Influence of rhizotorfin on development of soybean cultivars released by the Siberian Research Institute of Agriculture at the irrigation in the southern forest-steppe of the Western Siberia

The researches were conducted in 2011-2014 on the irrigated stationary plot of the Siberian research institute of agriculture in the southern forest-steppe of the Western Siberia. The purpose was to study features of productional process of soybean and identification of a role of seeds inoculation by rhizotorfin in realization of its biological potential. Three early soybean cultivars - Eldorado, Dina and Zolotistaya -were studied. It is revealed that safety of soybean plants in average in the trial was high - 94.5% and did not depend on a cultivar or rhizotorfin application. This mehtod had no impact on seed productivity - 2.07 t per ha (control) and 2.02 t per ha (rhizotorfin), but positive action of a bacterial preparation on indicators of symbiotic activity of soybean was distinguished - average weight and quantity of tubercle on its roots was 4.39 g and 120 pieces per 10 plants respectively, that means enlargement by 161 and 100% in comparison with control variant. Application of rhizotorfin significantly increased protein content in seeds of all studied cultivars from 36.95 to 38.74%, or on 1.79%, in average for four years. Thus, the result of long-term studying of three soybean cultivars of SibNIISKh breeding in contrast weather conditions under an optimum level of moisture and the lowered nitrogen content in soil, and lack of native strains of nitrogen fixing bacteria showed that rhizotorfin application caused simbiotrophic nutrition of soybean plants. This influenced on increasing of weight and quantity of tubercles on roots and protein content in seeds. The pre-sowing seed inoculation by rhizotorfin didn't have a positive effect on safety of plants, yield, and protein and fat contents of seeds.