Azospirillum brasilense promotes terpene cyclase activity under stress by NaCl

COHEN A; GIL M; PICCOLI P

Congreso; XVII Jornadas Científicas de la Sociedad de Biología de Córdoba; 2007

SBC

Azospirilllum brasilense are plant growth promoter bacteria (PGPB) that improve yield in cereals and others species. The beneficial effects of PGPB are attributed to production of terpenic phytohormones like ABA. ABA production by A. brasilense in chemically-defined media was doubled when 100 mM NaCl was added to the medium. In stressed plants FPP is cyclized by sesquiterpene-cyclases (TPS) to produce phytoalexins. The aim of this work was to evaluate sesquiterpene-cyclase activity in A. brasilense cultures with NaCl. Bacteria were cultured in NFB medium fed with 3H-FPP. Addition of 100 mM NaCL enhanced 40-fold the proportion of radioactivity related with terpene cyclase activity. These results suggest that A. brasiliense elicitate synthesis of sesquiterpene phytoalexin-like compounds under NaCL stress conditions