GROWTH CHARACTERISTICS OF PSEUDOMONAS PUTIDA STRAINS AND EFFECT OF HUMIC SUBSTANCES ON CELL DENSITY DURING BATCH CULTIVATION

V. Savov, Y. Evstatieva, T. Georgieva, Ts. Licheva, D. Nikolova

Abstract: In this work are studied three strains of genus Pseudomonas which were identified as Pseudomonas putida. Growth characteristics of the three strains are studied using two types of broth media. The dynamics of the growth of the microorganisms were recorded by the changes in the optical density at 590 nm. There is a lot of research proving the positive influence of Humic substances on the development of plants in combination with soil isolates such as Pseudomonas putida. Humic fractions (humic acid, fulvic acid) at concentration of 0.1 g/l stimulated the growth of the soil bacteria strains acting as a regulator of the
cell metabolism. In our experiments it is shown the influence of different concentrations of Humic fractions on the development of the test strains. It was found that there is a positive effect on the biomass density at the end of the batch cultivation at 2% as supplement of the media. For monitoring the biological effects of the studied strains is made test with Soybean and the seeds are treated with appropriate concentrations of the tested strains. This type of research is initial screening to monitor the activity of the strains, at all. It is used not only to monitor the germination of the seed but also for the entire development of the plants.

Keywords: Humic fractions; Pseudomonas putida

Date published: 2017-10-19