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Cetaceans are large mammals widely distributed on Earth. The fin whale, Balaenoptera physalus, is the second largest living animal. In the 20th century, commercial whaling reduced its global population by 70%, and in the Mediterranean Sea not only was their overall population depleted but the migration between the Mediterranean Sea and the Atlantic Ocean was reduced. Previous genetic studies identified isolation between these two regions, with a limited gene-flow between these adjacent populations based on nuclear and mitochondrial markers. However, only limited information exists for the Mediterranean population as genetic diversity and abundance trends are still unknown. In this study, 39 highly polymorphic microsatellite markers were tested, including 25 markers developed de novo together with 14 markers previously published. An average allelic diversity of 8.3 alleles per locus was reported, ranging from 3 to 15 alleles per locus, for B. physalus. Expected heterozygosity was variable among loci and ranged from 0.34 to 0.91. Only two markers in the new set were significantly deviant from the Hardy Weinberg equilibrium. Cross-species amplification was tested in four other cetacean species. A total of 27 markers were successfully amplified in the four species (Balaenoptera acutorostrata, Megaptera novaeangliae, Physeter macrocephalus and Globicephala melas). A multivariate analysis on the multilocus genotypes successfully discriminated the five species. This new set of microsatellite markers will not only provide a useful tool to identify and understand the genetic diversity and the evolution of the B. physalus population, but it will also be relevant for other cetacean species, and will allow further parentage analyses. Eventually, this new set of microsatellite markers will provide critical data that will shed light on important biological data within a conservation perspective.

Nesidiocoris tenuis (Reuter) (Hemiptera : miridae) is a zoophytophagous bug used as a biological control agent in most of the countries. However, in Provence-Alpes-Côte d’Azur (France), N. tenuis is considered as a pest in so its damages on crops have some important economic impacts in the tomato greenhouses. This study aims to understand the effects of some environmental and cultural factors on the bug populations. To achieve this goal we have followed N. tenuis population in 14 greenhouses which used different strategies to fight against the bug during 4 months. It has been shown that the nets placed on the greenhouse windows greatly limit the bug entering. Only 4 of the 9 net-equipped greenhouses have been attacked by the bug whereas 8 out of the 9 non-net-equipped greenhouses have been touched. The use of the vacuum from the very first bug observation can slow down its development until 1 month. At the variety level, Marnero variety and the vigorous plants show a better tolerance to the bug plant feeding. Marnero shows 33% less damages than the most sensitive variety identified. In general, the very vigorous plants (stem diameter > 2 cm) show 21% less damages than the weak plants (stem diameter < 1,6 cm). In case of strong colonization of the greenhouses the yellow sticky traps with dry glue are very effective to control the adult flying bugs. An example of control strategy has been developed, this aims to prevent the entering of the bug in the greenhouse and, if the bug is already inside, provides some control technics and advice. This includes the new Koppert biocontrol product Capsanem which control a mean of 62% of a larval population in 2 weeks. The results of this exploratory study can’t be taken as scientific truth. All the highlighted control methods should be tested in controlled conditions.; Nesisidocoris tenuis (Reuter) (Hemiptera : miridae) est une punaise zoophytophage utilisée comme auxiliaire de culture dans la majeure partie du monde. Cependant, dans la région Provence-Alpes-Côte d’Azur (France), l’activité phytophage de N. tenuis provoque des dégâts et des pertes économiques considérables dans les serres de tomates. Cette étude exploratoire vise à connaître l’impact de facteurs environnementaux et culturaux sur les populations de N. tenuis dans les serres de culture hors-sol de tomate. Pour cela, les populations de N. tenuis ont été suivies durant 4 mois dans 14 serres réparties dans la région. Il a pu être démontré que la présence de filets sur les ouvrants des serres est un frein considérable à l’installation de la punaise. La lutte par aspiration, dès l’émergence de N. tenuis dans la serre, a pu ralentir le développement de la punaise pendant un mois. La variété Marnero et les plantes à forte vigueur ont été identifiées comme potentiellement tolérantes à la punaise. Les panneaux englués jaunes à glue sèche ont montrés une forte efficacité pour le contrôle de N. tenuis. Une stratégie de contrôle, abordant à la fois la prévention du risque et la gestion de la punaise, a été imaginée. De par la nature exploratoire de l’étude il sera important de réaliser des expérimentations en conditions contrôlées pour vérifier toutes ces observations.