Detecció genètica mitjançant PCR a temps real de la presència de l’espècie invasora musclo zebrat (Dreissena polymorpha)

Abstract

Zebra mussel (Dreissena polymorpha, Pallas, 1771) is a bivalve mollusc species native from the Caspian and Black seas region. Since XIX century has expanded to central Europe, and it established in the Iberian Peninsula in 2001. The presence of D. polymorpha causes ecological impacts, affecting biodiversity, and economic impacts, blocking water-conductor infrastructures. In order to control and manage the infestation, different control and management plans have been established. Some of these organizations are Agencia Catalana de l’Aigua (ACA), Confederacion Hidrogràfica de l’Ebre (CHE), and Agencia Basca de l’Aigua (URA). These monitoring plans are carried out by observing larvae through a microscope, a technique with low specificity and sensitivity that can generate false positives. For this reason the molecular methods can be an alternative more reliable that could fix the problems like un-specificity and low sensitivity. Using gene histone H2B and Real-Time PCR, it is expected to be optimized a method to determine the infestation grade from environmental filtered-water samples. For do this, it’s necessary to optimize the previous steps, like DNA isolation and PCR amplification. The samples used in this project belong to different locations from Catalonia sampled in two seasons. Results obtained show that D. polymorpha DNA is present in all analysed locations. ACA has only confirmed the presence in one of them (La Baells Reservoir), suggesting the better molecular techniques specificity and sensitivity than traditional visual methods. We also have seen that in winter there are more D. polymorpha DNA prevalence in the water column than in summer, according with the reproduction period. This molecular analysis can be used like routine tool into the D. polymorpha control and management plans. Because its quickness and its great D. polymorpha DNA detection, the prevention efforts could be focussed to the locations with risk of infestation