Introduction: Azomonas agilis, a nitrogen-fixing bacterium, was isolated from rhizospheric soil in central Myanmar.Methods & Materials: The nitrogen-fixing activity of this bacterium was detected by plate screening method using glucose nitrogen free mineral medium and ammonium test-kit Cellulolytic activity was screened by plat assay and detected by Dinitrosalicyclic acid method (DNS).Results & Discussion: The isolated A. agilis grew in media containing 3-12% of NaCl, although the growth became poor when NaCl concentrations increased. Among various carbon sources, sucrose was the best source for ammonium accumulation of this bacterium, whereas arabinose was not the suitable carbon source. Although the nitrogen-fixing activity of A. agilis was highest after one week incubation, cellulase enzyme production was highest after 2-3 days of incubation. It was observed that cellulase enzyme activity of A. agilis for cellulose and sodium carboxymethyl cellulose (CMC) was almost the same. Three agricultural wastes were used to detect the cellulase enzyme activity of A. agilis, cellulase activity was better on filter paper as a substrate when compared to rice-straw and sawdust.Conclusion:So, the isolated A. agilis has high potential as an effective bacterial strain to use in sustainable agriculture and degradation of some agricultural residues.

In this study, 13 bacteria were isolated from the agricultural soils of Kyaukse city, Myanmar, and out of these isolates, two bacteria isolates viz. JU-24 and JU-33 are found to be potent phosphate (P) solubilisers and are selected for further studies. These two isolates are identified as Bacillus megaterium based on the 16S rRNA gene sequence. When the growth rates of these two isolates were tested for salt tolerance, they could grow well in media with NaCl concentrations of 3%, 6% and 9%. For 0% and 3% NaCl concentrations, JU-33 (84.37 mg/L for 0% NaCl and 130.36 mg/L for 3% NaCl) showed higher P-solubilising efficiency than JU-24 (73.29 mg/L for 0% NaCl and 87.42 mg/L for 3% NaCl) for both NaCl concentrations when inoculated in Ca3(PO4)2 containing liquid medium. In media containing AlPO4 and FePO4 without NaCl, the P-solubilising activity of JU-24 is higher than JU-33 for these two substrates. Moreover, these strains showed noticeable levels of P solubilisation activity in the presence of various carbon sources indicating high P-solubilising efficacy. The soil inoculation experiment revealed that inoculating the experimental soil with JU-33 resulted in an obvious increase in available P, which increased from 13.08 mg/L in the non-inoculated soil to 18.40 mg/L in the inoculated soil with the bacterial isolate, JU-33. This study clearly showed that JU-24 and JU-33 isolates could be used as biofertilizers in ecological agricultural systems and may help to sustain environmental health and soil productivity. The use of biofertilizers can reduce the use of expensive chemical fertilisers, reducing planting costs and improving soil fertility through long-term use. Biofertilizers can help solve the problem of feeding an increasing global population at a time when agriculture is facing various environmental stresses and are affordable for low-income farmers.

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Several nitrogen-fixing bacteria were isolated from the agricultural soil samples of Kyaukse District, Mandalay Division, Myanmar. Among the isolated strains K-3 and T-7 were identified as Azotobacter beijerinckii and Azotobacter vinellandii and and M4 was identified as Stenotrophomonas maltophilia.. Although other studies have reported that wild types of the nitrogen-fixing bacteria cannot produce excess ammonia, our experiments indicated that these three strains accumulate relatively high amounts of ammonia in medium with a low concentration of sugar. Azotobacter beijerinckii accumulated approximately 0.48 mM of ammonia after incubation for 96 hour in 0.5% nitrogen free glucose mineral medium (NFGMM), while A. vinelandii accumulated approximately 0.36 mM in 0.25% nitrogen free fructose mineral medium (NFFMM) after 96 hour. Stenotrophomonas maltophilia accumulated highest amounts of ammonia in glucose supplemented medium approximately 0.52mM after 96h incubation. A. beijerinckii also accumulated ammonia in fructose, galactose, and sucrose media. Azotobacter vinelandii accumulated ammonia mainly in fructose and Stenotrophomonas maltophilia accumulated ammonia in glucose, sucrose and mannitol. In this research work, it was noted that ammonia began to accumulate when no sugar remained in the medium, therefore we suggested that carbon source plays a key role in ammonia accumulation.

Rhizospheric bacteria are naturally occurring soil microbes that are aggressively found in the plant rhizosphere, at root surface and in association with roots. They give satisfactory benefit plants by several mechanisms such as nitrogen fixation, phosphate solubilization, potassium decomposition, IAA production, antagonism against phytopathogenic microorganisms by production of siderophore, antibiotics and cell wall degrading enzymes. The total number of beneficial bacteria were isolated from different rhizospheric soil in agricultural lands. The isolated bacterial strains were screened for their plant growth promoting factors such as production of ammonia, siderophore, cellulase, chitinase, and pectinase enzyme. All of the isolates produced ammonia and 79% of the isolates produced siderophore on chrome azurole S agar plates. Furthermore, the bacterial isolates produced cell wall degrading enzyme; pectinase (69%), cellulase (94%), chitinase (51%), amylase (61%) and glucanase enzyme (59%) on agar plate method. The isolates also produced auxin type plant hormone (IAA), all the isolates produced IAA and the highest IAA producing strain is W1 and the produce amount was 21.91mg/L. Among the isolated bacteria, only two strains could produce HCN with the use of Feigl-Anger paper method. The recent study suggests that the use of these PGPR isolates as inoculants might be a promising source for sustainable agricultural use.