The ecosystem dehesa, which exceeds 3.5 million hectares in the South-West of the Iberian peninsula, is a peculiar silvopastoral system and generally well preserved. It is greatly extensive and has a high environmental value due to the low impact of human activity on the Mediterranean forest. The dehesa is mainly located in semi-arid areas over acid or neutral soils with a restricted production potential. Results of this investigation on the quality and production of the herbaceous pastures (1500 to 2700 kg DM/ha), improvement of systems (introduction of species and fertilization of sown and natural pastures), management (extensive grazing), fruit production (670 kg DM/ha acorn) and distribution so it can be used by pigs, erosion control and so on are reported and discussed. The extensive set stocking rate is very dependent on the ecosystem (ruminant and monogastric animals). The dehesa must be considered as an ecosystem resulting from extensive stocking, taking into account that the best way to keep it is by means of production.

In order to improve the nutritional value of two-rowed barley grain, two foliar selenium (Se) fertilizers (sodium selenate and sodium selenite) at four rates (0-10-20-40 g/ha) were applied during the growing seasons 2010/2011 and 2011/2012 in a field experiment conducted under semiarid Mediterranean conditions. The grain harvested in the 2010/2011 season accumulated a greater amount of total Se than the grain of the 2011/2012 season. Sodium selenate was much more effectively taken by plants than sodium selenite, and there was a strong and linear relationship between total Se concentration and Se rate in both sodium selenate and selenite. For each gram of Se fertilization, applied as sodium selenate or sodium selenite, the increases of total Se concentration in grain were 44 and 9 μg/kg dry weight, respectively. No increments in total or available Se were observed in soil after harvesting even at the highest doses of either fertilizer. It can be concluded that two-rowed barley would be a good candidate to be included in biofortification programs under Mediterranean conditions to increase Se in animal feeding and in the human diet through beer production.

Millions of people have an inadequate supply of selenium (Se) and Se-biofortified crops could prevent such deficiency. In order to establish an effective Se biofortification program under Mediterranean conditions on wheat, the objective of the present study was to evaluate the effect of the Se application timing on the Se accumulation in the grain, yield and protein content. In a field experiment, ten g ha -1 of sodium selenate were foliar-applied at four different growth stages: at 1 st node detectable (GS-31); at 5 th node detectable (GS-35); at boots just swollen (GS-45); and at 1 st spikelet visible (GS-51), in two different growing seasons, 2010-2011 and 2011-2012. The application of Se between GS-35 and GS-45 produced the highest Se accumulation in grain, especially in humid years. The milling process caused Se losses of about 15%. In the special conditions of the Mediterranean area, a proper timing of Se application might have major importance in the Se accumulation in the grain, but due to the rainfall before application, rather than to the plant growth stage.

Agronomic zinc (Zn) biofortification of crops could help to alleviate dietary Zn deficiency, which is likely to affect more than one billion people worldwide. To evaluate the efficiency of agronomic Zn biofortification of broccoli, four application treatments were tested: no Zn application (control); soil application of 5 mg/kg ZnSO₄·7 H₂O (soil); two sprays (15 mL/pot each) of 0.25% (w/v) ZnSO₄·7 H₂O (foliar); and soil + foliar combination. Soil Zn application increased Zn-DTPA (diethylenetriamine pentaacetic acid) concentration by 3.7-times but did not affect plant growth or plant Zn concentration. Foliar Zn application increased stem + leaves and floret Zn concentration by 78 and 23 mg Zn/kg, respectively, with good bioavailability based on phytic acid concentration. Boiling decreased mineral concentration by 19%, but increased bioavailability by decreasing the phytic acid concentration. The entire broccoli could constitute a good nutritional source for animals and humans. An intake of 100 g boiled florets treated with the foliar treatment will cover about 36% of recommended dietary intake (RDI) of Zn, together with 30% of Ca, 94% of K, 32% of Mg, 6% of Na, 55% of P, 60% of S, 10% of Cu, 22% of Fe, 43% of Mn, and 35% of Se RDIs.

The objective of the present study was to evaluate the effect of P, Ca, S, and/or K and/or Mg application at different rates on the botanical composition, herbage yield and its nutritive value in dehesas developed on calcareous soils. In two growing seasons, 2009/10 and 2010/11, five surface-broadcast fertiliser treatments were applied once in autumn. Two grazing periods were simulated by cutting the pasture in mid-spring and late-spring. Treatment K1, with the highest amount of Ca and without K in its composition, provided higher crude protein values in the herbage than controls in 2009/10. When the effect of each nutrient was analysed separately, a strong and highly positive response of Mg application on herbage production was recorded. A surface application of fertilisers containing 25 kg Mg/ha in autumn could increase herbage yield by 40% under the studied conditions. However, Mg was not applied alone, and thus this increase could be due to an effect of Mg by itself or to a synergistic effect between Mg and other nutrients applied. The application of Ca, P and Mg may also favour the production of high-quality forage by yielding a greater cover of legumes and digestible protein.