Sanitary Selection of Virus-Tested Fig (Ficus carica) Cultivars in Tunisia

Abstract

Field surveys were carried out during autumn 2011 and spring 2012, in different fig orchards located at Rafraf, Takelsa, Mornag, Djebba, Sousse, and Sfax to select virus-free plants. A total of 202 trees representing 26 fig cultivars were prospected and sampled. Total nucleic acids were extracted from leaf veins and tested by RT-PCR for the presence of FMV,FLMaV-1, FLMaV-2, FMMaV, FCV, and FFkaV using specific primers. PCR results indicate that all these viruses were present in the Tunisian fig orchards. The average of infection level determined by RT-PCR was 63.86%. FMV was proved to be the most widespread virus (37.12%), followed by FLMaV-1 (11.9%), FFkaV (11.4%), FCV (8.9%), FMMaV (8.4%), and finally FLMaV-2 (5.9%). Among the 26 tested cultivars, only 7 (Marghrebi, Boukhobza, Zagfar, Assafri, Kahli, Chetoui, Delgane) were free from the tested viruses. By the contrary, the sanitary status of the main Tunisian cultivars Bayoudhi, Bouhouli, Soltani, Zidi and Bither, seemed heavily degraded (75, 70.37, 69.23, 66.03, and 46.15% of infection, respectively). Seven cultivars (Wahchi, Khartoumi, Thguegli, Besbessi, Bidh-Bghal, Njeli and Khedhri) were totally infected. This study allowed the identification of at least one “virus-tested” candidate clone from 19 different fig cultivars which can represent the potential mother plants for propagating materials in order to establish new fig nurseries and orchards.

Keywords

• Fig
• RT-PCR
• sanitary selection
• Tunisia
• viruses