Effect of rhizobium biofertilizers on main characteristics and yield of soybean

Abstract

The aim and tasks of the study. New rhizobium biofertilizers from nodule bacteria will improve nitrogen fixation of soybean. Thus, they will enhance yield capacity, reduce the groundwater leaching of nitrogen and other nutrients in rivers, improving the ecological situation.

Materials and methods. Rhizobium biofertilizers GF₅ and GF₆ and soybean cultivar Heinong 46 were the test material. The experimental variants: application of rhizobium biofertilizers GF₅ and GF₆, control. Plant height, green plant weight, root nodule number per root, nodule weight were measured in 10 plants at the beginning of flowering, at the peak of flowering and at the seed filling stage for each experimental variant. Soybean seed yield was determined after ripening.

Results and discussion. The study found that rhizobium biofertilizer GF₆ significantly increased the plant height, green plant weight, nodule number per root, and nodule weight as compared to the control. In particular, the plant height was improved by 1.0% at the beginning of flowering, by 3.0% at the peak of flowering, and by 3.5% at the seed filling phase. The green plant weight was improved by 12.7%, 4.2% and 21.2%, respectively; the nodule number - by 35.4%, 23.7% and 17.6%, respectively; the nodule weight – by 26.3%, 52, 6% and 62.8%, respectively.

Rhizobium biofertilizer GF₅ did not improved performance at the initial stage of flowering. Some improvement was seen as compared  the control at other phases, but it was smaller than that with rhizobium biofertilizer GF₆. GF₆ also more significantly affected the pod and seed numbers than GF₅.

Conclusions. Rhizobium biofertilizer GF₆ had more significant effects on all the parameters than GF₅. Thus, nodules are more competitive, and the efficiency of nitrogen fixation is higher with GF₆. This can significantly increase soybean yields.