The Variegated Plants Phenomenon
Plants with albinism, also known as variegated plants - a new trend that you see all over social media. But how does this phenomenon happen?
How do plants become variegated?
As the green colour in plants is caused by the presence of chlorophyll, the white leaves arise when there is an absence of pigment in the chloroplast. This mutation originates from anomalies at different stages of the synthesis of chloroplasts by the plant. These genetic mutations can be at the level of the genome of the whole plant, or they can be present only in certain cells or organs of the plant.
Different types of variegations
It is with this basis that we can explain the different major types of existing varieties!
In many occasions, the variegations are not necessarily a mutation, but a natural characteristic pigmentation selected by horticulturists to obtain coloured species from generation to generation.
At the plant level, we assume that certain areas of the leaf will produce chloroplasts containing chlorophyll and others will not. These cells are genetically different. Depending on whether this genetic mutation is expressed in the meristems (these are the nodes from which new leaves are generated), or various other plant organs, decides whether a variety is stable or unstable, and transmissible between plant generations or not.
Often only the meristem presents the mutation and therefore, it cannot be transmitted to the progeny. A number of varieties can be induced by viruses. Indeed, either by deleterious effect on the nutrition of the plant, or by the induction of modification of the expression of the genes, the viruses can be at the origin of very particular phenotypes. In most cases, it is best to isolate diseased plants to avoid contaminating your collection. However, some cultivars are said to have been obtained from viral mutations. This is the case with some Hostas, for example.
The Mosaic virus
Lately, a virus has been in the news a lot: the mosaic virus, or Dasheen Mosaic Virus (DsMV). Attacking many families of plants, it is found in particular in Araceae. It is characterised by discolouration appearing in all the veins of the leaf. It was made "popular" when sales of variegated Monstera adansonii exploded. This plant, produced in large numbers in its green form, has seen subjects attacked by the mosaic virus. This mimics variegations, and therefore sells for exorbitant prices. It seems that a certain number of Monstera adansonii have been sold as variegata or "mint" when it was in fact only a diseased plant. However, this virus cannot be cured, is transmitted to many plant families and relatively weakens the plant.
In addition, it should be noted that the "true" variegata often present unstable variegations. There are stable variants of cultivars, but they are very rare.
So be careful if you want to invest in a variegated plant at a rather expensive price!