**5. Conclusion**

**Lectin concentration, µg/ml**

Relationships

74

modified with homologous lectin [80].

Note. I, II - 2005., III - 2006.

**Seed yield, cwt/ha**

0 36,2 ± 0,7 33,1 ± 1,8 22,5 ± 0,7 30,6 ± 1,1 – –

100 45,1 ± 1,4 41,2 ± 0,8 25,8 ± 1,1 37,4 ± 1,1 6,8 22,2

300 41,9 ± 1,5 38,8 ± 2,0 27,3 ± 1,0 36,0 ± 1,5 5,4 17,6

**Table 2.** Productivity of soybean inoculated with biological rhizobial preparation on the solid carrier (perlit) and

The economic efficiency of using bacterial preparations to inoculate the seeds of legume plants before sowing depends on the increase of yield, its cost and additional expenses. The calculation of economic efficiency of soybean production via a typical technological map was shown on a farm in the Kiev region (Table 3). By using bacterial preparations of soy‐ bean nodule bacteria (application of inoculation) the yield of the crop increased throughout Ukraine by an average of at least 12%, which makes it possible to increase the profitability of production to 27.8% (see Table 3). The use of bacterial preparations modified by homolo‐ gous lectin in the conditions of our field trials led to an increase in soybean yield of no less than 9.8% in comparison with conventional inoculation (see Table. 1 and 2). A comparative analysis of various indicators of economic efficiency of soybean cultivation points to the fea‐ sibility of using bacterial preparations to inoculate seeds (see Table 3). The profitability of production at the same time increased by 11.7%. The maximum profitability (39.2%) was ob‐ served when using bacterial preparations modified by homologous lectin, indicating the benefits of their use. Table 4 also shows that the use of bacterial preparations reduced pro‐ duction costs and increased net income. Thus, the cultivation of soybeans in the conditions and fields of Ukraine can produce about 0.4 hryvnia net profit to every 1 hryvnia spent. Therefore different preparatory forms of nitrogen-fixing microorganisms effectively increase the productivity of plants and can be recommended for agricultural production. The use of bacterial agents leads to a slight increase in the cost of production while the economic effect of using nitrogen-fixing bacteria is achieved due to the additional crop yield, the savings

**I II III**

A Comprehensive Survey of International Soybean Research - Genetics, Physiology, Agronomy and Nitrogen

LSD 0,05 4,2 5,1 2,5

made on fertilizers and the reduction of other production energy costs.

**Yield increment relative to control**

**cwt/ha %**

**Average of the 3 experiments**

> Given the uniqueness of the biochemical processes of nitrogen fixation by microorganisms and global importance of biological nitrogen fixation in the nitrogen cycle in the biosphere, this phenomenon requires further study and attention. Scientists still face the problem of finding new nitrogen-fixing communities, the creation of genetically engineered micro-and macro- symbionts, as well as studying specific mechanisms of the relationship between plants and microorganisms.

> A comprehensive study of plant-bacterial symbioses and associations made possible the use of biological nitrogen fixation in practice and opened up prospects for the management of this process. Work is presently being done on the generation, testing and introduction of new strains of *Rhizobium* and associative nitrogen fixers for the cultivation of plants in our latitudes. Among the promising works in the creation of biological preparations based on symbiotic nitrogen fixers are those regarding the creation of agricultural consortiums with cyanobacteria, the use of bacterial and synthetic polysaccharides, and plant lectins. The bio‐ logical preparations created based on beneficial microorganisms are an excellent alternative to mineral fertilizers. However, they have not yet been widely applied, which of course does not facilitate the resolution of a number of existing environmental and economic problems.
