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Propagating By Seeds
Lilies in general, either species or
cultivars are self sterile. This means they will not produce seeds if their
own pollen from the anthers is placed on the stigma.
Because of this cross pollination is the only way seeds can be produced.
When you think about it, nature is guaranteeing that each seed will have two
different sets of Chromosomes and sexual cloning cannot occur.
Each seed will have slight variations from others and minute genetic
characteristics for good or bad are introduced into the gene pool. One of
these random variations may create a yellow or red flower from orange
parents, another variation may make a group of specimens more resistant to
virus or fungal infections. Over time these minute variations might create a
whole new species.
A great advantage of raising species lilies
especially and cultivars from seeds is that if a group of lilies have a
virus this does not pass to the seeds. Another advantage is since a single
pod can have between 20-100 seeds it would not take many pods
to create a huge population of any one variety. This makes it relatives
inexpensive to produce commercial stock or slow dividing wild species. Some
species are prohibited from being collected from wild stock due to declining
populations and can only be purchased as seeds.
To grow lilies from seeds does not take allot
of room or money. You do not have to be botanist with a PHD. Anyone with a
sense of adventure can hybridize in a relatively small space. I know from my
own experience that it is a very exciting time when I see flower buds
developing for the first time on some of my seedlings and when they open for
the first time its like getting a Birthday Gift. Not all are going to be
wonders to the lily world, but you do have the knowledge, that you created
this hybrid and no other plant will be genetically identical, it will be one
of a kind until it multiplies and makes more of itself. But, the best thing
of all this is just maybe you will create a lily so phenomenal that it will
take the Lily world by storm. That's what happened to the creator of the
Oriental Lily "Stargazer". The parentage of Stargazer
is unknown, but it is one of the biggest selling Lilies commercially in the
world.
Before you can get seeds you have to cross
pollinate two different plants. They can be the same species of lilies, two
different species or different cultivars (Cultivated Varieties).
Crossing two different species or cultivars is know as Hybridization,
the offspring are hybrids of two different type of lilies. All the cultivars
produced are from different parent types. Crossing two parents of the same
species does not give you a hybrid as the seeds will breed true to form with
minor differences. These differences if great enough from the original
species description are normally called Varieties as opposed
to hybrids.
There are basically two types of hybridizers.
First the serious hybridizer that is looking to create a very specific
characteristic in a new hybrid. They will keep well documented notes on
their crossings and tag each seed pod with a code that they understand to
keep their records straight. Then there is the second type which normally
every novice hybridizer fall into (including myself). They just take pollen
from their favourite lilies and go around like Johnny Appleseed spreading
pollen to any other plant that catches their eye. Not really looking for a
specific characteristic but just seeing what might happen to come up. The
thrill of the potential new colourations is what makes it exciting for them.
In time many out grow their "Playing" stage and get into more serious
hybridization when their experience grows.
Choosing Parents to Cross
Before you can have seeds you must cross
pollinate two different plants. It is important to understand that some
plants just will not cross pollinate and produce viable offspring because
they are just too different genetically. Orienpet varieties
are the result of crossing Oriental Lilies with Trumpet
Lilies. However the seeds produced will not germinate without
intervention from humans and a sterile laboratory. So if you want to create
your own lilies it is easier to stick within varieties when cross
pollinating. As you get more advances in your knowledge you can try more
difficult cross-variation hybrids.
So once you have decided which two plants you
wish to cross you must decide which will be the mother plant and which will
be the father plant. Each halve will pass on certain of its own
characteristics more dominantly that the other. Switching the two around
will produce a different look than the other cross.
Producing seeds
There are two ways to produce seeds. the
first is by using natural pollinators, bees, birds, wind. When using this
method and leaving chance to the wind sort of speaking, there may be pollen
from more than one variety at the same time in the flower stigma. The
outcome of such natural pollination is going to be totally random. You may
end up with any number of variations in the same set of seedlings.
The other method is deliberate artificial
pollination. This means the hybridizer crosses plants of his/her choice and
takes precautions to prevent random stray pollen from contaminating their
efforts.
When a hybridizer chooses his two potential
parents they usually have characteristics that when combined will hopefully
produce the lily pictured in the hybridizers mind. It might be a completed
picture or an intermediate step to another crossing in mind. A hobby
hybridizer has allot of advantages over a commercial hybridizer in that they
can have a greater range of possible outcomes from a cross. There is no
pressure to make a commercially viable plant to make profits from their
sale.
The actual mechanics of hybridizing is quite
simple, male pollen from the Anthers must be applied to the female
Stigma.
Pretty
simple. But there are various steps to be done before this can happen.
The plant that is to be pollinated is called
the Pod Parent, the plant whose pollen is to be used is called
the Pollen Parent. First the Anthers should be
removed from the Pod parent. This should be done before they
get ripe and release their own pollen. If its own pollen gets on the
Stigma it will not actually pollinate itself but may block the
Pollen parents pollen from fertilizing the Pod
parent. The Anthers can be removed by hand or tweezers
The Stigma of the Pod
parent will ooze a clear sticky liquid when it is receptive to receiving
pollen. This is the time to apply the pollen from the Pollen parent.
The simplest way to apply the pollen is to take the Anther and
spread the pollen evenly on the three lobed Stigma.
If the lilies bloom at different times it is
possible to store pollen to be applied later. To do this take the
Anthers just before they have split open, place them in a plastic
container with the lid off and leave them in a warm dry place until the
Anthers have split open and dried out. Label the lid of the
container right away before you forget which plant it comes from. When the
Anther is dry and the pollen is free place the closed plastic
container in a regular refrigerator until the Pod parent
become receptive. Pollen can be stored for months in this manner, it can
also be frozen for much longer periods. Old film containers work well for
this type of storage.
If using stored pollen to pollinate a
Pod parent a Q-Tip works well as it is disposable.
Once the Pod parent has been pollinated cover the Stigma
with a cap made from folded aluminum foil. Shaping over the
eraser end of a pencil usually give the proper size and shape for most
lilies. The cap protects the Stigma from any stray pollen that
might touch it and also damage from rain, chemicals or insects.
Label the cross clearly by tying a tag to the
flower stem leading to that cross. When labeling mark down the Pod
or Seed parent first and then the Pollen parent,
for example, 'Monte Negro' x 'Night Flyer'. Also put on the
date. You can also use a code number as well like Jn001/06
meaning this is the first cross you did in June 2006. This can be used in a
notebook or a computer diary as a record column to keep track of the
parentage of your seedlings.
From this point on your job is done and you
can sit back and relax, let nature do what it is going to do. Either
fertilization will occur and the pods will start to grow or it did not
happen and they won't.
Collecting Seeds
If your crossing efforts were successful the
lily ovary will start to enlarge as the seeds inside start to grow.
Each variety of lily has a different size and shape of seed pod, but all
will look swollen if the fertilization has taken place. If it has not the
seed pod will look small and shriveled. The maturing of the seeds will take
six to eight weeks before they begin to ripen. The ripe seed pod turns brown
and will start to split along three lines getting ready to
release
the seeds it contains. It is best to collect the seed pods only in dry
weather. If this is not possible due to a wet late summer or early fall or
if the seeds are from late blooming varieties and there is not enough time
leave the seed pods to fully ripen before frost. The flower stem can be cut
while green or partially green and hung upside down in a warm dry place
until the seed pods are fully ripened. Keep a close eye on them as they get
ripe. If you have more than one cross on the same flower stem and the pods
split open dropping their seeds, chances are they will get some overlap and
seeds will be mixed up. If you have room to separate each flower cross with
a white sheet of paper under them, with the cross information it will make
your life easier. Another method that can be used if you do not have the
time to check your hanging seed pods regularly is to put a square of fine
mesh over the pod and secure with an elastic. This way of the pods dry
before you can get to them the seeds will fall into the mesh net and you
won't lose them.

The seeds should be removed from the pod when
they are dry and allowed to fully dry before planting. This will reduce the
chances of Botrytis forming. If is a good idea at this point now that the
seeds are dry to check for the embryo with in the seed.
To check for the embryo you can take an individual seed in a pair of forceps
and hold it to a strong light. The embryo will look like a line in the
middle of the seed. You can sort of see it in my photograph. Another method
to check is to place the seeds on a white piece of paper or frosted glass
and use a strong light source below. Some seeds have darker pigments so
seeing the embryo might be difficult.
If you have trouble seeing the embryo it is
safe to bet that if the seed is plump there is more than likely a viable
embryo inside. If your planning to sow the seeds fairly soon you can store
them in the refrigerator, in well sealed containers. Seeds can be survive
for 35 or more years if they are stored in below freezing temperatures. If
your going to store them for any length of time, label everything carefully.
It would be next to impossible to identify crosses just by looking at the
seeds.
Sowing Seeds
There are a number of ways seeds can be sown
to get them to germinate. But no matter which method you use there are a
couple of basic necessities that the seeds need in order to germinate. They
are moisture, warmth and air. With these three necessities met, healthy
seeds should have no problems getting started. Seeds can be started directly
into trays of a seedling mix and covered with about .25in (6mm) of
vermiculite, sand or grit. Space the seeds out to allow air circulation and
prevent Dampin Off, which is a fungus disease that can attack seedlings.
Spray the trays with water and place them in a warm area. If you have the
clear plastic lids used for seedling trays you can place them over to slow
down water evaporation. Moisture is extremely important to get the seeds to
germinate and start growing. If the medium dries out before they will more
than likely die very quickly.

Another method that I used to germinate my
seedlings is I dampen some vermiculite and put some in a Ziplock bag. Then I
place the seeds inside the bag and put them under my growing lights. The
warmth from the florescent fixtures raises the internal bag temperature and
the seedling seem to start germinating in a week or so. Some take longer.
With this method I had very few seeds that did not germinate. Once the seeds
gave germinated they have to be replanted into trays one at a time. It is
very time consuming and if you have allot of seedlings it might be easier to
use the first mentioned method so you do not have to transplant. I just
found I had a greater success rate using the Ziplock method. You will have
to experiment and figure out which method works for you depending on over
all time you have to spend with your crosses.
Germination Methods
Lilies have two types of germination methods
depending on the variety. Epigeal or 'Above Ground'
and Hypogeal or 'Below Ground'. These two
methods are further subdivided into two sub-methods, Immediate
and Delayed. For the most part the categories most lilies fall
into are Immediate Epigeal and Delayed Hypogeal. It is important to know
which category your seeds fall into, as the handling of them for germination
is different.
In Epigeal germination The seeds sprout very
quickly after it has been exposed to moisture and warmth. A
long
slender Cotyledon emerges, quite often carrying the seed coat at the tip.
The cotyledon is not a true leaf but a temporary pseudo-leaf to that does
contain Chlorophyll to start manufacturing food in order to initiate the
growth of the underground bulb. From there the true leaves will form. As the
bulb grows more leaves will be formed which in turn makes more food to be
stored in the bulb. Asiatics and Trumpets use
Epigeal germination methods.
Seeds can be sown outside if you have large
quantities of crosses. The seed beds must have excellent drainage and a high
fertility level to maximize bulb growth in the first season. Outdoor
germination is usually done in the large commercial hybridizers as the soil
is usually sterilized chemically to control pests and diseases. But if you
wish to do germinate yours outside the beds are prepared in the Spring for
Epigeal germinated seeds. The beds must never be allowed to dry out during
the germination stage. Fertilizing should be a low nitrogen fertilizer to
allow maximum nutrients for the formation of roots and bulb. Slow release
fertilizer when the beds are prepared and later in July should be enough for
the season. Keep an eye open for Botrytis and spray to control it if
necessary. The beds must be free of weeds at all times as they are competing
for nutrients that your growing seedlings should be using. Insects must also
be controlled especially Aphids. It is better to use a systemic granular
insecticide as spraying may damage tender new leaves.
For greenhouse operations, beds can be right
at ground level or trays of soil can be used or raised beds that hold soil.
The soil once again must have good drainage capabilities. Everything must be
sterilized just as if you were planting in outdoor beds.
To germinate seedlings in containers and a
wide variety of containers and media are available.
Soilless
seedling mix is a good media to use as it is light and airy. Flats or pots
can be used to hold the mix depending on your needs. The flats or pots can
then be put either into a greenhouse, coldframe or under artificial lights
around February. What I use to germinate my seedling is damp vermiculite in
ziplock bags. This method has worked very successfully for me with either
Epigeal or Hypogeal germination.

These pictures were taken in 2004 and shows
some of my seedlings under fluorescent lights. I use regular commercial 4
tube instant on florescent fixtures. For lights they are a mixture of two
cool white and two warm white tubes that can be bought at any hardware
store. The lights were kept no higher than 4 inches above the top of the
seedlings.
Delayed Epigeal is not a method
of germination used by very many Lilies. Some species seem to need a cold
period before germinating.
Hypogeal germination is a
pattern where the seeds germinate slowly underground. Instead of pushing out
a Cotyledon right away it stays inside the seed coat
underground. The seed will put all its energy into producing a tiny bulb.
Once the bulblet forms it needs to go through a cold period for about three
months. I put mine in the refrigerator in marked Ziplock bags. You can
actually see the bulblet and root mixed in with the vermiculite.
Oriental lilies use Delayed Hypogeal
germination. Once the seeds are collected and dried they can be sown in the
plastic storage bags with either vermiculite, peat, or a mixture of the two.
The moisture level of the medium is very important, it must be damp and not
wet. If you can squeeze water out of the medium then it is too wet. The
roots require oxygen and to much water will drown the newly growing roots.
Do not completely close off the bags so air can come enter. Make sure you
clearly label each bag.
The bags are then places in an incubation
area at 60-70F (15C/21C) for three to four months. During this time the
seeds will germinate, grow a root and start forming the bulblet. The
Cotyledon does not form yet. Once the bulbs and roots are formed the
bags are moved into a cooling area at approximately 50F (10C) for about
three weeks. After that they are placed in cold storage for a minimum of 12
weeks at 34F (1C). This cold period is called the Vernalization
period.
After the Veralization Period
is over you can plant them outside when the soil temperatures and light
requirements can be met for immediate growth. The bulblets should produce
true leaves in about a week after planting. You can also plant them inside
under lights in the same method as Epigeal seeds are planted.
Immediate Hypogeal germination
is used only by a few species of lilies. L.brownii and
L.dauricum show this type of germination regularly. They can be sown
at the same time as Epigeal germinators.
Embryo Rescue
There are times when two very
different varieties of lilies get cross pollinated and seeds may form.
However due to genetic differences between the two plants there is an
incompatibility between the the embryo, which contains a set of chromosomes
from both parents and the endosperm or food source within the
cell, which only has chromosomes from the mother plant. This incompatibility
often leads to the disintegration of the endosperm and
subsequent death of the embryo.
If the embryo can be removed from the seed
before this takes place it can be grown in a test tube in a similar way as
tissue culture is done. The advance in technology to be able to do this has
lead to the development of the Orientpet
(Oriental/Trumpet) and Asiapet (Asiatic/Trumpet)
hybrids that are all the rage in the Lily world.
As to when the embryos should be "rescued"
depends on the cross. Some abort just before the pod would normally open.
Others are shortly after pollination. Some experimentation maybe necessary.
You may have to no multiples of the same cross and open them at different
times to see what is happening in the seed pod.
Embryo culture can be done by the home
hybridizer and supplies are available. The first thing you will need is a
clean working area that is comfortable to work at since this is not a
quickly done process. Then a glass topped box of some sort to provide a
sterile space to work in. You may be able to adapt an over turned aquarium
with one side or partial side glass removed to allow access tot he enclosed
space. Sterilize the inside of the box with alcohol or bleach. You might be
able to install an ultraviolet lamp inside the box. Ultraviolet light is a
germicide and is used to sterilize a work area. Your test tubes which will
have your medium already inside need to be sterilized in a pressure cooker
at 15psi for 20 minutes.
Once all that is done, you have to begin
removing the live embryos from their seed case. This is done by cutting the
seed case parallel to the the embryo as close as you can to the embryo. Then
lifting one half of the seed case off and using a pair of fine forceps or a
knife blade to lift the embryo and put it into the test tube of nutrient
solution. Immediately cover the test tube and place it in a standing rack.
Do not forget to label them before going on to the next one.
The embryos can be put into natural or
artificial light and if they are not contaminated they should start growing
quickly. Keep a very close watch on your test tubes as contamination may not
show up right away. If you do see contamination, you can try to pull the
embryo out of the test tube, re-sterilize it and put it into another test
tube, but this quite often does not work and the embryo is lost.
The key to all this is to keep your area
sterile as possible. Wear surgical gloves that can be bought through
Pharmacies or Medical Supply places. Keep your instruments sterile with a
10% bleach solution and distilled water. Distilled water is just condensed
steam, meaning it is H20 and nothing else. Tap water is full of chemicals,
algae and microscopic life. Rotate your blades and forceps after every
rescue and put the used ones to soak in the bleach solution.
If you are successful in keeping the tubes
from becoming contaminated, your embryo will start to turn green as
chlorophyll is produced in about a week. Then roots and leaves will start to
form to continue feeding the growing plant. After about 6-12 weeks the
little plantlets can be removed from the test tube by something like a large
crochet hook or similar tool. All medium that is clinging to the roots is
washed off gently with running water. At this time is it good to soak the
seedling in a liquid fungicide at its weakest strength. The soil they are to
be transferred to should be very light, a pre-made seedling mix can be found
at garden centers or you can make your own mix. The internet has great
resources for seedling mix recipes. The soil it is to be planted in should
be pasteurized.
To pasteurize place the soil in a seedling
tray or backing dish to a depth of no more than 4 inches. Do not pack it
down. Moisten it if it is not already moist. Do not over wet it. Place a
thermometer into the center of the pan but do not allow it to touch the
bottom of the tray. Place the tray in the oven at approximately 200F.
Maintain the soil temperature to 160F for 30 minutes. Allow to cool before
using.
Once the plantlets are in the soil it is
important to keep them misted and evenly moist as they adjust to the less
humid environment outside of the test tube. They will then be placed in a
warm environment with temperatures steady at 50-70F (10-21C) in good light
for six to eight weeks. This will give them time to grow a good rooting
system before they go into their cooling phase. The cooling phase lasts
about 12 weeks at a temperature of 38F(3C). Then they can be planted in
their growing site where they will continue growing until they flower in a
season or two.
This gives you a general idea on how Embryo
Rescue is done. More detailed information can be found on the internet for
those who wish to make the attempt. Just remember not every type of cross
can be made using Embryo Rescue techniques.
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