Identification of grape berry indigenous epiphytic yeasts with <i>in vitro</i> and <i>in vivo</i> antagonistic activity towards pathogenic fungi

Abstract

During their lifespan, grapes are exposed to conditions that can endanger plant health, including fluctuating climate and infection by pests and insects. In particular, attacks by filamentous fungi represent huge annual losses for grape farmers. Present concerns about rising antimicrobial resistance, fungicide prohibitions and shifting consumer tastes are driving the search for less harmful ways of preventing damage to grapevine by pathogenic fungi. In this study, the antagonist activity of yeasts isolated from grape berry surface microbiota was assessed by in vitro and in vivo assays on an assortment of grapevine fungal pathogens, including Botrytis cinerea and Aspergillus niger. The results show that W. anomalus, A. pullulans, C. intermedia, R. glutinis, Z. meyerae and H. takashimae were able to inhibit by 75 to 100 % mycelia growth and sporulation of the filamentous fungi in vitro. Strains of M. pulcherrima and S. bacillaris also showed 50 to 75 % efficacy in reducing mould growth. The strains were further assessed on incised leaves of 2-month-old grapevines for their ability to reduce disease incidence by the filamentous fungi. W. anomalus, A. pullulans, M. pulcherrima, C. intermedia and R. glutinis significantly reduced infection symptoms in the leaves, indicating their potential as effective biocontrol yeasts in the vineyard.

The presence of a significant endophytic fungus in mycobiome of rice seed compartments

“…However, the seed epiphytes can become endophytes by entering the seed through the small pores of the seed coat, and vice versa [18]. Also, the epiphytes can provide the rst host defense against external pathogens and antagonize other species with in the microbial population [21,22]. Therefore, understanding the epiphytic and endophytic seed microbiome can be expected to provide insight into the formation and interactions of the seed microbiome [23,24].…”

On the Way to the Technological Development of Newly Selected Non-Saccharomyces Yeasts Selected as Innovative Biocontrol Agents in Table Grapes

“…Microbial fungicides, based on Biological Control Agents (BCAs), such as bacteria, yeasts, and molds, represent a valid alternative to chemicals for a safer and more effective control strategy [ 16 , 17 , 18 , 19 , 20 ]. Most of the BCAs described against post-harvest pathogens are non- Saccharomyces yeasts [ 21 , 22 , 23 , 24 , 25 ], because they offer advantages, such as simple nutritional requirements, the ability to colonize dry surfaces for long periods and the inability to produce allergenic spores or mycotoxins. In 1996, Rhodotorula glutinis (Fresen.)…”

Dynamic Succession of Natural Microbes during the Ecolly Grape Growth under Extremely Simplified Eco-Cultivation

“…There is a growing view that under favorable ecological conditions, the grape natural microbial ecosystem can remain relatively stable, and the dynamic and balanced interactions between microbes and between grapes and microbes can ensure growth health and material accumulation [16,17]. It has also been found that the presence and metabolic activity of certain organisms on the grape epidermis may antagonize other species, while bioactive molecules secreted by endophytic and phyllosphere yeasts can also replace the action of essential agrochemicals [18]. Moreover, natural yeasts may have biocontrol activity against filamentous fungi.…”