Recent emergence and worldwide spread of the red tomato spider mite, Tetranychus evansi: genetic variation and multiple cryptic invasions

• DOI: 10.1007/s10530-010-9791-y
• Publication Date: 2010-06-03T10:20:27Z
• Authors: Angham Boubou; Alain Migeon; George K. Roderick; Maria Navajas
• Keywords: 0106 biological sciences; [SDV]Life Sciences [q-bio]; ravageur; 01 natural sciences; 630; INVASIONS CRYPTIQUES; zone méditerranéenne; EMERGING PEST; protection de l'environnement; SOLANACEES; MULTIPLE INTRODUCTIONS; CULTURE EMERGENTES; amérique du sud; Ecology, Evolution, Behavior and Systematics; 2. Zero hunger; microorganisme; Ecology; afrique; asie; légume; 15. Life on land; ESPECES INVASIVES; CRYPTIC INVASIONS; CRYPTIC INVASIONS; parasite; TETRANYCHUS EVANSI;MITOCHONDRIAL DNA;EMERGING PEST;MULTIPLE INTRODUCTIONS;CRYPTIC INVASIONS ;GENETIQUE DES POPULATIONS;CULTURE EMERGENTES;SOLANACEES;BIOSECURITE VEGETALE;ESPECES INVASIVES;INVASIONS CRYPTIQUES; varroa; MITOCHONDRIAL DNA; GENETIQUE DES POPULATIONS; europe; acarien; BIOSECURITE VEGETALE; TETRANYCHUS EVANSI

Plant biosecurity is increasingly challenged by emerging crop pests. The spider mite Tetranychus evansi has recently emerged as a new threat to solanaceous crops in Africa and the Mediterranean basin, with invasions characterized by a high reproductive output and an ability to withstand a wide range of temperatures. Mitochondrial (868 bp of COI) and nuclear (1,137 bp of ITS) loci were analyzed in T. evansi samples spanning the current geographical distribution to study the earliest stages of the invasive process. The two sets of markers separate the samples into two main clades that are only present together in South America and Southern Europe. The highest COI diversity was found in South America, consistent with the hypothesis of a South American origin of T. evansi. Among the invaded areas, the Mediterranean region displayed a high level of genetic diversity similar to that present in South America, that is likely the result of multiple colonization events. The invasions of Africa and Asia by T. evansi are characterized by a low genetic variation associated with distinct introductions. Genetic data demonstrate two different patterns of invasions: (1) populations in the Mediterranean basin that are a result of multiple cryptic introductions and (2) emerging invasions of Africa and Asia, each likely the result of propagules from one or limited sources. The recent invasions of T. evansi illustrate not only the importance of human activities in the spread of agricultural pests, but also the limits of international quarantine procedures, particularly for cryptic invasions.