Field performance of three rhizobium japonicum strains with two soybean cultivars

ABSTRACT

A field experiment was conducted in a clay loam soil to study the performance of three R. japonicum strains; USDA 110, USDA 138 AND TAL 379; in relation to their N2 fixing potential and competitive relation on two soybean cultivars [Clark and Calland]. Inoculation of soybean cultivars with these strains either singly or in combination induced significant increase in plant dry weight, N2 fixation and seed yield, strain USDA 110 was the most efficient strain in N2 fixation and in increasing seed yield on both cultivars followed by USDA 138, while TAL 379 was the least effective strain. The two soybean cultivars were similar in their response to inoculation. No significant difference in seed yield were observed between Clark and Calland cultivars. The interaction between inoculant strain and soybean cultivar was not significant