A Carvalho1, H Guedes-Pinto, J Lima-Brito. 1. Institute for Biotechnology and Bioengineering (IBB), Centre of Genetics and Biotechnology (CGB) of University of Trás-os-Montes and Alto Douro (IBB/CGB-UTAD), P. O. Box 1013, 5001-801 Vila Real, Portugal. anacarvalho@mail.com