YIELD RESPONSE OF BEAN TO DIFFERENT AGRICULTURAL PRACTICES AND MICROBIAL ACTIVITY IN ITS RHIZOSPHERE.

The aim of this study was to compare the effect of organic and conventional production on yield parameters of bean (Phaseolus vulgaris) as well as on the number of rhizospheric microorganisms. Studies were conducted at two sites on chernosem soil. Organic production was conducted on the field in the village Pivnice, while conventional production was conducted in the village Čurug, Serbia during 2014. Varieties of Balkan, Zlatko, Belko, Sremac, Slavonac, Maksa, and 20-tica were used. Before sowing, the bean seeds were inoculated by biofertilizers NS-Nitragin for beans and faba beans. NS-Nitragin contains a mixture of selected strains of symbiotic bacteria Rhizobium leguminosarum bv. phaseoli. Laboratory measurements were performed in microbiological laboratories of Faculty of Agriculture, Novi Sad and in the Institute of Field and Vegetable Crops, Novi Sad. The height and mass of the plant, the number and weight of the bean seeds per plant as well as the number of microorganisms in its rhizosphere (the total number, number of azotobacter, actinomycetes and fungi) were determined. In this research, the average values of all examined parameters of plant yields were lower in the organic production compared to conventional, except for variety Slavonac. In this case it was obtained a statistically significant increas of plant mass, number and weight of seeds per plant in organic production compared to conventional. Those results indicate that the variety Slavonac should be grown in organic production. The results showed that inoculation can have a positive effect on the number of microorganisms in the rhizosphere of the bean. The number of the investigated groups of microorganisms, apart from actinomycetes, increased in the organic production, where microbiological fertilizers were applied. In average, statistical analises showed that inoculation did not have a statistically significant impact on the number of the investigated groups of microorganisms. [ABSTRACT FROM AUTHOR]