Biochemical Characterizations of Selected Indigenous Endophytic Bacteria Potential as Growth Promoters and Biocontrol Agents on Tomato

Abstract

Nine indigenous endophytic bacteria strains showing the best ability to promote growth and control tomato pathogens had been screened in our previous research. The strains’ biochemical properties, such as nutrition and other traits, must be characterized to design the best formulations for the strains’ biochemical properties. This study aimed to describe the biochemical characteristics of the selected indigenous endophytic bacteria. The variables observed were utilization of carbon sources (glucose, fructose, sucrose, lactose, glycerol, and olive oil), nitrogen sources (peptone, yeast extract, urea, NH4Cl, NH4SO4, and NH4NO3), and citrate, hydrolytic activities (urease, triple sugar iron, starch hydrolysis, gelatin hydrolysis, chitinase, cellulase, protease, lipase, and catalase), oxidative/fermentative assay, salt tolerance, and growth ability at 4° and 44°C. This study showed that all the endophytic bacteria strains characterized had various biochemical characteristics. All strains showed the different ability to utilize nitrogen and carbon source. Some strains survived to grow at 4°C except Bacillus cereus AGBE 1.2 TL. All strains tolerate growth in 4% NaCl concentrations, while some strains can tolerate up to 6%. This result can be used for further studies to develop the most suitable formulations for each strain to get the best results of the growth-promoting and biocontrol activities of the indigenous endophytic bacteria strains.