BRADYRHIZOBIUM JAPONICUM A PLANT GROWTH PROMOTING BACTERIA OF RICE

REPARAZ J.M; BEZUS R; GAUNA M; MARTINEZ ALCÁNTARA V; LOPEZ S.M; DEGRASSI G; BALATTI P.A

Congreso; X encuentro latinoamericano y del caribe de biotecnología agropecuaria y XI simposio redbio argentina; 2019

Redbio

Rhizopheric bacteria might promote plant growth and they are known as plant growth-promoting rhizobacteria (PGPR). They establish different types of interactions with plants thatdirectly or indirectly promote plant growth and development. Among other things, these bacte-ria might also indirectly inhibit the development of phytopathogens. On the other hand, plantgrowth promotion might be due to nitrogen fixation, phosphate solubilization, production ofhormone-like molecules, enzymes and siderophores. Bradyrhizobium is a soil PGPR that fixesnitrogen within nodules developed mainly by members of the Fabaceae. We evaluated theability of several isolates of Bradyrhizobium japonicum to promote growth of rice plants (Oryzasativa) both under controlled conditions and also in field trials. In the lab rice seeds weresurface sterilized and then they were soaked in Bradyrhizobium cell suspensions of 1 x 108bacteria ml-1. Plants were grown for 35 days and then plant growth was measured by means ofplant length and dry weight. Field tests were conducted with two rice varieties Yeruá La Plataand Gurí INTA that were inoculated with three Bradyrhizobium strains selected based on theresults of laboratory tests. All inoculated plants performed better than uninoculated controls,however only strain 85 yielded independently of the cultivar, 1000 kg/ha that is significantlymore than uninoculated controls. Evidently, Bradyrhizobia promoted not only plant growth butalso yield though we still need to know the mechanisms involved