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 isolategeneticvariantswithimprovedcellulasessecretion.Forthis purpose, we induced genetic recombination by bringing together thegenomesofP.echinulatumandTrichodermaharzianumthrough protoplastfusion.TheT.harzianumstrainwasisolatedasanintestinalsymbiontoftheColeopteraPassalusbinominatuserosusandalso secretescellulases,appearingatafastergrowththanP.echinulatum, but with a smaller production of it (data not shown).