Biological Control of Botrytis cinerea: Interactions with Native Vineyard Yeasts from Washington State

Abstract

Native yeasts are of increasing interest to researchers, grape growers, and vintners because of their potential for biocontrol activity and their contributions to the aroma, flavor, and mouthfeel qualities of wines. To assess biocontrol activity, we tested 11 yeasts from Washington vineyards, representing isolates of Candida saitoana, Curvibasidium pallidicorallinum, Metschnikowia chrysoperlae, M. pulcherrima, Meyerozyma guilliermondii, Saccharomyces cerevisiae, and Wickerhamomyces anomalus, for ability to colonize Thompson Seedless grape berries, inhibit the growth of Botrytis cinerea in vitro, and suppress disease symptoms on isolated berries. The yeast-like fungus Aureobasidium pullulans was also included based on its known biocontrol activity against B. cinerea in studies on apple and grape. All yeast strains multiplied rapidly in grape berries and reached densities of over log 6 cells per wound as early as 2 days after inoculation with 200 cells. One of the Botrytis isolates used in this study was much less virulent than the others and was provisionally identified as B. prunorum based on multilocus sequence analysis. Suppression of the growth of B. cinerea isolates 111bb, 207a, 207cb, and 407cb occurred on berries treated with A. pullulans P01A006, Metschnikowia chrysoperlae P34A004 and P40A002, M. pulcherrima P01A016 and P01C004, Meyerozyma guilliermondii P34D003, and S. cerevisiae HNN11516. Inhibition of Botrytis isolates by the yeast strains was more common on berries than in vitro, suggesting the possibility that niche competition was a more likely biocontrol mechanism than antibiosis in planta. Metabolic profiling of yeast strains and B. cinerea isolates using Biolog YT plates revealed seven distinct metabolic groups. Furthermore, the yeast strains showed partial to complete tolerance to the commonly used fungicides fluopyram, triflumizole, metrafenone, pyraclostrobin, and boscalid. Implications of these findings for field deployment of native Washington yeasts as biocontrol agents against B. cinerea are discussed.

Differential Tissue-Specific Jasmonic Acid, Salicylic Acid, and Abscisic Acid Dynamics in Sweet Cherry Development and Their Implications in Fruit-Microbe Interactions

“…Additionally, different Aureobasidium isolates were recurrently found. Previous reports have described the biocontrol ability of certain Aureobasidium strains against certain postharvest decay pathogens like B. cinerea, but other strains can behave as opportunistic pathogens in apples and sweet cherries (Kim, 2014;Wang et al, 2018). Altogether, our data confirmed that fungal post-harvest decay pathogens were already present at the field not only prior to harvest, but also at very early stages of fruit development.…”

Increased Organic Fertilizer and Reduced Chemical Fertilizer Increased Fungal Diversity and the Abundance of Beneficial Fungi on the Grape Berry Surface in Arid Areas

“…The epiphytic fungi living in plant tissues, particularly Aureobasidium (Ferreira-Pinto et al, 2006), Candida (Mewa-Ngongang et al, 2019), and Pichia (Mewa-Ngongang et al, 2019, play essential roles in disease control. Aureobasidium pullulans was used as a biocontrol agent against B. cinerea on grapes (Wang et al, 2018a). Certain fungal genera enriched in the B.O and A.O samples have been reported to exhibit protective functions.…”

The Role of Yeasts as Biocontrol Agents for Pathogenic Fungi on Postharvest Grapes: A Review

“…In particular, P. kluyveri strain SEHMA6B has shown to be more effective against B. cinerea than the synthetic fungicides. Moreover, in 2019, Carmichael et al [ 81 ] evaluated the abundance and the diversity of yeast populations already known as natural antagonists of postharvest pathogens ( Aureobasidium , Cryptococcus , Rhodotorula , and Sporobolomyces ), with a particular focus on their action against B. cinerea , in the different phenological stages of table grapes (variety crimson seedless). The results of this study showed that a high presence of populations of possible biocontrol yeasts was associated with a low prevalence of pathogenic groups.…”