The effect of salicylic acid (SA) on the length of roots and shoots of Brosimum\nalicastrum seedlings was studied. Twelve-day-old seedlings developed in 20 cm\nlong PVC tubes filled with perlite were sprayed either with water or 1μM SA.\nWhen roots protruded from the base of the tube, the seedlings were harvested and\nmeasured. Results showed that SA treatment significantly increases the length of\nroots and shoots by 22 % and 21%, respectively, in comparison with those of the\ncontrol. These significant differences were also present in the fresh weight of the\nroots. This is the first report to show that SA affects the growth of seedlings trees\nfrom the Mexican tropics that produces recalcitrant seeds.