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Screening
orchids for production seems to be a necessary and ongoing
process. There are a number of factors that determine whether
an orchid variety is going to be viable as a pot plant or
cut flower for your nursery. The first consideration is whether
you can grow it in your location. Does it grow reasonably
well in terms of producing attractive foliage? Is it easy
to bloom and blooms repeatedly each year or several times
a year? When it flowers does your market prefer it to others?
Do the flowers have a long enough shelf life? Does the plant
handle shipping well? There seems to be a never-ending array
of concerns that are important to consider when selecting
orchid plants to grow.
Because we grow a fairly wide range of orchids we find ourselves
paying particular attention to certain generas to make sure
that primarily we are able to grow the plants reasonably well.
We also try new generas and varieties in small quantities
to determine if it is worth trying them on a larger scale.
We find ourselves constantly screening orchids that do well
not only in our nursery in general but also in particular
areas of our greenhouses. Variation in light or air circulation
seems to play a fairly large role in terms of what varieties
do well. Once we map out our greenhouses we then screen for
more similar types to grow in those areas.
Over the years experience has taught us that screening begins
prior to pollination and continues through adulthood. Screening
for viable parents takes a number of years. One very effective
area of screening is in the laboratory. Not all seedlings
grow alike. The lesson experience has taught us is, that if
plants are not growing vigorously in the lab, then there is
a high probability that this will continue through adulthood.
No matter how great a set of parents may seem, there are unknown
genetic consequences of each pairing, and the early stages
seem to be the best indicator of their progeny's merit. Yes,
it may seem horrible, but we do discard thousands and thousands
of orchids before they even get a chance at life. If a batch
of orchids is showing signs of some abnormality or general
lack of vigor we simply throw them away, no matter how wonderful
we envisioned the cross to be. On a positive note we do look
for extra vigorous seedlings and will tend to produce a greater
number of flasks of these. Although nothing in orchids seems
to be a guarantee, our aim is really to increase the probability
and proportion of superior seedlings by screening the seedlings
during their first year of development.
Screening also continues after seedlings are removed from
flask. Here we are looking for plants that do extremely well
in the open environment. This continues through their adulthood
and the final screening comes when we select plants for future
generations. Many growers have asked us to remake hybrids
much like the University of Hawaii cultivars. Yes, we are
working toward developing similar reliability of the University
of Hawaii cultivars, but we also find that we need to fulfill
an even greater need: The need for a continued flow of new
varieties that are improvements over the previous years.
So how do we screen new hybrids if we are constantly looking
for improvements? Ultimately it seems that the parents and
their ability to produce reliable progeny is a vital consideration
in new hybrids. Over the years we have found that particular
parents paired with particular types will produce exceptional
progeny. Also particular parents are well suited to be crossed
to particular groups. For example Den. Jaquelyn Thomas (4N)
produces excellent hybrids when crossed to the Dendrobium
phalaenthe group (4N). This group we termed 'Inter-Den-Phal'
because it is somewhere in between the two. This particular
pairing produces vigorous plants that tend to bloom early
with fairly large flowers and blooms many times a year. The
parent of Dendrobium phalaenthe needs a good amount of scrutiny
but once it is determined that it will produce exceptional
progeny then other possible combinations can yield a wide
range of colors with similar success.
Having full control over what gets propagated in the lab plays
a key role in producing quality seedlings. Having experience
with each parent being used and an understanding of what types
of combinations will have a high probability of success helps
to minimize the discarding of seedlings in the flask stage.
But what about screening for plants if you are just beginning
to raise orchids? Looking back to our beginnings I think first
and foremost it is important to raise healthy, virus free
plants. There just doesn't seem to be an efficacious way to
economically remove virus in orchids and if you have a few
virused plants they can easily spread it to others. The next
step is to trial plants and see what types grow best in your
area. Over the years we have adapted our greenhouses to raise
a number of different generas that we previously couldn't
grow successfully. So it's really like moving in two directions
at once.
Then as you get more experienced raising more groups you can
try more and more types. At some point though it may not be
economical to raise particular groups that require temperatures
that have a marked difference than your particular temperature
ranges. And most times it's not really worth the expense of
trying.
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