Susceptibility to flavescence dorée of different Vitis vinifera genotypes from north‐western Italy. (1st November 2020)

• Record Type: Journal Article
• Authors: Ripamonti, Matteo; Pegoraro, Mattia; Morabito, Cristina; Gribaudo, Ivana; Schubert, Andrea; Bosco, Domenico; Marzachì, Cristina
• Is Part Of: Plant pathology. Volume 70:Number 3(2021)
• Page Start: 511
• Page End: 520
• Publication Date: 2020-11-01
• Subjects: flavescence dorée -- grapevine cultivar -- micropropagated Vitis -- Scaphoideus titanus -- susceptibility -- tolerance; Agricultural pests -- Periodicals; Plant diseases -- Periodicals; 632
• DOI: 10.1111/ppa.13301
• Languages: English
• ISSNs: 0032-0862

Abstract

Abstract: The aim of this work was to evaluate the susceptibility to flavescence dorée (FD) of 12 Vitis vinifera cultivars grown in Piedmont, and representative of the wine‐making tradition of this area. The experiments were conducted under controlled conditions to ensure constant infection pressure. Test plants were ex vitro potted vines, singly inoculated with four Scaphoideus titanus infected by FD‐C phytoplasma (FDp), under greenhouse conditions. Vines were tested for FDp at 5 and 8 weeks postinoculation (wpi) and the phytoplasma load was measured in leaves and roots at 8 wpi. Within the 14 V. vinifera accessions (belonging to 12 cultivars), three susceptibility clusters were identified. Cultivars within the low susceptibility group showed low phytoplasma loads and low percentages of infected plants, suggesting a tolerant behaviour. To confirm these results, four Vitis cultivars, representing extremes of FD susceptibility from low to high, were grafted onto Kober 5BB rootstocks and inoculated with laboratory‐infected S . titanus, under semi‐field conditions. The transmission experiments onto grafted cuttings confirmed that susceptibility to the disease depends on the scion genotype. The data indicated that none of the tested V . vinifera genotypes are resistant to FD, although some cultivars with low susceptibility are available, and can be explored for identifying genetic traits involved in disease tolerance/resistance. Moreover, ranking Vitis genotypes for their susceptibility to FD is in itself a valuable tool to support vine growers in their decision management, by helping them to choose the most appropriate varieties according to their specific FD epidemiological contexts. Abstract : Fourteen grapevine accessions of Piedmontese varieties were screened for susceptibility to flavescence dorée on inoculation with infective Scaphoideus titanus . High, medium, and low susceptibility clusters were identified.