishikosh.egranth.ac.in/handle/1/5810160693 | |
| dc.keywords | identification, characterization, siderophores, bacteria, Dalbergia sissoo, forest management, ecosystems | en_US |
| dc.language.iso | English | en_US |
| dc.pages | 221 | en_US |
| dc.publisher | G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand) | en_US |
| dc.research.problem | Dalbergia sissoo | en_US |
| dc.sub | Microbiology | en_US |
| dc.theme | Bacteria | en_US |
| dc.these.type | Ph.D | en_US |
| dc.title | Identification and characterization of siderophore producing bacteria from Dalbergia sissoo Roxb. forest ecosystem | en_US |
| dc.type | Thesis | en_US |