1. Research and Development Department, Nutrafur-Furfural Español S.A., Camino Viejo de Pliego s/n, 80320 Alcantarilla, Murcia, Spain; Plant Biology Department, Faculty of Biology, University of Murcia, 30100 Espinardo, Murcia, Spain; and SAIT, Polytechnic University of Cartagena, 30203 Cartagena, Murcia, Spain