Biotechnology of biological bacterial preparations used in resource-saving farming

Abstract

The article presents materials on the use of selenium compounds in the production of biological fertilizers, the main active component of which being artificially cultivated nodule bacteria. The objects of research in this work were various types of bacterial organisms used to prepare bacterial fertilizers: symbiotic nitrogen-fixing bacteria (rhizoagrin, rhizotorfin for galega and pea) and free-living agrobacteria (agrophil). Sodium selenate (Na2SeO4) was used as a source of selenium. The most optimal concentration of selenium ions in the liquid culture of microorganisms was 10–4 g/kg. A positive effect of selenium on the titer of finished preparations was observed: on average for the study period Rhizobiumpisum (rhizotorfin for peas) and Agrobacter 10 (agrophil) on the variant with selenium exceeded that on the control variant by 35.2 and 26.6%, respectively. The absolute titer values of the finished preparations Rhizobiumpisum (pea rhizotorfin) and Agrobacter 10 (agrophil) on non-sterile peat turned out to be higher than on sterile peat, although the trend remained. The inoculation of pea seeds with bacterial preparations increased the number of nodules in the flowering phase on the roots of pea plants by 1.8–2.1 times compared with the control. The treatment of pea seeds with rhizotorfin activated by selenium compounds during its manufacture increased the grain yield by 0.51 t/ha (17.1%) compared with the control, and by 0.30 t/ha (10.0%) when inoculated with rhizotorfin.