Breeding for high magnesium (Mg) concentrations pas been conducted
for several forage species. Mgwell, Magnet, and HiMag are the first
experimental strains, bred for increased Mg concentrations of orchardgrass,
Italian ryegrass, and tall fescue, respectively. This experiment
compared the performance and genetic variability of these high-Mg
cultivars grown in solution culture with other cultivars in each species.
Three mineral absorption experiments were carried, out with one month
aged seedlings. Seedlings were evaluated for shoot dry weight, uptake and
concentration of Mg, calcium (Ca), and potassium (K), and also the
density of these minerals in the shoot. The cultivars of different species
behaved differently among the experiments even though the over all
environmental condition was kept similar. The high-Mg cultivars showed
higher Mg uptake per plant, but the differences were not so distinct.
However, the trend in Mg concentration among the cultivars of different
species was similar, and the difference between high-Mg cultivars and
control cultivars was distinct. The Mg density in the shoot of these
cultivars was significantly high. Also the high-Mg cultivars showed lower
equivalent ratio, K/(Ca+Mg). Genotypic differences in high-Mg cultivars
with others could be distinctly explained by differences in Mg
concentration and Mg density in the shoot, which coupled with low
K/(Ca + Mg) ratio. These common properties of high-Mg cultivars might
be considered as a good parameter for screening