Primary Metabolites (Free Sugars, Amino, Organic and Fatty Acids) of Grape Berries as Influenced by Esca Complex Disease (Grapevine Leaf Stripe) Foliar Symptom Severity

Abstract

In this study, berry samples were collected from healthy (control) and symptomatic vines of the white varieties Viosinho and Malvasia-fina. Symptomatic vines showed two different degrees of severity at harvest, namely chlorotic and scorched leaves (severity level 1) and tiger stripe leaves (severity level 2). The total fatty acid content was reduced in both varieties and the total organic acid content was unchanged. The total free sugar content increased with symptom progression in Viosinho but remained unchanged in Malvasia-fina. Varietal differences were observed in the response of amino acids, whose levels increased in Malvasia-fina and decreased in Viosinho.

Keywords

• grapevine leaf stripe disease
• <i>Phaeomoniella chlamydospora</i>
• biosynthetic pathways
• disease resistance and tolerance
• <i>Fomitiporia mediterranea</i>
• primary metabolism