Abstract:
The aim of this research is the Isolation and identification of nitrogen-fixing and
phosphorous-solubilizing soil bacteria associated with vegetable cultivation in the
'Karaitivu' area. The laboratory experiment was carried out in the Microbiology
laboratory Faculty of Technology, Eastem University from the period of March 2024 to
June 2024.Isolation of nitrogen-fixing and phosphorus-solubilizing soil microorganisms
was done using the azotobacter medium and pikovskaya's agar medium. Purified forms
of nitrogen-fixing and phosphorus solubilizing soil bacteria were isolated using NA media.
Accordingly, a total of 9 Nitrogen-fixing soil microorganisms (I{SICI, NSIC2, NSIC3,
NS2Cl, NS2C2, NS2C3, NS3Cl, NS3C2, NS3C3), and 9 phosphorous solubilizing soil
microorganisms (PSICI, PSIC2, PSIC3, PS2Cl, PSZCZ, PS2C3, PS3Cl, PS3C2, PS3C3)
were isolated from the home garden, organic farm, and inorganic farm in 'Karaitivu area'.
All the isolated microbes have rod-shaped cells. Nitrogen-fixing microbes and phosphorus
solubilizing microbes were isolated from various vegetable-cultivated soil samples (home
garden, organic farming, inorganic farming). A total 5 purified forms of nitrogen-fixing
bacteria (NSICa, NSlCb, NS2Ca, NS2Cb, NS3Ca) and 5 purified forms of phosphorous
solubilizing bacteria were selected to study (PS1Ca, PSlCb" PS2Ca, PS2Cb, PS3Ca) the
morphology further. All the purified bacteria were found to be gram-positive (purple
color) in the gram-staining test. Gram status was observed under the fluorescence
microscope.
Morphological characterization results showed in terms of colony characteristics (color,
form, elevation, margin, colony numbers) and cell characteristics (Gram status).
Morphological characteristics were observed by Stereo microscope. Further study is
required to examine the impact of these nitrogen-fixing and phosphorous-solubilizing
bacterial isolates on the yield before application as a biofertilizer.
