Semi-commercial testing of native yeasts selected from north patagonia argentina for the biocontrol of pear postharvest decays

CECILIA LUTZ, MARÍA; ARIEL LOPES, CHRISTIAN; CRISTINA SOSA, MARÍA; PAULA SANGORRIN, MARCELA

BIOLOGICAL CONTROL

ACADEMIC PRESS INC ELSEVIER SCIENCE

Año: 2020

1049-9644

The efficacy of two regional yeasts, Pichia membranifaciens NPCC 1250 and Vishniacozyma victoriae NPCC 1263,for controlling pear postharvest decay was evaluated at large scale (semi-commercial conditions) in two differentpacking houses. The human safety of the two yeasts strains was initially assayed by assessing growth at body temperature,pseudohyphal growth, phospholipases production, and growth in simulated gastric juice. Subsequently,yeasts biomass was produced in a bioreactor (20 L) containing 18 L of culture medium based on sugarcane molassesplus plus urea. The produced biomass, with/without CaCl2 (2% w/v) addition, was used in biocontrol experimentscarried out at semi-commercial scale on Beurre d'Anjou and Packham's Triumph pear. Vishniacozymavictoriae NPCC 1263 plus CaCl2 showed high performance on controlling decay caused by Penicillium expansumand Botrytis cinerea. On Beurre d'Anjou cvs, P. expansum and B. cinerea incidence was reduced by 70% and 100%,respectively, after 90 days of commercial storage. On Packham's Triumph the incidence of the two decay formswas 63% after 150 days. The two antagonistic yeasts were able to establish and colonize the surface of the fruit,with an estimated increase in the population density of approximately three orders of magnitude during thepostharvest period. This work is the first to evaluate and demonstrate the efficacy of local biocontrol experimentswith regional yeasts under semi-commercial conditions.,