Verticillium Wilt of Artichoke (Cynara cardunculus subsp scolymus L.): Current Situation in Tunisia

In Tunisia, globe artichoke is grown in 2400 ha and it constitutes an important crop especially in the Low Valley of Medjerda. However, in the last years, harvested area, production and yield have been declining. This is mostly due to viral diseases in most cases. A first report run in 2006 demonstrated the presence of Verticillium in globe artichoke crops in a coastal region (Chott-Mariem). Since then no other works were done to estimate the situation of this fungal disease in Tunisia. The aim of this study is to confirm the existence of this soil borne fungus and to locate infested regions in Tunisia. Twenty three commercial globe artichoke fields were selected for inspection. Eleven of them are in the main production areas located in the Low Valley of Medjerda (4 fields in Jedayda, 3 in Utique and 4 in Medjez el Bab), and the other 12 fields are in new regions of culture of artichoke (2 fields in Tazarka, 2 in Foukaiya, 4 in Chott-Mariem, 1 in Bouficha, 2 in Zaghouan and 1 in Matmata). Verticillium wilt was found in 41% of sampled fields. The 55.5% of infected fields, were 3 or 4 years old, 33.3% were 2 years old and only 11.2% were one year old. The cultivar 'Violet d'Hyeres' which is the most cultivated in Tunisia, is the most sensitive to verticillium wilt. The 57% of prospected fields are situated in the Low Valley of Medjerda where farmers practice the rotation of globe artichoke with tomato which is also a host of this fungal disease; moreover they use plant material propagated in their own contaminated fields.