Yeasts associated with nectarines and their potential for biological control of brown rot

• Published in: Yeast (Chichester, England) England), 2010-07, Vol.27 (7), p.389-398
• Main Authors: Janisiewicz, W.J, Kurtzman, C.P, Buyer, J.S
• Format: Article
• Language: English
• Subjects: Antibiosis; Aureobasidium pullulans; Biodiversity; Biological control; biological control agents; Brown rot; brown-rot fungi; Candida; Citrus; Cluster Analysis; Cryptococcus; Cryptococcus (Hyphomycetes); Developmental stages; DNA, Fungal - chemistry; DNA, Fungal - genetics; DNA, Ribosomal - chemistry; DNA, Ribosomal - genetics; DNA, Ribosomal Spacer - chemistry; DNA, Ribosomal Spacer - genetics; food biopreservation; food biopreservatives; food pathogens; food spoilage; fruit microflora; Fruit rot; fruit set; fruit trees; fruiting; Fruits; Genes, rRNA; Genetic analysis; isolation; Microflora; Microorganisms; molecular systematics; Monilinia fructicola; Mycological Typing Techniques; nectarines; New species; new taxa; Orchards; Pest Control, Biological - methods; Phylogeny; Pichia; Plant Diseases - microbiology; Plant Diseases - prevention & control; postharvest biocontrol; postharvest diseases; postharvest food safety; Prunus - microbiology; Prunus persica; pullulan; Rhodotorula; RNA, Fungal - genetics; RNA, Ribosomal - genetics; rRNA; Sequence Analysis, DNA; Sonication; Sporidiobolus; Trees; Vitaceae; yeast communities; yeasts; Yeasts - classification; Yeasts - growth & development; Yeasts - isolation & purification
• ISSN: 0749-503X; 1097-0061; 1097-0061
• DOI: 10.1002/yea.1763

Resident fruit microflora has been the source of biocontrol agents for the control of postharvest decay of fruits and the active ingredient in commercialized biocontrol products. With the exception of grapes and apples, information on the resident microflora of other fruits is only fragmentary, but greater knowledge in this area can be very helpful in developing biocontrol strategies. We characterized the yeast microflora of nectarines ('Croce del Sud') from the early stages of fruit development until harvest. The fruit samples were collected from trees in an unmanaged orchard. The resident fruit microflora was separated from the occasionally deposited microorganisms by discarding initial fruit washings before the final wash, followed by sonication and plating on NYDA medium. The isolated yeasts were identified by BIOLOG and by sequencing the D1/D2 domain of a large subunit of the rRNA gene and, where available, the ITS sequence. BIOLOG identified 19 and the genetic analysis 23 species of yeasts. Although the identification by these two systems was not always the same, the predominant yeasts were Rhodotorula spp., Sporodiobolus spp., Cryptococcus spp., Pichia spp., Candida spp. and yeast-like Aureobasidium pullulans. Several of the taxa appear to represent new species. The preliminary biocontrol tests against brown rot of nectarine fruit caused by Monilinia fructicola indicates significant decay control potential of some of the identified yeast species, namely Cryptococcus magnus, Cryptococcus sp. nov., Sporidiobolus pararoseus, A. pullulans and Rhodotorula sp. nov. Copyright © 2010 John Wiley & Sons, Ltd.