The Impact of Hydro-Priming and Osmo-Priming on Seedling Characteristics, Plant Hormone Concentrations, Activity of Selected Hydrolytic Enzymes, and Cell Wall and Phytate Hydrolysis in Sprouted Wheat (Triticum aestivum L.)

[Image: see text] Priming improves the seed germination rate and grain yield. Before this work was executed, little, if any, research has been reported on priming wheat for improving its nutritional properties. The impact of hydro-priming and osmo-priming using solutions with different water potentials on selected hydrolytic enzyme activities and their breakdown of starch, cell wall materials, and phytates during subsequent sprouting was studied here. A higher germination rate in the early growth stage of seedlings was found for hydro-primed or osmo-primed (−0.3, −0.6 MPa) grains. Hydro-primed sprouted grains had the longest radicles and coleoptiles and the highest hydrolytic enzyme activities. The latter lead to a 90% increase in reducing sugar, a 20% increase in water-extractable arabinoxylan, and an 8% decrease in phytate contents after 5 days of sprouting. This study thus offers opportunities for optimizing agricultural practice. The presence of different plant hormones and their concentrations are generally not affected by priming. However, the plant hormone concentrations in grains primed at −1.2 MPa and subsequently sprouted were lower than those in all other samples under study. The induction of too high osmotic stresses in these grains leads to disruption of the sprouting processes. Finally, it was for the first time found, based on the known biosynthesis pathways of wheat, that gibberellic acid (GA)20-oxidase in (primed) sprouted wheat is more active than GA3-oxidase and much more active than GA13-oxidase.