Epigenetics is a scientific field in high fashion and moving fast nowadays. Although the term was coined in 1942 by C. H. Waddington and scientists have been working since to elucidate the mechanisms involved, it is only recently that the mainstream media has been inundated by articles on epigenetic themes.
Very concise and without details, the field of epigenetics deals with the modifications induced by various external factors on any given organism and their consequences. The actual genetic making of the organism is not changed; epigenetic modifications only affect how various genes are expressed and are switch on or off (“epi” means “above” in Greek hence the epigenetics = factors beyond the genetic code. Most importantly, some of these changes can be inherited from a generation to another.
Referring strictly to plants, the study of epigenetics is underway and there is still much to learn.
I’ve read that “Plants are masters of epigenetic regulation” and it is not hard to understand why: they cannot move, so they have no choice but to adapt continuously to the changing environment and other stimuli.
Silene compacta in habitat
On a practical level, we can speculate that the epigenetics explains why some species and especially those living in extreme habitats (alpine regions, deserts…) are some of the hardest to adapt to garden cultivation even when provided with close by conditions.
Also, epigenetics might explain the differences in germination patterns of a given species, in case of mother-plants originating from different geographical areas.
It is already known by gardeners that the more different your climate & garden conditions are than the ones where a species grows wild, the more difficult it will be to ‘tame’ it into cultivation and hardiness is not the only factor.
The first generation of seedlings express the traits inherited from the mother-plant and they react accordingly in relation to seasonal temperatures, substrate, light intensity, water regime…..
By growing a second generation seedlings from the first ones, and then a third one and so on….we have increasingly higher chances to obtain better ‘tamed’ plants for our specific garden conditions. They will look exactly the same as the original mother-plant, but their adaptation to the local variations in temperatures, water regime, humidity and so on, will be improved.
To exemplify:
Last summer, Helichrysum arenarium (sandy everlasting) successfully flowered in my rockery and set a few seeds; later in the fall it ‘disappeared’ despite growing in a very well drained spot.
Helichrysum arenarium ex. Dobrogea, flowering in August, 2021
The species was grown from wild collected seeds in the Dobrogea region of Romania, which has a very different climate than we have in SW Ontario, so it was no big surprise that it didn’t last long.
It is a very lucky situation when a few seeds are available to obtain a second generation of seedlings. There is hope that they will adapt better to the new environment in the next generation.
Other species also managed only a first flowering: Paronychia cephalotes, a couple of Minuartia and Centaurea jankae.
But others grown from seeds from the same trip adapted well: Dianthus nardiformis, Centaurea orientalis, Alyssum borzeanum, Aurinia saxatilis, Sedum urvillei, Silene compacra, Ephedra distachya and Iris suaveolens.
Virtual traveling to the region in question available below:
Winter getaway – Dobrogea I
Winter getaway – Dobrogea II
And/or read more about epigenetics in plants (there are many other articles available).
Epigenetic Regulation in Plants
