ABSTRACT
In this work was to evaluate the conidiospores production of Trichoderma harzianum using barley straw as substrate. Four growth conditions were used; washed and unwashed barley straw and washed and unwashed barley straw supplemented with mineral salts. The highest spore production was observed when washed barley straw supplemented with mineral salts with 1.56â¯×â¯1010 conidiospores/gram of dry matter (gdm) at 216â¯h of cultivation was used. The effect of substrate moisture on spore production was studied, three initial moisture levels of the substrate were tested and it was observed that a humidity of 80 % of the substrate improves the production of conidiospores reaching a concentration of 2.35â¯×â¯1010 conidiospores/gdm at 136â¯h. Finally, conidiospores viability was evaluated for 12 months by keeping them on the conidia and substrate, and viability of 71 % of the conidiospores was observed, so this maintenance method is an excellent means of conserving the conidiospores viability.