An inoculant developed using sulfur-oxidizing rhizobacteria with Rhizobium can enhance seed emergence, increase biomass and increase nodule numbers on legumes such as alfalfa, soybeans and peas, according to research from BrettYoung Seeds, Winnipeg, Manitoba.

Laila Yesmin, the seed company's director of research and development, used Delftia acidovorans strain RAY209, a PGPR (plant-growth-promoting rhizobacteria) Rhizobium, possibly the first PGPR-based inoculant developed for legumes.

Soybeans and peas that were inoculated with the PGPR and rhizobia showed significant increases in biomass and yield on soybeans and an increase in biomass in peas compared to plants inoculated with only rhizobia.

Alfalfa also showed “very promising results,” Yesmin says.