Albinism:
Albinism is a genetic disorder where the plant lacks chlorophyll in most of its
structure, if not entirely. This results in pale yellow or even white coloration of the leaves
and stems due to the lack of green pigment necessary for photosynthesis.
Albinism in cannabis looks quite unique and interesting but is ultimately not good
for the plant’s health. Due to the lack of chlorophyll, the plant can’t produce energy
efficiently through photosynthesis and because of this the plant’s growth and
development will be hindered severely.
Some plants experience partial albinism where only some sections of the plant
lack chlorophyll. Plants with partial albinism can still produce some green leaves and
stems and are typically healthier than plants with full albinism. Despite being healthier
than plants with total albinism, partial albinism affected plants are still at risk of hindered
development and growth due to a lack of chlorophyll in many sections of the plant.
It is important to distinguish between true albinism and localized chlorosis and/or
light bleaching. Close proximity to high powered grow lights can destroy chlorophyll
pigments which causes leaves and flowers to turn white or to “bleach.” If your plant is
experiencing light stress induced albinism it is possible to remedy the situation by
turning down the light intensity, moving the light higher away from the plant or both
whereas a plant with true albinism will not be able to be helped in this way.
Environmental stress can lead to albinism in cannabis as there has been some
data that suggests that temperature stress (high heat specifically) can denature
pigment-producing enzymes. Cold stress has been shown to inhibit chlorophyll
synthesis as well. As mentioned above, these reasons may just be environmental stress
rather than true albinism.
True albinism is a recessive genetic trait and is undesirable due to its negative
impact on plant health and thus final yield and resin production. If a plant is truly albino
then there is no remedy as it is a genetic defect.
Luckily for growers, albinism is quite rare and thus not a common issue many will
ever have to deal with.
Fox-Tailing:
Have you ever noticed long, thin spires of calyxes stacked in a small pillar on top
of or growing away your bud? If so, then you have seen firsthand what “fox-tailing” in
cannabis looks like.
“Fox-tailing”, also known as a second internode bloom, is one of the more
common “mutations” growers see in their garden. Even though fox-tailing is more of aphenotypic trait/growth pattern rather than a true mutation, it can be genetic in some
cases. Many growers have experienced this morphology, particularly when temps are
too high, lights are too intense, or the sativa is too stressed out.
There are several causes of fox-tailing in cannabis. As mentioned above,
excessively high heat (temps above 77-80 0 F) can trigger fox-tailing as well as excessive
light stress. In many cases, when light intensity exceeds 1,000 PPFD (without CO 2
supplementation) it can cause stress to a cannabis plant and can cause it to fox-tail.
Another cause of fox-tailing is the plant’s genetics. Some strains, particularly
sativas, are prone to having a few fox-tails regardless of whether grow conditions were
optimal or not. Generally, commercially available strains are not bred for this trait as it is
seen as largely undesirable for most cultivators, but some strains end up having
something special enough about them (terpene profile, effect, yield, overall plant vigor,
etc.) to release regardless of the fox-tail trait. A little research into a particular strain can
save a grower a lot of time if they do not want to see fox-tails in their garden. Seed
producers will commonly describe the morphology of their cultivars and will disclose if
they experienced any fox-tail traits in grow trials/testing.
Root zone health and soil or media pH can play a big role in fox-tailing. Cannabis
plants prefer a slightly acidic growing medium (6.2 – 6.8 during the veg stage for soil) as
this allows optimum nutrient uptake of all macro and micronutrients the plant needs. If
the pH balance gets skewed too acidic or too alkaline then this can cause nutrient lock
out which can cause excessive stress to the plant and may trigger fox-tailing.
One way to prevent fox-tailing is increasing airflow around the plants. This could
mean defoliation, adding fans to rooms, planting your cannabis in a spot outdoors that
gets plenty of air movement, etc. This will allow the leaves to have good gas exchange
around the stomata and can keep hot air from building up around the plant. Some
outdoor growers use cloth or some other material as a kind of shade for days of intense
heat/light and little wind.
Another way to prevent fox-tailing is to adjust your lighting if you suspect that was
the cause of the issue. Sometimes lights just need to be raised to be farther from the
plant so they don’t overheat, or even burn, exterior plant structures. Many grow lights,
especially LEDs, can have the power adjusted to decrease the intensity of the light
reaching the leaves and stalks to decrease the chance of overheating the plant.
An obvious way to avoid fox-tailing is to buy cultivars known to not have this
issue as it eliminates the high potential for this morphology to appear. Regardless of if
seed producers saw fox-tailing or not in their trial runs, fox tailing can still occur
occasionally in strains due to one or several of the reasons mentioned above
How bad is fox-tailing? It depends on when it occurs and the severity of the trait
in your grow. Often, fox-tailing occurs later in bloom after buds are already mostly
formed and have gained a good amount of weight. This means that a few fox-tails aren’t
going to really hurt your final yield or, in general, the potency of the final product.
However, if a strain begins and continues to fox-tail early in in its flowering stage then it
may not yield as well as it could have.
Ultimately a little fox-tailing isn’t really going to hurt anything in your grow nor will
it really affect your final yields unless it is very prevalent so it isn’t anything to be too
concerned about in general. Seeing signs of fox-tailing can be a good indicator for the
grower that something (heat, light, pH, root zone health, etc.) is off with their grow room
or grow area conditions and can be a non-fatal warning sign that certain parameters
may need to be adjusted to ensure robust plant health and high final yields.
Polyembrony:
Sometimes seeds will produce two taproots (radicles) when germinated. It can
seem very alien but is a natural, albeit rare, occurrence in cannabis seeds. If you
germinate a seed and get two radicles instead of one then you have a polyembryonic
seed.
As stated above, polyembryonic seeds have multiple embryos in a single seed
shell rather than the usual singular embryo. This means you get two plants for the price
of one seed! If you can separate the rots of each embryo you can pot them in separate
containers and grow two plants of a favored strain. Sometimes though the radicles get
tangled up together or the radicles emerged under the growing media and a grower
didn’t see until they had two seedlings emerging. This is still okay as the plants can
either be separated, trained away from one another, or simply left to fend for themselves
and the stronger of the two plants will out-compete the other.
Polyembryony in cannabis seeds is primarily caused by the spontaneous
cleavage of the zygote during its early development. This causes a single fertilized egg
into two or more cell masses, each capable of developing into a genetically identical
embryo.
Reasons for this phenomenon include:
-Zygotic Cleavage: The initial pro-embryo divides into multiple cell masses during its
earliest stages. This will ensure that the resulting embryos carry an identical
chromosomal blueprint from the parent cells.
-Environmental Stressors: Extreme temperature shifts, nutrients deficiencies, and/or
chemical exposure can cause emergency reproductive pathways to activate and induce
the formation of multiple embryos.
-Genetic Factors: Genetic mutations or variations in regulatory genes involved in
embryo development can lead to multiple embryo formation from a single zygote.
-Nucellar Embryony: A type of apomixis (the asexual development of a seed or embryo
without fertilization) where nucellar embryos from the nucellus tissue of the ovule are
formed without meiosis or sexual reproduction being involved at all. This type of
embryony will create identical genetic copies of the mother plant and thus will
essentially be “clones” of the mother plant but from seed.
Polyembryony is fascinating and not harmful to your plants in most cases which
makes it a very interesting mutation to see in person. Out of the hundreds of thousands
of seeds germinated thus far at Dirty Bird, we have only experienced this mutation twice
making it a very rare and very cool occurrence.
Check out more educational posts:
HAPPY GROWING!