Symbiosis of selected Rhizobium leguminosarum bv. viciae strains with diverse pea genotypes: effects on biological nitrogen fixation

Biological nitrogen fixation (BNF) can be improved by optimizing the interaction between the rhizobial inoculant and pea (Pisum sativum L.), leading to increased productivity and reduced nitrogen (N) fertilizer use. Eight Rhizobium leguminosarum bv. viciae strains were used to inoculate super-nodulating pea mutant Rondo-nod3(fix+), hyper-nodulating pea mutant Frisson P88 Sym29, CDC Meadow commercial control, and a non-nodulating mutant Frisson P56 (nod-) to evaluate BNF in a greenhouse assay. Significant differences in strainĂ cultivar interactions were detected for shoot and root dry weight which ranged from 1.8 to 4.7 g and 0.27 to 0.73 g per plant, respectively, for nodule number on lateral roots which ranged from 25 to 430 per plant, for amount of fixed N, which ranged from 15 mg to 67 mg, and 4 mg to 15 mg per plant for shoot and root tissue, respectively, and for percentage of nitrogen derived from atmosphere (%Ndfa) which ranged from 37% to 61%, and 35% to 65% for shoot and root tissue, respectively. StrainĂ cultivar interactions in this study could contribute to identifying superior strains and pea breeding lines with genetic superiority in BNF. Nodule production in pea plants was not necessarily correlated with the amount of fixed N, suggesting nodule activity is more important to BNF than nodule number.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author