The problem of misidentification between edible and poisonous wild plants: Reports from the Mediterranean area.

Today, in many European countries, people are looking for wild edible plants to experience new tastes and flavors, by following the new trend of being green and environmentally friendly. Young borage and spinach leaves can be easily confused by inexpert pickers with those of other plants, including poisonous ones, such as Mandragora autumnalis Bertol. (mandrake) or Digitalis purpurea L. (foxglove), common in southern and northern Italy respectively. In the last twenty years, several cases of intoxication by accidental ingestion of mandrake and foxglove have been reported. The purpose of this work was to perform a pharmacognostic characterization of young leaves from borage, mandrake, foxglove and spinach, by micro-morphological, molecular and phytochemical techniques. The results showed that each of the three techniques investigated could be sufficient alone to provide useful information for the identification of poisonous species helping the medical staff to manage quickly the poisoned patients. However, the multi-disciplinary approach proposed could be very useful to asses the presence of poisonous plants in complex matrices, to build a database containing morphological, molecular and phytochemical data for the identification of poisonous species or in forensic toxicology, given their increasingly frequent use due to their low cost and relatively common availability.

Two genes encoding distinct cytosolic glutamine synthetases are closely linked in the pine genome.

The major isoenzyme of glutamine synthetase found in leaves of angiosperms is the chloroplastic form. However, pine seedlings contain two cytosolic glutamine synthetases in green cotyledons: GS1a, the predominant isoform, and GS1b, a minor enzyme whose relative amount is increased following phosphinotricin treatment. We have cloned a GS1b cDNA, and comparison with the previously reported GS1a cDNA sequence indicated that they correspond to separate cytosolic GS genes encoding distinct protein products. Phylogenetic analysis showed that the newly reported sequence is closer to cytosolic angiosperm GS than to GS1a, suggesting therefore that GS1a could be a divergent gymnospermous GS1 gene. Gene mapping using a F2 family of maritime pine showed co-localization of both GS genes on group 2 of the genetic linkage map. This result supports the proposed origin of different members of the GS1 family by adjacent gene duplication. The implications for gymnosperm genome organization are discussed.