Nevertheless, it has been difficult to obtain new cellulase mutants of P. echinulatum 9A02, although a good methodology has been applied [15]. Due to this, in the present work, we aimed to isolate genetic variants with improved cellulases secretion. For this purpose, we induced genetic recombination by bringing together the genomes of P.echinulatum and Trichoderma harzianum through protoplast fusion. The T.harzianum strain was isolated as an intestinal symbiont of the Coleoptera Passalus binominatus erosus and also secretes cellulases, appearing at a faster growth than P.echinulatum, but with a smaller production of it (data not shown).