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

LUTZ M.C.; LOPES C.A.; SOSA M.C.; SANGORRÍN M.P.

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 1263native yeasts for pear controlling postharvest decay of pear fruits was evaluated at large scale (semi-commercialconditions) in two different packing houses. The human safety of the two yeast was initially assayed by assessinggrowth at body temperature, pseudohyphal growth, phospholipases production, and growth in simulated gastricjuice. Subsequently, yeasts biomass was produced in a bioreactor (20 L) containing 18 L of culture medium basedon sugarcane molasses plus. The produced biomass, with/without CaCl2 (2% w/v) addition was used in biocontrol experiments carried out at semi-commercial scale on Beurre d'Anjou and Packham's Triumph pear. Vishniacozyma victoriae NPCC 1263 plus CaCl2 showed high performance on controlling decay caused by Penicilliumexpansum and 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 twodecay forms was 63% after 150 days. The two antagonistic yeasts were able to establish and colonize the surfaceof the fruit, with an estimated increase in the population density of approximately three orders of magnitudeduring the postharvest period. This work is the first to evaluate and demonstrate the efficacy of local biocontrolexperiments with regional yeasts under semi-commercial conditions.