Articles
CHANGES IN PLANTS ORIGINATING FROM MIXED CULTURES
We used callus pieces and homogenates as well as small sections of organs, 12 mm in size. Capsicum annuum, Solanum tuberosum, Solanum melongena, Solanum dulcamara and Solanum nigrum (black night-shade) were the main test objects. Solanum nigrum was the standard component and other species mentioned were added to it alternately, but variants consisting of 34 or even more constituents also occurred.
We made an effort to keep the number of cells of species on the same level in mixed cultures which were transferred, supplemented and mixed repeatedly.
This procedure lasted two years at least.
On proliferating media intermediary shoots appeared beside normal ones.
Although black night-shade type is dominating over intermediary plantlets, they bear some characters of partner species (e.g. paprika, potato) too.
These plants of S. nigrum – C. annuum combination remind on paprika in following features: shape of leaf, strength of stem, structure of branching, number of flowers per raceme.
In addition transitional individuals have bigger and brighter berries which contain significantly less anthocyanins compared to those of black night-shade.
Intermediates originating from S. nigrum – S. tuberosum mixed cultures look similar to potato in characters listed: shape of leaf, position of pistil to stamens and sepals to berries, appearance of accessory petals, size of reproductive organs, high frequency of sterile flowers.
Most of the characters mentioned show maternal inheritance in F1 and F2 generations of hybrid-like plantlets, which refers to cytoplasmic transfer of genes.
Although explanation of the phenomenon requires further investigations, we may suspect that mixed cultures initiate hereditary changes.
Preliminary DNA-analysis (RAPD) did not exclude this possibility.