In some European community countries up to 8% of the agricultural area is managed organically. The aim was to obtain a metabolite profile for wheat (Triticum aestivum L.) grains grown under comparable organic and conventional conditions. These conditions cannot be found in plant material originating from different farms or from products purchased in supermarkets. Wheat grains from a long-term biodynamic, bioorganic, and conventional farming system from the harvest 2003 from Switzerland were analyzed. The presented data show that using a high throughput GC-MS technique, it was possible to determine relative levels of a set of 52 different metabolites including amino acids, organic acids, sugars, sugar alcohols, sugar phosphates, and nucleotides from wheat grains. Within the metabolites from all field trials, there was at the most a 50% reduction comparing highest and lowest mean values. The statistical analysis of the data shows that the metabolite status of the wheat grain from organic and mineralic farming did not differ in concentrations of 44 metabolites. This result indicates no impact or a small impact of the different farming systems. In consequence, we did not detect extreme differences in metabolite composition and quality of wheat grains.

We showed recently that antisense plants with decreased activity of the plastidic ATP/ADP-transporter protein exhibit drastically reduced levels of starch and a decreased amylose/amylopectin ratio, whereas sense plants with increased activity of the transporter possessed more starch than wild-type plants and an increased amylose/amylopectin ratio. In this paper we investigate the effect of altered plastidic ATP/ADP-transporter protein expression on primary metabolism and granule morphology in more detail. Tuber tissues from antisense and sense plants exhibited substantially increased respiratory activity compared with the wild type. Tubers from antisense plants contained markedly increased levels of free sugars, UDP-Glc, and hexose phosphates, whereas phosphoenolpyruvate, isocitrate, ATP, ADP, AMP, UTP, UDP, and inorganic pyrophosphate levels were slightly decreased. In contrast, tubers from sense plants revealed a slight increase in adenine and uridine nucleotides and in the levels of inorganic pyrophosphate, whereas no significant changes in the levels of soluble sugars and metabolites were observed. Antisense tubers contained 50% reduced levels of ADP-Glc, whereas sense tubers contained up to 2-fold increased levels of this sole precursor for starch biosynthesis. Microscopic examination of starch grain morphology revealed that the size of starch grains from antisense tubers was substantially smaller (50%) compared with the wild type. The large starch grains from sense tubers appeared of a more angular morphology, which differed to the more ellipsoid shape of wild type grains. The results suggest a close interaction between plastidial adenylate transport and starch biosynthesis, indicating that ADP-Glc pyrophosphorylase is ATP-limited in vivo and that changes in ADP-Glc concentration determine starch yield, as well as granule morphology. Possible factors linking starch synthesis and respiration are discussed.

hydroponic culture have greater access to N than those grown in pots. Regardless of the culture method, CO 2 enrichment has a direct eect on NR mRNA stability.Abbreviations: Asn = asparagine; Asp = aspartate; Gln = glutamine; Glu = glutamate; GS = glutamine synthetase; GUS = b-glucuronidase; NR = nitrate reductase; PEPCase = phospho-

Photosynthetic carbon assimilation, carbon partitioning and foliar carbon budgets were measured in the leaves of transformed tomato plants expressing a maize sucrose-phosphate synthase (SPS) gene in addition to the native enzyme, and in untransformed controls. The maize SPS gene was expressed under control of either the promoter of the small subunit of ribulose 1,5-bisphosphate carboxylase (rbcS promoter; lines 2, 9 and 18) or the 35S promoter from cauliflower mosaic virus (CaMV promoter; line 13). The rate of sucrose synthesis was increased relative to that of starch and sucrose/starch ratios were higher throughout the photoperiod in the leaves of all plants expressing high SPS activity. The leaf carbon budget over the day/night cycle in air at low irradiance (180μmol photon m−2 s−1) was similar in all plants. Net photosynthesis measured in air and at elevated CO2 (800–1500 μl l−1) on whole plants grown in air at 400μmol m−2 s−1 irradiance was significantly increased in the high SPS expressors compared to the untransformed controls and was highest where SPS activity was greatest. At high CO2 the stimulation of photosynthesis was more pronounced. We conclude that SPS activity is a major point of control of photosynthesis particularly under saturating light and CO2.

Tropical African yambean (Sphenostylis stenocarpa L) is an under-utilised hardy, protein-rich legume. Antinutrients and the excessively long cooking time (4-6 h), among other factors, limit the food use of African yambean seeds. To reduce these limitations, non-traditional, less energy-consuming processing methods are required. Seeds of different varieties were (i) examined for ingredients and (ii) fermented with Lactobacillus plantarum. Comparisons with traditionally cooked beans were made. Protein content and in vitro protein digestibility were increased slightly by fermentation or cooking. Reductions in trypsin and α-amylase inhibitor activity and tannin ranged from significant to complete. The contents of potentially very toxic cyanogenic glycosides and flatulence-causing α-galactosides were high in raw beans. Reduction by fermentation (by 85%) was clearly more effective than by traditional cooking (10-20%). The results demonstrate (i) that fermentation can substantially improve the nutritional quality and (ii) that the energy requirement to produce a basic consumable fermented food from African yambean is only 10% of that of traditional cooking. On these grounds, widespread application of lactic acid fermentation by individuals or small-scale industries would be advantageous in the context of small-household economy, environmental protection, health and long-term sustainable agriculture in Nigeria.