Method for enhancing chlorophyll concentration in plants

A method of increasing at least one of the chlorophyll-a concentration and the chlorophyll-b concentration in the leaves of a plant of the genus Hordeum which has been hydroponically grown from seed over a duration of from about 2 to about 4 weeks, the method comprising:

• germinating the seed at a temperature of from about 20 to about 40° C.;
• transferring the germinated seed into an aqueous hydroponic dispersion having a temperature of from about 20° C. to about 40° C., wherein the aqueous hydroponic dispersion comprises nanoparticles of magnesium aluminate (MgAl2O4) at a concentration of from about 20 to about 200 mg/L and further wherein MgAl2O4 has a cubic spinel structure, as determined by X-ray diffraction (XRD);
• for the duration of about 2 to about 4 weeks after the transferring, maintaining the aqueous hydroponic dispersion at a temperature of from 20 to about 40° C. and subjecting the aqueous hydroponic dispersion to dark period-to-light period cycling, wherein each dark period is of x hours, each light period is of (24-x) hours and x is from about 6 to about 12;
• and,
• for the duration of about 2 to about 4 weeks after the transferring, periodically adding nanoparticles of MgAl2O4 to the aqueous hydroponic dispersion to maintain the concentration of the nanoparticles in the aqueous hydroponic dispersion at from about 20 to about 200 mg/L, wherein the periodically added MgAl2O4 has a cubic spinel structure, as determined by X-ray diffraction (XRD).