Fig. 1

Primer design and testing. a Schematic representation of the annealing sites of forward and reverse GTAA, BITS, and SP primers in the fungal ribosal ITS. Reported amplicon sizes were calculated based on the ITS sequence of Eutypa lata (KU320617.1) as an example. b Bioanalyzer electropherograms showing PCR amplicons sizes generated using GTAA primers from purified fungal grapevine trunk pathogens: E. lata, Phaeoa. minimum, Dip. seriata, N. parvum, Phaeom. chlamydospora, and Dia. ampelina. Agrobacterium tumefaciens, V. vinifera and nuclease-free water were included as controls. c Bioanalyzer electropherograms showing PCR amplicons sizes generated using GTAA primers from selected field samples of mature vines infected with different trunk disease symptoms. AH: apparently healthy, ED: Eutypa Dieback, ES: Esca,WC: wood cankers (no leaf symptoms), and numbering corresponds to different biological replicates (same samples as in Fig. 5). d PCR products of GTAA, BITS, and SP primers from grapevine samples inoculated with N. parvum at six weeks post-inoculation sampled every five-cycles and visualized on an agarose gels. L: 100 bp Ladder. e Cycle thresholds (Ct) measured by qPCR of the same samples shown in (d)