ABSTRACT: In this work, barley seed coating with urease and phosphatase, free and immobilized in humic acids, was studied as a tool to enhance the use efficiency of N and P by plants. The seeds were encapsulated in gels of Ca-alginate by a method that allows gelation of the polymer, containing enzymes, from the surface of seeds outward. The coating process did not affect seed germination. A pot experiment with the coated seeds was carried out. The seed coating with free enzymes increased soil ammonium-N (NH4+-N) and inorganic P up to 39 and 54 %, respectively, and up to 62 and 64 %, with the immobilized enzymes, in comparison with control pots. Seed coating improved N (47-137 %) and P (29-61 %) uptake by plants. Moreover, a synergistic response in N and P... |