Dhia Bouktila - Higher Institute of Biotechnology of Béja. University of Jendouba, Tunisia
Saïda Kharrat - Faculty of Sciences of Bizerte. University of Cartago. Tunisia
Maha Mezghani-Khemakhem - Research Unit on Genomics of Crop Insect Pests (GIRC), Faculty of Sciences of Tunis, University of Tunis-El-Manar, Tunisia
Abderrahmane Jerraya - Department of Entomology, National Institute of Agronomy, Tunis, Tunisia
Mohamed Makni - Research Unit on Genomics of Crop Insect Pests (GIRC), Faculty of Sciences of Tunis, University of Tunis-El-Manar, Tunisia

The citrus leafminer, Phyllocnistis citrella Stainton (Lepidoptera: Gracillariidae) is a major invasive pest of citrus in Tunisia. In order to help the implementation of an efficient integrated management strategy, it was essential to assess the genetic diversity and population structure of the pest. For this purpose, random-amplified polymorphic DNA-polymerase chain reaction (RAPD-PCR) was applied, using eight oligo-nucleotide primers, to reveal genetic variability among eight populations of P. citrella, originating from the north, center and south of Tunisia. A total of ۶۶ RAPD markers and ۳۳ phenotypes were generated. Inter-population polymorphism was revealed, using the percentage of polymorphic markers (۶۲.۱۲ %), mean number of phenotypes generated per primer (۴.۱۲۵) and mean genetic distance (۰.۱۹۹). Hierarchical analysis, using the UPGMA method, indicated that the genetic variability was influenced by the regional distribution. This pattern of population clustering was supported by Principal Coordinate Analysis (PCO). Yet, a weak correlation (۰.۶۹) was revealed between genetic and geographic distances, suggesting that climatic contrariety between the north and south of Tunisia plays a major role in the differentiation of P. citrella, leading to a restriction of gene flow between populations. Results obtained in this work show clear genetic differences, which should be considered in the development of control strategies.

Citrus, Genetic diversity, Pest management, Phyllocnistis citrella, RAPD-PCR