Estimation of genetic parameters for yield traits in globe artichoke (Cynara scolymus L.)

Ten yield and phenological traits were evaluated in a population of 23 globe artichoke (Cynara scolymus L.) clones in order to estimate broad sense heritability, genetic coefficient of variation, expected selection gain and genetic correlations. The variation among clones was highly significant (p < 0.01) for all the characters, while the clone x year interaction was highly significant (p < 0.01) for days to first harvest (DH), harvest period (HP) and bottom height (BH). The interaction was also significant (p < 0.05) for the number of artichokes harvested (AN), height/diameter ratio (MR) and bottom diameter (BD). Heritability was intermediate to high: 0.83, 0.82, 0.94, and 0.48 for yield (YD), AN, MR and HP, respectively. The expected selection advance was related to the magnitude of the genetic coefficient of variation, and was over 30% of the mean for weight of secondary artichokes, bottom weight, harvest period and yield. Characters with highest association with yield were the number of artichokes and weight of secondary artichokes, W2, (r(g) = 0.98 and 0.99, respectively). Harvest period and days to harvest were negatively correlated (r(g) = -0.92**). DH was positively correlated with YD, W2, W1 and BW; while the opposite was true for HP; indicating that high yielding clones with good head size should be searched for in late maturing materials. Among the bottom quality characters, the high correlation between BW and W1 (r(g) = 0.94) would enable the consideration of the latter as an indicator of good industrial quality.