Mineral Ion Nutrition of Developing Barley Grains 1. Effect of Magnesium Deficiency on Ion Content of Immature Embryos and Endosperms

The effect on the mineral ion nutrition of developing barleyembryos and endosperms was studied when both Mg and Mn werewithdrawn simultancously from the rooting medium. Both embryosand endosperms had lower Mg levels, on average 40 and 50 percent, respectively, over the developmental period, than thosefrom control plants grown in complete nutrient solution. Comparedto the controls, higher levels of Mn (average 20 per cent) andCa (average 20 per cent) were found in Mg-deficient embryosfrom test plants, but Mn levels were lower (average 30 per cent)and Ca levels unaffected in Mg-deficient endosperms. K levelsin both embryos and endosperms were not changed. The endospermsfrom test plants had lower total N levels than the controls. Hordeum vulgare L., barley, embryo, endosperm, sand culture, magnesium, manganese, calcium, potassium, nitrogen, mineral nutrition