TABLE 2

Correlations among bacterial and fungal OTU identified on grapevine leaves with environmental conditions and functional properties against downy mildewa

Leaf community and phylumCorrelation of relative abundance with indicated environmental parameterCorrelation of relative abundance with downy mildew severity
TmaxTminTavgRainfall
Bacteria
    Betaproteobacteria–0.090.09–0.09–0.900.70
    Alphaproteobacteria0.09–0.090.090.90–0.50
    Actinobacteria–0.180.18–0.180.84–0.18
    Gammaproteobacteria–0.270.27–0.27–0.790.37
    Firmicutes0.000.000.000.74–0.30
    Archaea0.37–0.370.370.74–0.55
    Deinococcus-Thermus0.000.000.000.63–0.18
    Bacteroidetes0.000.000.000.84–0.67
    Acidobacteria0.41–0.410.410.72–0.79
    Deltaproteobacteria–0.250.25–0.250.290.07
Fungi
    Ascomycota0.82–0.820.820.47–0.73
    Basidiomycota–0.820.82–0.82–0.470.75
    Fungi–0.370.37–0.37–0.740.82
    Glomeromycota0.65–0.650.650.59–0.73
    Zygomycota0.82–0.820.820.05–0.75
  • a Spearman's rank correlation coefficients are based on the relative abundances of bacterial and fungal OTU identified on grapevine leaves and the effect of microbial communities against downy mildew (Fig. 6) and the environmental parameters of maximum temperature (Tmax), minimum temperature (Tmin), mean temperature (Tavg), and rainfall (mm). Significant (P < 0.01) correlations are indicated in boldface. Maximum temperatures (Tmax): 28.5°C at Udine (UD), 31.5°C at San Michele (SM1), and 31.5°C at San Michele protected from rain (SM2). Minimum temperatures (Tmin): 12.1°C at UD, 9.7°C at SM1, and 9.7°C at SM2. Mean temperatures (Tavg): 20.0°C at UD, 21.1°C at SM1, and 21.1°C at SM2. Rainfall: 49.2 mm at UD, 56.6 mm at SM1, and 0 mm at SM2.