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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

Asexual fungus Neotyphodium spp. are often associated with aboveground parts of different grasses. Perennial ryegrass (Lolium perenne L.), dominant cool-season grass species in New Zealand, is frequently infected by endophytic fungus (Neotyphodium lolli). To evaluate the growth, nutrient status, and avoidance to dehydration stress, clones of diploid perennial ryegrass either infected with Neotyphodium lolii AR29 endophyte (E+) or not infected (E−) were grown in a potted Andisol with intermittent wetting-drying cycles in a controlled growth chamber. Results showed that endophyte infection (E+) significantly reduced plant height, tiller number, shoot and root dry weights, and root volume with an associated increase in root/shoot ratios of ryegrass. The E+ plants showed a greater shoot and lower root avoidance to dehydration stress than the E− plants. The negative values of relative interaction intensity index between the diploid ryegrass and AR29 endophyte association suggested that these host-endophyte associations were parasitic under intermittent soil wetting-drying cycles. While the nitrogen (N) and phosphorus (P) concentration, plant production index, and water-use efficiency were significantly greater in E+ plant than in E− plants, the N and P efficiency ratios were greater in E− plants than in E+ plants. Results suggested that the endophyte mediation may have synergistic or antagonistic effects which depend on particular host genotype-endophyte combinations and environmental conditions to promote drought tolerance in grasses for degraded land restoration or forage production.

Grasses are excellent candidates for phytoremediation because of their high biomass production, high adaptability and low management cost. This study assesses interspecific variation of cadmium (Cd) phytoextraction capabilities in eight C3 grass species. Populations of 30‐day‐old C3 grass species – namely, Agrostis alba, Anthoxanthum odoratum, Dactylis glomerata, Festuca arundinacea, Festuca pratensis, Lolium multiflorum, Lolium perenne and Poa pratensis– were grown hydroponically for 15 days with different concentrations of Cd (0, 5, 10 and 50 µM). For each species, shoot biomass, the proportion of growth inhibition (GI, %), shoot Cd concentration and accumulation, shoot nutrient uptake, and the proportion of uptake inhibition (UI, %) of nutrient minerals were evaluated. Effects of Cd application included stunted growth. The GI increased from 5% to 70% with an increase in Cd concentrations. For all Cd treatments, L. multiflorum showed the highest shoot dry biomass. Shoot Cd concentrations negatively affected mineral nutrient uptake. The highest Cd treatment caused UI of various elements of 37–95%. Under 50‐µM Cd treatment, Cd accumulation varied by 20 times among species, and L. multiflorum showed the highest Cd accumulation (116.46 µg plant−1). Our results indicate that L. multiflorum exhibited high degrees of both Cd tolerance and Cd phytoextraction capacity among grass species.