Two field experiments were conducted at Sakha Agric. Res. Station during
the two successive seasons 2000 and 2001 to measure the symbiotic performance of
Bradyrhizobium japonicum (St 1577, RJG and SSG) when used to inoculate soybean
seeds in combination with mineral N2-fertilization (60 kg N/fed.) and two foliar sprays,
each of which contains different quantity and quality of macro and micronutrients. Results were recorded after 45 and 80 days of planting time. The
uninoculated treatments exhibited the lowest number of nodules on soybean roots,
because the soil under investigation could be consider free of native rhizobia. It is,
therefore of vital importance to continue inoculation of soybean seeds with effective,
competitive and persistent strains of soybean rhizobia inoculation of soybean
enhanced in general nodule formation, growth of nodular tissue which reflects it is
effect on seed yield and their total N2 content. The improvement of nodulation and
biological N2-fixation was further strengthed by foliar spray especially with cornp, 2. In
the absence of rhizobial inoculation foliar application achieved less improvement in
seed yield and their total N, P and K.