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Environmental benefits can be achieved by organic farming systems; however, weed pressure and timely crop nutrition remain important drawbacks for many field crops. Agroecological practices, such as double cropping (e.g., intercropping and relay cropping), using forage legume species can provide nitrogen (N) to the companion crop through biological N fixation and tackle weed issues by competing for light, water and land. The present study investigated the effect of intercropping (IC) and relay-cropping (RC) systems of durum wheat (Triticum turgidum subsp. durum (Desf.) Husn) and forage legumes (Trifolium subterraneum L., Medicago polymorpha L., and Lotus corniculatus L.) by varying organic N fertilization with the aim to reduce N-requirement and weed pressure and increase wheat grain yield and grain protein content in Mediterranean organic farming systems. N fertilizer significantly improved wheat grain yield and grain protein, while a null effect on legume and weed biomass yields was found. Double cropping (T. durum-M. polymorpha, and T. durum-L. corniculatus) enhanced wheat grain yield as compared to the control and the T. durum-T. subterraneum. IC significantly improved legume yield, grain protein and the land equivalent ratio (LER) and reduced weed dry biomass as compared with the RC and the control. Among legume species, T. subterraneum outperformed the others and was less affected by the wheat’s competitive performance. Nonetheless, M. polymorpha was as effective as T. subterraneum in controlling weeds. Weed dry biomass was linearly reduced by increasing legume yield; the relationship improved by cumulating wheat grain yield to legume yield. Overall, this study indicated that double cropping, especially IC, can be a suitable agroecological practice to tackle weed issues and reduce N-requirement in Mediterranean organic cereal-based systems.

The present work compared the agronomic traits, chemical composition, fatty acid profile, and in vitro fermentation characteristics of twelve accessions of Amaranthus spp., belonging to A. cruentus, A. hybridus, A. hypochondriacus, and A. tricolor, grown in a semiarid Mediterranean area. Among accessions, Benin and Arizona (A. cruentus) and Pennsylvania (A. hypochondriacus) showed the highest seed yield (on average, 322.1 g m−2), while Taiwan (A. tricolor) and India and Iowa (A. hypochondriacus) the highest thousand seed weight (on average, 0.81 g). Among the species, A. hypochondriacus showed the highest crude protein (16 g 100g−1), starch (51.5 g 100g−1), and soluble detergent fiber (2.03 g 100g−1) contents and the most favorable in vitro fermentation characteristics with the highest short-chain fatty acid (SCFA 52.6 mmol g−1) and butyric acid (20.7% SCFA) production together with the lowest crude fiber (4.93 g 100g−1) and insoluble dietary fiber (12.5 g 100g−1) content. Arizona (A. cruentus) showed the highest level of monounsaturated fatty acids (32.67 g 100g−1), Ohio (A. hybridus) had the highest levels of polyunsaturated fatty acids (44.62 g 100g−1) and n6-PUFA (44.21 g 100g−1), and India (A. hypochondriacus) had the highest level of n3-PUFA (0.63 g 100g−1). A. hypochondriacus exhibited not only desirable nutritive characteristics, agronomic traits, and suitability to Mediterranean growing conditions, but also a potential beneficial effect. Nonetheless, it is recommended to run longer-term field trials to confirm these findings and to assess the genotype by environment interaction either with current accessions or others from the wide Amaranth germplasm available.

Interest in white lupine has increased in recent years in animal nutrition due to its balanced protein and lipid content, phytochemical compounds, and low alkaloid content. Agronomic traits, nutrients, and antioxidant phenols of six white lupin genotypes grown in a Mediterranean area were explored. Genotypes significantly differed in growth stages and life cycle length (from 172 to 204 days after sowing), plant height (from 36.1 to 97.2 cm), seed yield (from 1.02 to 3.50 Mg ha−1), and yield components. Seed yield was positively correlated with the number of seeds per pod and the thousand-seed weight. Across the average of genotypes, a high protein content (397 g kg−1), a low fiber content (133 g kg−1), and oil content (116 g kg−1) with a high oleic acid (453–509 g kg−1) and low erucic acid content (8–17 g kg−1) were found. The n3/n6 ratio varied from 1:1 to 1:4. Ecotype G showed the highest TPC, DPPH•, and ABTS•+ and Multitalia showed the highest content of Apigenin 1 and 2 derivatives. The lowest alkaloid content was recorded in Volos, Luxor, and Lublanc. Overall, this species can be considered a suitable feed crop and a valuable ingredient in animal nutrition due to its overall nutritional profile. At present, only Volos, Luxor, and Lublanc can be suggested in animal nutrition due to the low alkaloid content. Nonetheless, interesting agronomic and quality traits in Multitalia and the two ecotypes suggest room for breeding to reduce their antinutritional factors.