Fungal Endophytes as a Metabolic Fine-Tuning Regulator for Wine Grape

Abstract

Endophytes proved to exert multiple effects on host plants, including growth promotion, stress resistance. However, whether endophytes have a role in metabolites shaping of grape has not been fully understood. Eight endophytic fungal strains which originally isolated from grapevines were re-inoculated to field-grown grapevines in this study, and their effects on both leaves and berries of grapevines at maturity stage were assessed, with special focused on secondary metabolites and antioxidant activities. High-density inoculation of all these endophytic fungal strains modified the physio-chemical status of grapevine to different degrees. Fungal inoculations promoted the content of reducing sugar (RS), total flavonoids (TF), total phenols (TPh), trans-resveratrol (Res) and activities of phenylalanine ammonia-lyase (PAL), in both leaves and berries of grapevine. Inoculation of endophytic fungal strains, CXB-11 (Nigrospora sp.) and CXC-13 (Fusarium sp.) conferred greater promotion effects in grape metabolic re-shaping, compared to other used fungal strains. Additionally, inoculation of different strains of fungal endophytes led to establish different metabolites patterns of wine grape. The work implies the possibility of using endophytic fungi as fine-tuning regulator to shape the quality and character of wine grape.

Epiphytic fungal community inVitis viniferaof the Portuguese wine regions

“…; Yang et al . ). Epiphytic fungi and bacteria play an important role in both grape health and quality.…”

Relevant responses in grape cells exposed to endophytic fungi or to fungal extracts at transcriptome and metabolome scopes

“…And these hyperdiverse communities of endophytes provided tremendous resources for crop managements as multiple standpoint. This will great interest to those crops given organoleptic sensitive products, such as grapevines, in which a ne-turned metabolic changes might trigger obvious quality and characteristic effects on the resultant wine [2,6]. Researches have covered the metabolic impacts of pure cultured fungal endophytes on grape cells under well controlled conditions in dual cultures, which appeared fungal strain, species and other taxonomical speci cities in shaping the metabolites of grape cells [7,9,10].…”

“…and CXC-13 (Fusarium sp. ),, exerting signi cant effects on grapevine metabolites [6]. Additionally, fungal strains could speci cally introduce novel metabolites into grape cells during a dual culture experiment, and these results implicated the possible of applying endophytes to improve physiologically and biochemically the qualities of grapevines [7].…”

Isolation and efficacy of the endophytic fungus, Beauveria bassiana (Bals.) Vuillemin on grapevine aphid, Aphis illinoisensis Shimer (Hemiptera: Aphididae) under laboratory conditions

“…These endophytic fungi have negative effects on different insect pests and plant pathogens by producing toxic compounds or by modifying the host plant defense response to enable pest and pathogen resistance (Backman and Sikora 2008;Saikkonen et al 2010). There are different beneficial effects of these endophytic fungi on host plants as plant growth promoting, increasing and induction of plant defense mechanisms, disease severity reduction, and producing of different anti-herbivore products (Yang et al 2016).…”