Fig. 2. Single-plant yield frequency distribution of the source material (a), and of the first generation H (continues line) and L (dotted line) families in Site 1 (b) and Site 2 (c), under the ultra-low density (ULD) of 1.2 plants/m². ( = mean yield, CV = coefficient of variation, Sk. = skewness, Kur. = kurtosis, n = number of harvested plants). P < 0.05, P < 0.01, P < 0.001.