Heracleum Mantegazzianum Research Articles

Cytoplasmic fibres associated with streaming and saltatory-particle movement in Heracleum mantegazzianum

The giant cells of the petiolar hairs of Heracleum mantegazzianum contain cytoplasmic fibres that are readily visible with phase contrast or interference contrast optics. These fibres are associated with saltatory particle movement and protoplasmic streaming in this cell and are believed to be the living image of similar fibres reported in electron micrographs of a variety of cell types.

Preliminary Investigations of Heracleum Mantegazzianum

Preliminary investigations of the air-dried roots of Heracleum mantegazzianum grown under greenhouse conditions were conducted. Seed germination requires moist cold treatment. The germination rate appears to be directly related to the length of the moist cold period. Gibberellin seed treatment did not substitute for the cold requirement. Thin-layer chromatography revealed the presence of 6 coumarins which were tentatively identified as bergapten, isobergapten, pimpinellen, isopimpinellen, sphondin, and umbelliferone. Results also indicate that the plant can cause photosensitization.

Über den Zuckergehalt der Siebröhren- bzw. Siebzellensäfte von Heracleum Mantegazzianum und Picea abies (L.) KARST.

Sieve-tube sap from the petioles of Heracleum Mantegazzianum and Picea abies stems was obtained by severing the proboscides of aphids tapping the sieve tubes of these plants. Sucrose was the only sugar detected in the sieve-tube sap, and occurred at concentrations of 24% (Heracleum) and 10% (w/v) (Picea). Volumes of sieve-tube sap equal to 5500 sieve-tube cells of Heracleum and 50 sievetube cells of Picea exuded from severed aphid probiscides. The mouth-parts of the aphids living within hollow Heracleum petioles normally penetrate the xylem of the vascular bundles in order to reach the phloem sieve-tubes. The aphids also tap the sievetubes of isolated phloem strands.