Four glycosidases were analyzed in 10 mm apical segments prepared from growing roots (15 mm) of Zea mays L. The pH optima were found to be 5.8 for β-glucosidase, 4.4 for β-galactosidase, 6.4 for α-glucosidase and 6.0 for α-galactosidase. The β-glucosidase showed 4-fold higher activity than the