SEMI-COMMERCIAL SCALE TEST OF PACKAGING PEARS WITH VISHNIACOZYMA VICTORIAE, YEAST SELECTED AS A BIOLOGICAL CONTROL AGENT

GORORDO, M.F.; LUCCA; ME; SANGORRIN, MARCELA PAULA

Congreso; XV SAMIGE Meeting; 2020

Pears, as a perishable product, require cold storage for long-term preservation to regulate supply. However, throughout this conservation the fruit is susceptible to different fungal diseases, caused mainly by Botrytis cinerea and Penicillium expansum, therefore, Biological Control is an alternative for the substitution of fungicides, with advantages for environmental sustainability and organic fruit production. V. victoriae was selected in a previous work because of its biocontrol effectiveness against postharvest pears diseases in commercial scale and in situ assays, protected under patent INPI No.: 20120101053.In this work, the yeast biomass was produced from different culture medium, using cheese-whey powder (CWP), cider residue (CR), salts and vitamins, with the intention of replacing expensive inputs. Fermentations were carried out in batch reactor (12 L), the CFU/ml and quality of the yeast biomass were evaluated.The V.victoriae biomass was evaluated through semi-commercial-scale assays in a packaging line of pears, spraying 108 cel/mL over 1400 pears. For this, the incidence and disease control percentages caused by phytopathogenic fungi are determined. The biomass both fresh and lyophilized was evaluated and control percentages of fresh and dehydrated biomass grown in SQP were compared. On the other hand, the fresh biomass grown in SQP and RS was compared. Treatments were conserved postharvest in cold rooms (-1/0 ° C and 95% RH) for 5 months. These tests will establish an ideal condition for the development of fresh and dehydrated biomass.Packham´s Triump was the variety tested on a semi-commercial scale. After 120 days, the fresh yeasts grown in CWP provided a control percentage of 58% for the disease caused by P. expansum and 47% for the disease caused by B. cinerea, while the freeze-dried yeasts achieved 65% control at P .expansum and 15% at B.cinerea. On the other hand, the yeasts grown in CR, obtained a control percentage of 88% for the disease caused by P. expansum and only 6% for the disease caused by B. cinerea.Finally, during the cold storage period, the yeast´s ability to grow on the pear surface was evaluated, showing that it is capable of reproducing under these conditions. In the future, V.victoriae could be used as a biocontrol agent in postharvest diseases during the conservation of organic production of pears in our productive region, the Norpatagonica.