The green peach aphid Myzus persicae Sulzer (Hemiptera, Aphididae) is an important pest of pepper, Capsicum annum (Solanaceae), with infestations by this aphid resulting in serious economic damage. Commonly, biological parameters are used to compare insect fitness on different varieties of pepper. Effect of rearing M. persicae on nine varieties of pepper (Anamex, Balconi, Bami, Chargui, Garn ghzel, Italico, J27, Starter and Torero) on the population density and percentage infestation it achieves, and its mean relative growth rate (MRGR) and generation time were studied under laboratory conditions. The highest population density, maximum percentage infestation (92.93%), minimum generation time (10.95 days) and highest MRGR (0.063) were recorded on the variety Chergui and the lowest population density, minimum percentage infestation (51.4%), minimum MRGR (0.043) and maximum generation time on the variety Anamex. For this, we need to know the behaviour of this aphid on different cultivated varieties of pepper in Tunisia and the susceptibility or resistance of these varieties to this aphid. This is a fundamental component of an integrated pest management program for any crop.In the present paper, the biological parameters of M. persicae reared under controlled conditions were studied in order to describe this aphid's behaviour on nine varieties of pepper. Materials and Methods Biological MaterialAphids were collected from a parthenogenetic population on pepper in a field at Chott Mariem in Tunisia (36°48ʹN, 10°11ʹE) and reared for several generations on sweet pepper in a green house at 21 ± 2 °C, HR: 60-80% and under a long day photoperiod (L:D 14:10) (Troncoso et al. 2005). These aphids were needed to infest the pepper plants used in the experiments.Nine varieties of Capsicum annum L. pepper (Anamex, Balconi, Bami, Chargui, Garn ghzel, Italico, J27, Starter and Torero) were used as host plants, which were established from seed sown in 12 cm diameter plastic pots filled with suitable soil. At the 8th leaf stage, plants were infested with M. persicae.

In August 2013, Phenacoccus madeirensis Green, (Hemiptera: Pseudococcidae) was identified for the first time in Tunisia, in the region of Akouda (Sousse, coastal area of Tunisia) on Cestrum nocturnum (Solanaceae) during a survey. The infestation was observed on leaves, shoots and also on the collar. This is the first record of P. madeirensis in Tunisia and the first record of this pest in North Africa. Two other mealybugs Peliococcus cycliger and Planococcus citri were also recorded during this survey. They have previously been reported in Tunisia.

During the summer and autumn of 2014 the mealybugs Maconellicoccus hirsutus (Green, 1908) (Hemiptera: Pseudococcidae) and Phenacoccus peruvianus Granara de Willink, 2007 (Hemiptera: Pseudococcidae) were observed in different localities of Sousse (Tunisia). This is the first record for both of these species in Tunisia and in North Africa. For M. hirsutus, this was also the first record of the species in a Western Mediterranean country. It was observed on Hibiscus rosa‐sinensis (Malvacae). P. peruvianus was collected from Bougainvillea glabra (Nyctaginaceae) and Citharexylum quadrangularis (Verbenacae).

Pterochloroides persicae (Cholodkovsky) is an aphid species belonging to the subfamily Lachninae that uses different members of Rosaceae (specially Prunus spp.) as hosts. Partial sequences from the mitochondrial cytochrome c oxidase 1 (COI) and the nuclear long-wave opsin genes were obtained for approximately 100 P. persicae aphid individuals sampled from 34 colonies collected mainly in Tunisia and other Mediterranean locations. The variability found at the mitochondrial locus revealed the presence of two maternal haplotypes in the studied area that differed in a single nucleotide. The nuclear gene analyzed, however, failed to reveal any variability in this species. The variability found at the COI locus was related to the season of aphid sampling and with the site of feeding, with haplotype I mostly detected in samples collected in spring and summer on trunks and branches and haplotype II only detected in aphids collected in autumn on roots. The observed pattern of molecular variation suggests the presence of two clonal races of P. persicae coexisting in the studied area differentially adapted to conditions prevalent in the alternative seasons and/or to different feeding sites.

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