Agricultural potential of Mediterranean grain and forage legumes: 2) Anti-nutritional factor concentrations in the genus Vicia

As part of an investigation into the agricultural potential of under-exploited Mediterranean Viceae, anti-nutritional factor concentrations were measured in the seed of 7 species. These included: V. sativa(subsp. amphicarpa(L.) Batt., subsp. macrocarpa(Moris) Arcang, subsp. nigra(L.) Ehrh., subsp. sativa), V. ervilia L., V. faba L. (var. faba, var. minor Peterm.), V. narbonensis L. (var. aegyptiaca Kornhuber ex Asch. et Schweinf., var. affinis Kornhuber ex Asch. et Schweinf., var. jordanica H. Schaef., var. narbonensis, var. salmonea(Mout.) H. Schaef.), and relatives, including V. johannis Tamamsch., (var. johannis, var. procumbens H. Schaef.), V. hyaeniscyamus Mout., and V. serratifolia Jacq. Both quantitative and qualitative differences in seed chemistry were observed. Condensed tannins, phenolics and proteinase inhibitors were found in varying concentrations in all taxa. The highest concentrations of phenolic secondary metabolites (0.8–1.4% leucocyanidin equivalents, 9.5–16.4 mg/g phenolics) were found in V. faba, the V. narbonensis relatives and V. sativa subsp. macrocarpa. These taxa also tended to contain low levels of proteinase inhibitors (0.25-0.55 mg trypsin/mg protein), whereas the opposite was the case for V. ervilia(2.1 mg t/mg p). V. narbonensis was intermediate both in terms of tannin and proteinase inhibitor levels. In contrast, the non-protein amino acids tended to be more specific in their distribution. Concentrations of canavanine varied from 0.04-0.11% in the seed of V. ervilia, and may constrain the end-use of the grain, given that pigs are sensitive to concentrations as low as 0.08% in their diet. In V. sativa variation of -glutamyl--cyanoalanine within and between subspecies (0.41–1.36%) is not sufficient to make the grain palatable to monogastrics, since > 0.075% inclusion in the diet causes mortality in chicks. In V. narbonensis, there was no significant variation between most varieties for -glutamyl-S-ethenyl cysteine (GEC), a non-protein amino acid peptide which reduces grain palatability. However, lower concentrations were found in V. n. var. jordanica and its near relatives, V. johannis, V. hyaeniscyamus and V. serratifolia(1.3-1.6%, compared with 1.9+/–0.02% in all remaining V. narbonesis sub-species). Anti-nutritional factor concentrations were used to visualize taxonomic relationships using hierarchical cluster analysis. The V. narbonensis varieties were closely aligned with their near relatives, V. johannis, V. hyaeniscyamus and V. serratifolia. In contrast V. faba was positioned closer to the V. sativa subspecies than either to V. narbonesis or its near relatives. V. ervilia was the most distantly related species. Across all taxa proteinase inhibitors and condensed tannins or total phenols were negatively correlated (r=– 0.72, P < 0.009). This may be a mechanism which minimizes wasteful resource allocation to chemical defense, because the 2 anti-nutritional factors are functionally substitutable, since they both reduce the availability of protein in plant material. Thus taxa investing in high concentrations of proteinase inhibitors do not duplicate chemical defense mechanisms by simultaneously producing large amounts of tannins and phenolics.     

A forage grass and small grain legume plant collecting expedition in South East Poland, 1990

Summary The Plant Genetic Resources Unit (PGRU) of the Institute of Grassland and Environmental Research, Welsh Plant Breeding Station (IGER, WPBS), UK, and the Plant Genetic Resources Section of the Plant Breeding and Acclimatization Institute (PBAI), Poland, carried out a joint collecting expedition in Poland between 25 August and 7 September 1990. The expedition was unique in that it was the first time that vegetative sampling had been applied to the perennial forage grass and legume populations of south east Poland. The expedition focused on seminatural vegetation in agriculturally managed situations and detailed collection site data on management systems was obtained from landowners.Samples were collected from 62 sites. Vegetative collections of Lolium spp. (37 populations) and Trifolium spp. (56 populations), and seed collections of Festuca spp. (32 populations) were made by the IGER team (Table 2). The PBAI team made 59 separate seed collections, mainly of Leguminosae.The expedition covered four geographical subregions of south east Poland. (See Fig. 1). These were the Nizina Mazowiecka south of Warszawa, the Wyzyna Malopolska with the town of Kielce at its centre and the Beskidy Zachodnie and Beskidy Wschodnie regions of the Carpathian mountains.A diverse range of habitats was sampled covering a broad range of altitude agricultural management systems and ecological conditions. Polish agriculture is faced with the problems of a rapid orientation to a market economy and it is likely that the diverse range of habitats encoutered will be reduced as agricultural practices change. This will lead to genetic erosion of the unique forage grass and legume populations to be found in Poland.Abbreviations ECP/GR European Co-operative Programme on Crop Genetic Resources - IGER Institute of Grassland and Environmental Research - PBAI Plant Breeding and Acclimatization Institute - PGRU Plant Genetic Resources Unit - WPBS Welsh Plant Breeding Station