Effect of Propagation Methods and Sowing Dates on Aphid Infestation and Flower Heads Characters in Globe Artichoke Plants

The present study aimed to evaluate the effect of three methods of propagation of globe artichoke; crown pieces, off-shoots & ovoli and three planting dates on aphid infestation, mainly (Aphis fabae L, A. gossypii Glov., Macrosiphum euphorbiae T., M. solani (Kalt.), and Myzus persicae (Sulzer) in the field in relation with flower head characters. Planting was carried out on July 20, 10 and 31 of August during 2014/2015 and 2015/2016 seasons as early, ordinary and late dates of sowing, using the abovementioned three methods, at Shubramunt Village, Giza. Results showed significant differences among the weekly mean numbers of aphid as affected by the three tested methods of planting at the three tested sowing dates. Aphid infestations were generally low or moderate on G. artichoke when using the crown pieces comparing with the other two tested methods in both seasons under the three tested sowing dates. The lowest infestation observed with the normal date, especially by using crown pieces. As for flower head characters, results showed that neither propagation methods nor dates of sowing had significant effect on the average diameter or length of the formed head in both seasons. Also, using crown pieces gave significant increase in number and weight in flower heads compared to the other two tested methods. The greatest number of heads/ plant associated with the early date of planting, while its greatest weight correlated with the normal planting date under the three tested methods of propagation during the two studied seasons.