Harvest time and yield of globe artichoke in relation to the environment of transplants production

The positive influence of low temperatures during the vegetative phase on bolting time of globe artichoke has been demonstrated. The aim of this work, conducted in Sicily (south Italy), was to compare the growth and yield responses of plantlets of clone '9/8' of 'Violetto di Sicilia' produced on the coastal plain (Siracusa, 15 m above sea level) and on the mountain (S. Domenica Vittoria - Messina, 1100 m above sea level). The comparison of the two plantlet lots was made at Siracusa (as before) and Moio Alcantara - Messina (560 m above sea level) by two growing seasons in order to ascertain the better environment for developing nursery activity for globe artichoke. The plantlets produced on the mountain benefited by cold temperatures in contrast to those produced on the coastal plain. As a consequence of this, crops from the plantlets produced on the mountain, in comparison to those from plantlets produced on the coastal plain, showed a higher leaf emergence rate, earliness in the start of head harvest, faster head yield rate and consequently greater total yield cumulated at the end of cycle and a lower number of leaves at bolting stage. These results indicate that it could be very useful to develop nurseries for producing artichoke plantlets in the mountain areas