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An increase in international trades in goods and services and the movement of humans in recent decades has led to a concomitant increase in the number of exotic insects invading new areas, with some establishing as harmful agricultural pests. That is how the South American tomato pinworm, Tuta absoluta (Lepidoptera: Gelechiidae) has recently and rapidly invaded Niger except the Diffa region. This new pest represents a real threat for tomato production in the country. To this end, the first step includes identifying the fortuitous natural enemies present. For this purpose in Niger, five tomato-infested fields from three distant and climatically different agricultural regions were sampled, with a particular focus on predatory mirids. Based on morphological characters and molecular barcoding approach, Nesidiocoris tenuis, N. volucer and N. callani (Miridae: Dyciphini) were reported for the first time in Niger and associated with tomato pests providing new insights upon their distribution areas and ecology, and genetic diversity. These findings are discussed in the framework of T. absoluta management and also the need of accurately identifying the community of natural enemies when facing invasive species. [ABSTRACT FROM AUTHOR]

When a promising natural enemy of a key pest exists locally, it is a common practice in biological control (BC) to rear and release it for supplementary control in the targeted agroecosystem even though significant knowledge gaps concerning pre/post release may still exist. Incorporating genetic information into BC research fills some of these gaps. Habrobracon hebetor , a parasitoid of many economically important moths that infest stored and field crops worldwide is commonly used, particularly against the millet head miner (MHM), a key pest of millet in Sahelian countries. To advance our knowledge on how H. hebetor that occurs naturally in open-field cropping systems and grain stores as well as being mass-produced and released for MHM control, performs in millet agroecosystems in Niger we evaluated its population genetics using two mitochondrial and 21 microsatellite markers. The field samples were genetically more diverse and displayed heterozygote excess. Very few field samples had faced significant recent demographic bottlenecks. The mating system (i.e. nonrandom mating with complementary sex determination) of this species may be the major driver of these findings rather than bottlenecks caused by the small number of individuals released and the scarcity of hosts during the longlasting dry season in Niger. H. hebetor population structure was represented by several small patches and genetically distinct individuals. Gene flow occurred at local and regional scales through human-mediated and natural short-distance dispersal. These findings highlight the importance of the mating system in the genetic diversity and structure of H. hebetor populations, and contribute to our understanding of its reported efficacy against MHM in pearl millet fields. [ABSTRACT FROM AUTHOR]