title: Biological control of major postharvest pathogens on apple with Candida sake.
abstract: Epiphytic microorganisms isolated from apples, pears and the surfaces of apple leaves were screened for antagonistic activity against Penicillium expansum (blue-mold), Botrytis cinerea (gray-mold) and Rhizopus nigricans (Rhizopus rot) on apple (Malus domestica). A total of 933 bacteria and yeasts were tested in primary screening against P. expansum. Ninety-two strains reduced the lesion size on apples by more than 50%, 72 of which were isolated from the surface of apples. For secondary screening against P. expansum, B. cinerea and R. nigricans, 31 strains were selected. The most promising isolate, CPA-1, was identified as Candida sake. This yeast, isolated from apples in storage season was very effective against all three diseases. Wounded Golden Delicious apples protected with the yeast suspension at a concentration of 2.6 x 10(6) CFU/ml and inoculated with conidia of B. cinerea and R. nigricans of 10(5) and 10(4) conidia/ml, respectively, did not develop rot. Complete control of P. expansum was obtained at the same concentration of the antagonist with a pathogen inoculum concentration of 10(3) conidia/ml. This strain, also provided excellent control of rot development under cold storage conditions. The strain of Candida sake can grow actively in aerobic conditions. In drop-inoculated wounds of apples, the populations of C. sake increased by more than 50-fold during the first 24 h at 20 degrees C. The maximum population of C. sake on apple wounds was the same at 20 as at 1 degrees C and was recovered after three and twenty days, respectively.
authors.affiliation: Postharvest Unit, CeRTA, Centre UdL-IRTA, Lleida, Catalonia, Spain. INMA@LLEIDA.IRTA.ES
authors.forename: I
authors.initials: I
authors.lastname: Viñas
authors.forename: J
authors.initials: J
authors.lastname: Usall
authors.forename: N
authors.initials: N
authors.lastname: Teixidó
authors.forename: V
authors.initials: V
authors.lastname: Sanchis
mesh_terms: D002175:Candida / Q000502:physiology*; D003080:Cold Temperature; D003904:Mitosporic Fungi / Q000502:physiology; D010407:Penicillium / Q000502:physiology; D010572:Pest Control, Biological; D012233:Rhizopus / Q000502:physiology; D019685:Rosales / Q000382:microbiology*