Malathion bait sprays to control medfly, Ceratitis capitata (Diptera: Tephritidae), in Tunisian citrus orchards is expected to be phased out in the near future due to low residue tolerance in the fruits by consumers. Attract and kill strategy that encompasses mass trapping and bait station techniques has become a widespread method for controlling medfly. Effectiveness of two bait station methods (AAL&K® and Ceranock®) and two attractants for mass trapping (Ceratrap® and Starce®) was, respectively, compared with malathion and spinosad in Grombalia and Chott-Mariem experimental sites. Ceranock® and AAL&K® provide effective protection of citrus fruits from medfly attack as confirmed by low rate of damaged fruits of respectively 3.88 and 2.26% compared with malathion (21.63%). Medfly population and rate of fruit damage were significantly lower in Ceratrap® than in Starce® and spinosad treated plots. Rate of fruit damage on Starce® treated plots increased at least three times more than in Ceratrap®, and one-and-half times more than in spinosad treated plots. Ceranock® and AAL&K® bait station devices are a cost-effective alternative to the use of insecticides in citrus orchards and can be used in IPM schemes against medfly in association with other environmentally friendly approaches.

Phenacoccus solenopsis Tinsley (Hemiptera: Coccomorpha: Pseudococcidae), the cotton mealybug, is an invasive polyphagous species that has been extending its geographic range, posing a conspicuous threat to many Mediterranean crops of economic importance. These include three species of Solanaceae, namely Solanum lycopersicum L. (tomato), Solanum tuberosum L. (potato) and Solanum melongena L. (eggplant) all of which are economically important worldwide. In this study, we used age-stage two-sex life tables to investigate the suitability of these three plant species as hosts for P. solenopsis and to calculate pest fitness, life history parameters and population projection parameters. All tested host plants that were suitable for the pest and eggplant host plant induced a higher fecundity (276.50 ± 10.78 eggs/female), net reproductive rate (R₀) (243.32 ± 15.83 offspring/female) and finite rate of increase (λ) (1.18 ± 0.0043 day⁻¹) and more extended adult longevity (males: 6.50 ± 0.34 days and females: 24.15 ± 0.50 days). Population growth predictions over a period of 90 days of infestation, commencing with an initial population of 10 eggs showed that adult population size was 674,551 on tomato, 826,717 on potato and 355,139 on eggplant. Our data on plant host preference of P. solenopsis will aid the development of appropriate management strategies and achieve successful control of this invasive pest in key Mediterranean crop systems.

A new vegetative disorder was observed in Tunisian carrot (Daucus carota subsp. sativus) fields consisting of leaf curling, a yellowish purply-bronze discolouration of the leaves, as well as a stunted carrot shoots with an abundance of secondary roots. The causal agent was recently proven to be a bacterium ’Candidatus Liberibacter solanacearum’ (Lso) which infects plants and seeds. Subsequently, using multiple sampling techniques, a wide-scale survey was carried out in all the symptomatic areas in order to identify the insects potentially capable of vectoring the bacterium. This revealed in all the symptomatic carrot fields two psyllid species, Bactericera trigonica and B. nigricornis (Förster, 1848), never before reported in Tunisia and shown in the literature to be vectors of Lso. In addition to carrot, surveys across Tunisia found these psyllid species on other host plants belonging to the Apiaceae family, such as wild fennel, celery and parsley, and confirmed the diversity of their host range and their potential to develop on many wild and cultivated plants. The possible phytosanitary risks which derive from the presence of these two insects on carrot and associated crops are discussed as well as their potential role as vectors of Lso.