TABLE 3

Relative abundance of bacterial and fungal genera which comprise known biocontrol agents against grapevine downy mildew

GenusaMean relative abundance (%) of genera ± SEb
UD-UNTUD-PENUD-AZ78SM1-UNTSM1-PENSM1-AZ78SM2-UNTSM2-PENSM2-AZ78
Erwinia10.4 ± 0.2ab5.5 ± 0.9ab7.8 ± 2.4ab0.5 ± 0.1ab1.0 ± 0.5ab0.3 ± 0.2b22.3 ± 6.2a4.6 ± 3.7a0.2 ± 0.2b
Bacillus0 ± 0c0 ± 0c0 ± 0c0.8 ± 0.4ab1.1 ± 0.5a2.5 ± 0.6a0 ± 0c0.1 ± 0c0 ± 0c
Pseudomonas5.6 ± 2a8.2 ± 1.0a13.0 ± 2.6a2.7 ± 1.2a4.5 ± 3.4a3.2 ± 1.0a31.9 ± 2.8a27.2 ± 2.5a5.9 ± 0.5a
Stenotrophomonas0.3 ± 0.3a0.2 ± 0.1a0.6 ± 0.3a1.2 ± 0.4a0.6 ± 0.1a1.0 ± 0.5a0 ± 0a0 ± 0a0 ± 0a
Aureobasidium0.1 ± 0a0.1 ± 0.1a0.2 ± 0.1a0.1 ± 0a0.1 ± 0.1a0.3 ± 0.2a0.2 ± 0.1a0 ± 0a0 ± 0a
Fusarium0 ± 0a0 ± 0a0 ± 0a0 ± 0a0 ± 0a0 ± 0a0 ± 0a0 ± 0a0 ± 0a
Alternaria0.3 ± 0.1a0 ± 0b0 ± 0b0 ± 0b0 ± 0b0 ± 0b0 ± 0b0 ± 0b0 ± 0b
  • a Genera comprising known biocontrol agents against grapevine downy mildew: i.e., Erwinia herbicola, Bacillus spp., Pseudomonas spp., Stenotrophomonas maltophilia (22), Aureobasidium pullulans (75), Fusarium proliferatum (76), and Alternaria alternata (77).

  • b The relative abundance (%) of genera with possible biocontrol properties was determined at 97% sequence similarity for bacteria on the leaves of untreated plants (UNT) or of plants treated with penconazole (PEN) or with Lysobacter capsici AZ78 (AZ78) in Udine (UD), San Michele all'Adige (SM1), and San Michele all'Adige protected from rain (SM2). The mean values and standard errors (SEs) of three replicates are presented for each sample. For each genus, different superscript letters indicate significant differences according to Tukey's test (α = 0.05).