Summary1 Ecological and agronomic research suggests that increased crop diversity in speciespoor intensive systems may improve their provision of ecosystem services. Such general predictions can have critical importance for worldwide food production and agricultural practice but are largely untested at higher levels of diversity. 2 We propose new methodology for the design and analysis of experiments to quantify diversity-function relationships. Our methodology can quantify the relative strength of inter-specific interactions that contribute to a functional response, and can disentangle the separate contributions of species richness and relative abundance. 3 Applying our methodology to data from a common experiment at 28 European sites, we show that the above-ground biomass of four-species mixtures (two legumes and two grasses) in intensive grassland systems was consistently greater than that expected from monoculture performance, even at high productivity levels. The magnitude of this effect generally resulted in transgressive overyielding. 4 A combined analysis of first-year results across sites showed that the additional performance of mixtures was driven by the number and strength of pairwise inter-specific interactions and the evenness of the community. In general, all pairwise interactions contributed equally to the additional performance of mixtures; the grass-grass and legume-legume interactions were as strong as those between grasses and legumes. 5 The combined analysis across geographical and temporal scales in our study provides a generality of interpretation of our results that would not have been possible from individual site analyses or experimentation at a single site. 6 Our four-species agricultural grassland communities have proved a simple yet relevant model system for experimentation and development of methodology in diversity-function research. Our study establishes that principles derived from biodiversity research in extensive, semi-natural grassland systems are applicable in intensively managed grasslands with agricultural plant species.

Summary 1.A coordinated continental-scale field experiment across 31 sites was used to compare the biomass yield of monocultures and four species mixtures associated with intensively managed agricultural grassland systems. To increase complementarity in resource use, each of the four species in the experimental design represented a distinct functional type derived from two levels of each of two functional traits, nitrogen acquisition (N 2 -fixing legume or nonfixing grass) crossed with temporal development (fast-establishing or temporally persistent). Relative abundances of the four functional types in mixtures were systematically varied at sowing to vary the evenness of the same four species in mixture communities at each site and sown at two levels of seed density. 2. Across multiple years, the total yield (including weed biomass) of the mixtures exceeded that of the average monoculture in >97% of comparisons. It also exceeded that of the best monoculture (transgressive overyielding) in about 60% of sites, with a mean yield ratio of mixture to best-performing monoculture of 1Á07 across all sites. Analyses based on yield of sown species only (excluding weed biomass) demonstrated considerably greater transgressive overyielding (significant at about 70% of sites, ratio of mixture to best-performing monoculture = 1Á18).3. Mixtures maintained a resistance to weed invasion over at least 3 years. In mixtures, median values indicate <4% of weed biomass in total yield, whereas the median percentage of weeds in monocultures increased from 15% in year 1 to 32% in year 3. 4. Within each year, there was a highly significant relationship (P < 0Á0001) between sward evenness and the diversity effect (excess of mixture performance over that predicted from the monoculture performances of component species). At lower evenness values, increases in community evenness resulted in an increased diversity effect, but the diversity effect was not significantly different from the maximum diversity effect across a wide range of higher evenness values. The latter indicates the robustness of the diversity effect to changes in species' relative abundances. 5. Across sites with three complete years of data (24 of the 31 sites), the effect of interactions between the fast-establishing and temporal persistent trait levels of temporal development was highly significant and comparable in magnitude to effects of interactions between N 2 -fixing and nonfixing trait levels of nitrogen acquisition. 6. Synthesis and applications. The design of grassland mixtures is relevant to farm-level strategies to achieve sustainable intensification. Experimental evidence indicated significant yield benefits of four species agronomic mixtures which yielded more than the highest-yielding monoculture at most sites. The results are relevant for agricultural practice and show how grassland mixtures can be designed to improve resource complementarity, increase yields and reduce weed invasion. The yield benefits were robust to considerable changes in the relative propo...

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Grazing animals walk outdoors and harvest fresh herbage from a three‐dimensional canopy. Botanical composition and grassland management in various farming systems affect herbage intake and milk fatty acid (FA) composition. Grazing animals encounter a vertical gradient while grazing down a sward; responses in milk FA composition are discussed. Grazing animals have diets rich in poly‐unsaturated fatty acids (PUFA), particularly α‐linolenic acid (C18:3n‐3). Concentrates and starch‐rich fodders affect rumen retention time of the feed, increase linoleic acid (C18:2n‐6) intake, and alter biohydrogenation pathways toward less n‐3 PUFA and less rumenic acid (conjugated linoleic acid (CLA) isomer C18:2c9t11), leading to lower contents of these compounds in the milk. Milk from grazing‐based production systems including organic systems, therefore, has less saturated and more n‐3PUFA and CLAc9t11 which is considered beneficial for health. The occurrence of natural trans FA (t11) in milk predominates with grazing whereas intensive feeding practices enhance t10‐FA, with possible negative health effects. FA intake – output relations can differ among plant species due to rapid rumen passage rate or compounds protecting PUFA, resulting in more PUFA in milk. Methodological constraints for FA measurement in herbages are discussed. Trends in grazing and dairy farming systems and implications for milk FA composition are addressed. Practical applications: Grazing is important for fresh forage intake, animal health and natural behaviour, landscape values and grassland biodiversity. Grazing is a political, societal and marketing issue in The Netherlands where retailers since 2011 sell dairy products labelled as “pasture‐milk” and dairies pay a premium to farmers whose cows get access to pasture. Grazing affects green leaf intake because animals can select. Pasture allowance enhances α‐linolenic acid and CLAc9t11 (rumenic acid) concentrations in milk fat. FA need to be designated by unique names; CLA is a generic term and isomers give rise to different biological responses. As some forbs reduce biohydrogenation, grassland species diversity may improve PUFA transfer efficiency from feed to milk. Trends in animal genetics and increased herd size, TMR feeding and automated milking systems cause reduction of grazing in Europe, which can increase saturated and trans‐10 milk FA concentrations and reduce naturally occurring fat‐soluble vitamins and antioxidants in dairy products. Grazing (pasture‐feeding versus indoor with conserved forage and concentrates) increases n‐3 PUFA and trans‐11 over trans‐10 FA in cow milk when cows can select, as leaves have high n‐3 PUFA concentrations; biodiverse grasslands enhance this effect as some forbs show less PUFA rumen biohydrogenation than grasses, thus increasing efficiency of PUFA transfer from forage to milk.

Carotenoids are isoprenoids widely distributed in foods that have been always part of the diet of humans. Unlike the other so-called food bioactives, some carotenoids can be converted into retinoids exhibiting vitamin A activity, which is essential for humans. Furthermore, they are much more versatile as they are relevant in foods not only as sources of vitamin A, but also as natural pigments, antioxidants, and health-promoting compounds. Lately, they are also attracting interest in the context of nutricosmetics, as they have been shown to provide cosmetic benefits when ingested in appropriate amounts. In this work, resulting from the collaborative work of participants of the COST Action European network to advance carotenoid research and applications in agrofood and health (EUROCAROTEN, www.eurocaroten.eu, https://www.cost.eu/actions/CA15136/ #tabsjName:overview) research on carotenoids in foods and feeds is thoroughly reviewed covering aspects such as analysis, carotenoid food sources, carotenoid databases, effect of processing and storage conditions, new trends in carotenoid extraction, daily intakes, use as human, and feed additives are addressed. Furthermore, classical and recent patents regarding the obtaining and formulation of carotenoids for several purposes are pinpointed and briefly discussed. Lastly, emerging research lines as well as research needs are highlighted.