Prospecting plant growth promoting and endophytic bacteria for improving growth and yield of sunflower (Helianthus annuus L.)

Simple item page
dc.contributor.advisorVyas, Pratibha
dc.contributor.authorKiranjot Kaur
dc.date.accessioned2023-12-11T13:07:50Z
dc.date.available2023-12-11T13:07:50Z
dc.date.issued2023
dc.description.abstractThe current study was carried out with the aim to develop a plant growth-promoting bacterial inoculant for improving the growth and yield of sunflower. A total of 64 morphologically distinct bacteria were isolated from leaves, stem, roots and rhizosphere of sunflower collected from the fields of Punjab Agricultural University, Ludhiana. The isolates were screened for multifarious plant growth-promoting traits viz. solubilization of phosphate and zinc; production of auxins, siderophore, ammonia, hydrogen cyanide, and growth on nitrogen free medium. Thirty-three bacterial isolates showed solubilization of phosphate with solubilization index ranging from 2.7 to 3.8 by rhizospheric bacteria and 2.4 to 5.4 by endophytic bacteria on modified Pikovaskaya agar. In liquid medium, phosphate solubilization ranged from 3.6 to 171.6 μg/ml by the rhizospheric bacteria and 1.1 to 889.5 μg/ml by endophytic bacteria. Thirty isolates showed zinc solubilization, 25 isolates showed siderophore production while 40 isolates showed luxuriant growth on different nitrogen free media. All the isolates were positive for auxin and ammonia production but negative for hydrogen cyanide production. Based on multiple plant growth-promoting traits, nine potential bacterial strains were tested for growth promotion of sunflower in pots. The isolates showed a significant increase in growth, chlorophyll content and N, P and K contents of plant and soil samples with the bacterial inoculations over the uninoculated control. Three isolates showing the highest growth promoting activity were identified by phenotypic features, biochemical tests and MALDI-TOF-MS analysis as Pseudomonas aeruginosa SRB1, Advenella kashmirensis SLE1 and Brevendimonas dimunata SLE15. The field evaluation of three potential bacterial strains Pseudomonas aeruginosa SRB1, Advenella kashmirensis SLE1 and Brevendimonas dimunata SLE15 and their consortium was carried out with and without 75 and 100 per cent recommended dose of fertilizers for sunflower. The highest growth promotion, nutrient content and yield enhancement was recorded with the treatment AkSLE1 + BdSLE15 + PaSRB1 with 100 per cent RDF which was statistically not different from that obtained with the treatment AkSLE1 + BdSLE15 + PaSRB1 with 75 per cent RDF, indicating the potential of these three PGPB strains in saving around 25 per cent N, P and K fertilizers for sunflower. The study has led to the selection of a plant growth-promoting bacterial consortium as a potential bacterial inoculant for improving the growth, yield and nutrient content in sunflower.
dc.identifier.citationKiranjot Kaur (2023). Prospecting plant growth promoting and endophytic bacteria for improving growth and yield of sunflower (Helianthus annuus L.) (Unpublished M.Sc. thesis). Punjab Agricultural University, Ludhiana, Punjab, India.
dc.identifier.urihttps://krishikosh.egranth.ac.in/handle/1/5810202605
dc.keywordsGrowth promotion
dc.keywordssunflower
dc.keywordsmultifarious
dc.keywordsphosphate solubilization
dc.keywordsauxins
dc.keywordshydrogen cyanide
dc.keywordssiderophore production
dc.keywordsconsortium
dc.language.isoEnglish
dc.pages77
dc.publisherPunjab Agricultural University
dc.research.problemProspecting plant growth promoting and endophytic bacteria for improving growth and yield of sunflower (Helianthus annuus L.)
dc.subMicrobiology
dc.themeProspecting plant growth promoting and endophytic bacteria for improving growth and yield of sunflower (Helianthus annuus L.)
dc.these.typeM.Sc
dc.titleProspecting plant growth promoting and endophytic bacteria for improving growth and yield of sunflower (Helianthus annuus L.)
dc.typeThesis
Files
Collections
Thesis