Y Zapata, A Díaz, E Grijalba, F Rodríguez, AM Cotes

The use of naturally occurring yeasts as biocontrol agents has attracted special interest because of their special attributes, nevertheless it has been recognized that the efficacy and consistent performance of such agents are affected by different factors. In order to select a biocontrol agent for controlling gray mold, 23 indigenous phyllosphere yeasts were tested accordingly to different criteria, as biocontrol activity and adherence on rose petals, tolerance to UVB radiation and growth by micro-fermentation. Results showed that all the evaluated yeasts significantly reduced gray mold development down from 17 to 64% and severity down from 2.5 to 30.0%, in comparison with the untreated control (100%). Yeast adherence ranged from 55 to 99%. Thirty percent of the tested yeasts showed less than 45% growth inhibition after UVB radiation exposure. With respect to the maximum specific growth rate in micro-fermentation …