Effects of the Annual Nitrogen Fertilization Rate on Vine Performance and Grape Quality for Winemaking: Insights from a Meta-Analysis

Table 3

Mean plus 95% confidence interval for the coefficients of the Mitscherlich law fitted to the vine production parameters and the yeast assimilable nitrogen, along with the N for 95% of each parameter (N_⟶95).

Normalized parameter	a	Na (g·vine^−1)	N ⟶95(g·vine^−1)
Grape yield	0.26 ± 0.15^a	5.5 ± 4.1^a	12 ± 7^a
Pruning weight	0.29 ± 0.24^ab	3.9 ± 3.5^a	12 ± 7^a
Bunch number	0.42 ± 0.61^ab	12 ± 16^ab	12 ± 16^ac
Bunch weight	0.11 ± 0.05^ab	17 ± 9^b	29 ± 12^bcd
Berry number	0.12 ± 0.10^ab	18 ± 42^ab	31 ± 53^ade
Berry weight	—	—	—
Yeast assimilable nitrogen	0.07 ± 0.02^b	25 ± 9^b	42 ± 14^be

For each curve coefficient, the means sharing at least one letter are nonsignificantly different at the 95% confidence level.