Fungal endophytic communities associated to the phyllosphere of grapevine cultivars under different types of management

Abstract

a b s t r a c tFungal endophytes present in different asymptomatic grapevine plants (Vitis vinifera L.) located in different vineyards within Alentejo, a highly important viticulture region in Portugal, were identified in this study. Sampled grapevine plants included the three most representative cultivars in the region, Syrah, Cabernet Sauvignon, and Aragonez, growing under two different modes of management, conventional and biological. Sixteen fungal taxa were identified through sequencing of the internal transcribed spacer region. Total number of endophytic fungi isolated showed significant differences both in management mode and in cultivars, with higher numbers in grapevines under conventional mode and from Syrah cultivar. The composition of fungal endophytic communities did not show significant differences among cultivars, but differences were observed between fungal communities isolated from grapevines under biological or conventional modes. The most fungal taxa isolated from grapevines cultivated under biological mode were Alternaria alternata, Cladosporium sp., and Nigrospora oryzae, and under conventional mode Botrytis cinerea, Epicoccum nigrum, and Epicoccum sp. These differences suggest that the different products used in grapevine production have impacts in fungal endophytic composition. Further investigation of the identified fungi with respect to their antagonistic characteristics and potential use in plant protection to ensure food safety is now in course.

Inferred microbial networks lack replicability: consequences for next-generation biomonitoring

“…Community-level analyses showed that the richness, diversity and evenness of the grapevine foliar microbiota were significantly higher in organic than conventional vineyards, consistent with the recent findings of Kernaghan et al (2017) (but see Castañeda et al, 2018). The cropping system also significantly affected the composition of grapevine foliar fungal communities, as reported in previous studies Pancher et al, 2012;Varanda et al, 2016;Kernaghan et al, 2017;Castañeda et al,, 2018). Several fungal taxa differed significantly in abundance between cropping systems.…”

Endophytic fungal communities of Polygonum acuminatum and Aeschynomene fluminensis are influenced by soil mercury contamination

“…These genera are frequent for endophytic fungi from areas contaminated with heavy metals [17,19,20,57]. Although usually considered a plant pathogen [78], species of genus Colletotrichum are frequently endophytic in foilar tissues [20,65,73,79] and less frequently in root tissues [79]. However, in our study isolates of Colletotrichum were abundant, possibly because these strains are important to alleviate the stress caused by mercury.…”

“…Several factors affect the composition and structure of endophytic fungi, such as salinity [29], soil management [65], climate [66] and host [67]. In the same way, the presence of contaminants, such as heavy metals, are important parameters in structuring the fungal community [12,17,68].…”

An indigenousSaccharomyces uvarumpopulation with high genetic diversity dominates uninoculated Chardonnay fermentations at a Canadian winery

“…A. pullulans is a ubiquitous environmental yeast-like fungus that is commonly associated with grapes and vineyards [44,58,59], and was also the most common fungal species identified at the cold settling stage in must from Vineyard 8 two years prior to this current study [12]. E. nigrum is an endophytic fungus that has been previously identified in wine regions such as Italy, Portugal, and Spain [60–62]. Because both A. pullulans and E. nigrum are typically associated with vineyard environments, they have been proposed as potential biological control agents against grapevine pathogens [63].…”