The basic activity of Microbial Supplements Section is utilization of soil microorganisms for optimal production of field and vegetable plant species.
The research includes microbiological activity monitoring and application of beneficial and effective microorganisms as inoculants. Theoretical and experimental research was transferred into practice in the form of several commercial microbial supplements and patents for production of microbiological fertilizers.
A large portion of research in the previous period related to monitoring of microbiological activity (abundance and enzymatic activity) as indicators of mineral fertilizers application, soil management, pesticides, high presence of heavy metals, deformations due to soil compaction, etc. Microbiological features are important for characterisation and fertility evaluation of soils used for field and vegetable crops.
A large portion of research in the previous period was related to symbiotic N-fixation between Rhizobium / Bradhyrhizobium nodule bacteria and legumes. Seed inoculation by nodule bacteria enables significant increase in legume quality, grain yield and biomass. Additionally, it substantially decreases the application of pricy nitrogen fertilizers (up to 70%), which affects soil ecological balance with significant economic benefits. The research in this field was mostly connected to the symbiosis between nodule bacteria and soybean. By inoculating different soybean genotypes by nodule bacteria, it was determined that N-fixation effectiveness also depends on the genotype, which accentuates the need of simultaneous breeding of plants and nodule bacteria.
Asymbiotic N-fixation and coinoculants
Diazotrophs, N-fixing asymbiotic bacteria and phosphorus-mobilizing microorganisms can be an alternative and/or addition to mineral fertilizers in the production of field crops. Inoculants with asymbiotic N-fixing bacteria (Azotobacter, Azospirillum) alone and in mixture with Bacillus megaterium have shown beneficial effect in the production of non-legume plants, such as maize, wheat, sugar beet, potato and many vegetable crops. Research on the application of asymbiotic N-fixing bacteria as biofertilizers in the production of most important field crops (wheat, maize, sugar beet and sunflower) shows the possibility of fixing 20 to 60 kg of nitrogen per hectare, depending on the strain. Inoculating plants with asymbiotic diazotrophs and phosphorus-mobilizing microorganisms significantly increases yield, seed germinability and technological quality of field and vegetable crops.
Scientific achievements from the field of microbiologically assisted plant production in the previous period (16 monographs, several hundred research papers and reports at national and international scientific events) are transferred into practice through several microbial supplements and patents for microbiological fertilizers production.
“Procedure for the production of microbiological fertilizer” (patent number 48985) was patented by Intellectual Property Department (Belgrade, Serbia) in 1995. Theoretical and experimental achievements aided the production of several commercial microbial supplements – biofertilizers used for legume production (NS Nitragin for soybean, NS Nitragin for string beans and beans, NS Nitragin for peas, NS Nitragin for alfalfa) as well as NS Betafixin recommended for sugar beet production.
The supplement NS Nitragin for soybean has been introduced in soybean production process as an obligatory measure. In the last several years, it has been produced for 120.000 – 140.000 ha annually.