Figures (6)  Tables (2)
    • Figure 1. 

      Summary effect sizes (ln ratio of the response in UGT overexpressing plants/ WT plants; ln R). Horizontal bars associated with summary effects represent the 95% confidence intervals. n is the number of studies contributing to each summary effect. p-values ≤ 0.05 were taken as significant.

    • Figure 2. 

      The effect sizes of UGT overexpression on root length under different experimental conditions of abiotic stress. The horizontal error bars represent the 95% confidence interval. .

    • Figure 3. 

      The effect sizes of UGT overexpression on germination rate under different experimental conditions of abiotic stress. The horizontal error bars represent the 95% confidence interval.

    • Figure 4. 

      The effect sizes of UGT overexpression on survival rate under different experimental conditions of abiotic stress. The horizontal error bars represent the 95% confidence interval..

    • Figure 5. 

      The effect sizes of UGT overexpression on relative anthocyanin contents under different experimental conditions of abiotic stress. The horizontal error bars represent the 95% confidence interval.

    • Figure 6. 

      The effect sizes of UGT overexpression on electrolyte leakage under different experimental conditions of abiotic stress. The horizontal error bars represent the 95% confidence interval.

    • Indicator effect sizeSummary EeffectaFunnelbKendallcEgger'sdDuval & Tweediee
      NLnRpplottaupβpAdjusted#trim
      Relative anthocyanin contents330.4870.001YES0.390.00−2.590.000.4875
      Root length800.2690NO0.020.770.640.00−0.07231
      Germination rate1810.1580NO0.120.03−0.030.960.1840
      Survival rate1510.5350NO0.040.490.460.000.25537
      Flavonols content110.3530.151YES−0.150.59−299.130.430.3361
      Water content40.4080.791NO−0.600.50−320.030.220.1080
      Water loss480.0140.9NO−0.380.00−6.710.000.0140
      Stomatal aperture110.4350YES−0.360.14−0.620.010.4360
      completely closed Stomatal40.2800.492YES−0.500.31−1277.390.050.2800
      Partially closed Stomatal40.2290.575YES−0.500.50−1851.040.040.2290
      completely open Stomatal40.4080.467NO−0.171.00−513.780.60−0.3921
      Electrolyte leakage78−0.310.001NO−0.010.87−274.240.55−0.41318
      chlorophyll content120.1640.488NO−0.140.58−382.070.140.1640
      Proline content140.250.253NO−0.011.00−151.850.790.2500
      Soluble sugar contents120.0970.682NO−0.170.49−707.590.030.0970
      a Summary effect: N = number of studies, ln R = natural log of the overall summary effect, p = probability that the summary effect ≠ 0; b Funnel plot appears asymmetrical; c Begg and Mazumdar Kendall rank correlation: tau = rank correlation coefficient (with continuity correction), two-tailed p = probability that the study effect sizes are correlated with their sampling variances; d Egger's linear regression: β = intercept of the regression line, p = probability of significant asymmetry in the study effect size/study size association. The regression runs through zero if the funnel plot is symmetrical. The size of the deviation of the intercept from the origin is a measure of asymmetry, with a two-tailed p < 0.05 indicating significant asymmetry. e Duval and Tweedie trim and fill: adjusted summary effect after imputing missing studies using an iterative trim and fill procedure, #trim = number of studies imputed in the trim and fill exercise.

      Table 1. 

      Measures used in characterizing publication bias for each effect size.

    • CategoryQtaPheterobI2cChange (%)
      Relative anthocyanin contents (S)2.071073
      Root length (S)112.47045.76344
      Germination rate (S)2303.961093.74723
      Survival rate (S)190.658038.109115
      Flavonols content (S)0.4711044
      Water content (S)0.070.995050
      Water loss (S)11.917102
      Stomatal aperture (width/length) (S)2.7430.949056
      Completely closed stomatal (%) (S)0.30.584073
      Partially closed stomatal (%) (S)1.3890.23927.98249
      Completely open stomatal (%) (S)0.4980.480−37
      Electrolyte leakage (%) (S)4.73110−33
      Chlorophyll content (S)0.2911021
      Proline content (ug·g−1·FW) (S)0.3651062
      Soluble sugar contents (ug·g−1·FW) (S)0.1261030
      Relative anthocyanin contents (N)0.6620.995028
      Root length (N)0.9610−1
      Germination rate (N)58.8210.00542.197−4
      Survival rate (N)0100
      Flavonols content (N)0.1610.923037
      Water content (N)0
      Water loss (N)0100
      Stomatal aperture (width/length) (N)00.9940−3
      Completely closed stomatal (N)0.0170.89701
      Partially closed stomatal (N)0.020.88706
      Completely open stomatal (N)0.0390.8440−12
      Electrolyte leakage (N)0.684104
      Chlorophyll content (N)0.0030.95702
      Proline content (N)0.08810−6
      Soluble sugar contents (N)0.06210−7
      a Qt, total observed variation among studies; b phetro, probability that Qt was due entirely to sampling error and not to real variation among studies; c I2, percentage of heterogeneity due to variation among true effects. Positive values indicating UGT overexpression promotion and negative values indicating UGT overexpression inhibition. (S) represents the heterogeneity of stressed plant; (N) represents the heterogeneity of non-stressed plant.

      Table 2. 

      Heterogeneity statistics for the 30 summary effect sizes under overexpressing UGT genes.