How Megaplatypus mutatus Behaves inside a Trunk? Studying its Galleries via Computerized Axial Tomography and Digital Images Processing

DOLINKO, ANDRES EZEQUIEL; COSTALES, YASMIL; CARMARAN, CECILIA; CERIANI NAKAMURAKARE, ESTEBAN

Congreso; 63rd Society of Wood Science & Technology. Portoro?-Slovenia; 2020

Megaplatypus mutatus (syn. Platypus sulcatus), an ambrosia beetle native toSouth America, is one of the main forest pests in Argentina and an emergentforeign pest in Europe, representing a potential risk to forest and fruitplantations due to its low specificity. Special attention has been given topoplar plantations as a result of the high economic impact. This ambrosiabeetle attacks vigorous hosts producing multiple attacks per tree, triggering astructural weakening and eventually causes the breakdown of the tree trunk;especially when weather conditions are unfavourable. Even though therelevance of understanding the microhabitat where this complex systemdevelops, this is the first comprehensive study that characterizes the galleriesof this forest pest analyzing the topology of tunnels, the implications in thewood structure and the reproduction of M. mutatus. In this context, twocommercial plantations were sampled where we studied 28 attacked treeswith a Philips-MX16-slice tomographer, generating ≈ 5200 slides. A specialcomputer algorithm that allows isolating the galleries from the rest of theimage was specially developed. This allowed characterizing with highprecision the geometry, dimensions and topological properties of the galleriesin all the samples, as well as, a 3D visualization of the structure. The impactsof the obtained results in the frame of the pathogenic system are discussed.