Screening for indole-3-acetic acid synthesis and 1-aminocyclopropane-carboxylate deaminase activity in soil yeasts from Chile uncovers Solicoccozyma aeria as an effective plant growth promoter

Abstract Background and aims Plant growth-promoting microorganisms (PGPMs) stimulate plant growth by a series of mechanisms, including atmospheric nitrogen fixation, phosphorus solubilization the synthesis hormones. Within group PGPMs, several species bacteria fungi have been extensively studied. However, little information is available with regard to soil yeasts. The present study was conducted identify yeast strains isolated from different soils in Chile that promotion activity. Methods Twenty-three were evaluated either for their capacity synthesize indole-3-acetic acid or show aminocyclopropane-1-carboxylate deaminase effect on tomato seedling vitro , two selected vivo evaluation root ethylene synthesis. Results All analyzed presented IAA within range between 0.8 3.3 ?g mL ?1 . Solicoccozyma aeria (YCPUC75 YCPUC79 strains) only ACC In inoculation seeds eight resulted an increase volume number lateral roots. second experiment, 40% reduction achieved adding S. (YCPUC79) zone, which 26% growth. Conclusions effective promoter stimulating reducing