Million Orchid Protocol - Fairchild Tropical Botanic Garden

Citizen Science: Fairchild’s Million Orchid Project
2015-2016 Information and Procedures
For more information, tutorials, and resources visit the Fairchild Challenge web pages:
http://www.fairchildgarden.org/education/the-fairchild-challenge
Fairchild’s Million Orchid Project
Fairchild Tropical Botanic Garden is propagating a million native orchid plants for
restoration into South Florida’s urban landscapes. The Micropropagation Laboratory at
Fairchild is generating large quantities of native orchid plants from seed, with the
assistance of students and volunteers from the local community. We are now
propagating eight species of of native orchids, including the easy-to-grow Florida
butterfly orchid (Encyclia tampensis). Our goal is to reestablish native orchids within
South Florida's public landscapes, around schools, on street trees, and in city parks.
The Million Orchid Project is unique in its scale, its exclusive focus on public
landscapes, and its involvement of the local community from the beginning.
South Florida was once an orchid paradise, with a rich flora of tropical orchids growing
naturally on the branches of every tree. In the late 1800s, as the Florida East Coast
Railroad extended southward, orchids were among the first natural resources to be
exploited. Flowering orchids were ripped from the trees and packed into railroad cars,
destined to be sold as disposable potted plants in northern flower shops. Orchid
populations dwindled rapidly, and now our iconic native orchids exist in such small
numbers that they have little hope of recovering on their own.
A few orchid species still persist in very low numbers in South Florida. Each orchid
bloom may yield a seed pod, which can contain more than a million seeds. The vast
majority of the tiny, dustlike seeds will never grow into a new plant. Orchid seeds are
dispersed by the wind, and their success depends on landing in a location with
extremely specific growing conditions. To grow successfully, they need to land on a
patch of tree bark with the proper species of symbiotic, microscopic fungus, an
exceedingly rare event.
Today, our region has countless suitable landscape trees for orchid reestablishment, in
schoolyards, roadways, and other public spaces. Within five years we expect to have
orchids in a wide variety of local urban settings, especially in the places where people
live, work, and learn.
At its core, the Million Orchid Project is a massive science experiment that allows us to
make important discoveries about how native orchids grow and reproduce. Additionally,
the science of the Million Orchid Project may help us develop more general strategies
for rescuing rare plants within a highly developed urban environment.
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Orchid propagation in the laboratory
In nature, most orchids depend on a symbiotic relationship with a microscopic fungus.
Orchid seeds lack the energy reserves that would allow them to germinate and grow on
their own, and therefore they need to absorb energy from the outside. Symbiotic fungi
can process nutrients from the environment and convert them into the carbohydrates
that trigger orchid seed germination and fuel seedling development.
The orchid-fungus symbiosis is a complex relationship that we are only beginning to
understand. It appears to depend on each species of orchid associating with a single
type of fungus. In the wild, the chances of an orchid seed connecting with the proper
species of fungus are extremely low. We estimate that fewer than one in ten million
orchid seeds ever develop.
In the laboratory, we are able to grow orchid seeds without symbiotic fungi. The
technique, called asymbiotic germination, involves embedding orchid seeds in a
carbohydrate-rich agar-based medium that mimics the mixture of chemicals that would
be supplied naturally by a fungus. The first experiments with asymbiotic germination
were done in the 1920s, and the technique continues to be improved and optimized for
each type of orchid. It is now possible to have nearly 100% seed germination using
asymbiotic techniques. Today, the orchid industry uses asymbiotic germination to
produce massive numbers of plants for sale worldwide.
The agar-based medium used to culture orchids can also support the growth of many
kinds of fungi and bacteria. When the medium becomes contaminated, it can be overrun
by fungi and bacteria that grow and absorb nutrients more rapidly than the orchid
seedlings. For this reason, it is important to keep the orchid medium sterile and prevent
exposure to the fungal spores and bacteria that are constantly circulating in the air.
Prior to use, we sterilize orchid medium, containers, and propagation tools under the
intense heat and pressure of an autoclave. Orchid seeds and seedlings are manipulated
with sterile tools within a laminar flow hood, a sterile workspace that continuously
scrubs the air of any microbes. Once the orchids are planted, containers are sealed and
placed on shelves outside the laminar flow hood.
As orchid seedlings grow, they consume the supply of nutrients in the medium. Every
two to six months, seedlings need to be transplanted onto fresh medium in new
containers, all within the sterile environment of a laminar flow hood. Seedlings are
transplanted two to four times, until they are well developed and able to produce their
own energy through photosynthesis. Depending on the orchid species, seedlings
usually live inside sterile containers for nine to 18 months after germination.
In sterile containers, orchids are bathed in constant humidity and nutrient-rich growth
medium, and they have complete protection from pests and diseases. Those conditions
disappear when the orchids are removed from the containers. The first shock to the
plants is an immediate exposure to drying conditions, but within days they may also
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begin to suffer from the lower availability of nutrients and exposure to microbes. The
care seedlings receive during those first days out of the containers is critical to their
success.
After we remove orchids from sterile containers, we usually keep them indoors on
shelves or in a greenhouse for weeks or months. We use a time-release fertilizer to
compensate for the lack of nutrient-rich medium. As the plants become larger and more
robust, they are moved outdoors and attached to the branches of trees.
Encyclia tampensis, the Florida butterfly orchid
Encyclia tampensis is the most abundant of our native orchids, with small populations
surviving across a range of environments. It is found from the Florida Keys to coastal
areas north of Orlando, and also occurs in the Bahamas. E. tampensis is an epiphyte,
growing on the branches of several tree species.
For the Million Orchid Project, we are focusing on E. tampensis as one of the species
most likely to thrive in our urban landscapes. Once we reintroduce E. tampensis
throughout South Florida, we hope it will be able to persist and reproduce on its own.
We have grown E. tampensis in the laboratory, and have successfully established our
lab-grown plants on trees in the community. However, we have had a low success rate
when acclimatizing the seedlings after removing them from sterile containers. As we
begin growing larger numbers of orchids, we are interested in optimizing the protocols
for growing healthy seedlings that can survive outside sterile culture.
Encyclia tampensis growing naturally on an oak tree at Fairchild.
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The Challenge
Your challenge is to help us identify optimal conditions for growing Encyclia tampensis
during specific stages of production. We are trying to determine which type of medium
works best for the final stage of sterile culture, and which fertilizer conditions are best
for acclimatizing seedlings afterward.
You will be judged on the basis of how closely you follow the experimental protocol, the
quality of the data you submit (on time and properly formatted), and whether your
tweets and comments reflect an understanding of the experiments and the broader
issues they are addressing. Points will also be awarded for any analysis you are able to
do comparing the three types of medium, in terms of plant growth and development, at
any stage of the experiment. You may refer to the evaluation sheet, which will be
available on the Fairchild Challenge web pages.
At the end of the school year, you will have the opportunity to plant the orchids on trees
around your school.
Materials distributed on January 16, 2016
For all schools:
12 containers of year-old Encyclia tampensis seedlings in 3 types of medium
Bag of perlite (lightweight potting medium derived from volcanic rock)
Bag of fertilizer pellets (Nutricote 18-6-8 or Florikote 16-5-11)
Fairchild Mini Botany Lab sign
Felt square
Spray bottle
Tube of Liquid Nails glue
Lighting equipment for schools with fluorescent lights on the top shelf:
4 fluorescent fixtures
Power cord
3 linking cables for connecting the fixtures to one another
Zip ties for attaching fixtures to shelves
Lighting equipment for schools with LED lights on the top shelf:
Power supply
Panel of LED strips
Zip ties for connecting the panel to shelves
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Orchid medium
Asymbiotic culture requires a nutrient-rich medium that provides energy to the
developing orchids. We use a standard, commercially available medium that works for
many different types of orchids. Orchid growers have found that they can influence the
health and structure of developing plants by supplementing the medium with various
carbohydrate mixtures. Extracts of banana or potato have been found to have a positive
effect on root development for many kinds of orchids. We are including both as separate
experimental trials in this Challenge, along with a standard medium without
supplements. We use food coloring to identify the three different medium recipes:
Blue: Standard medium (25.31 g/l O139 + 2.50 g/l G434)
Green: Medium with potato powder (25.31 g/l O139 + 2.75 g/l G434 + 10 g/l P692)
Red:
Medium with banana powder (25.31 g/l O139 + 3.00 g/l G434 + 10 g/l B852)
Orchid medium components, all from PhytoTechnologies (phytotechlab.com):
O139=Orchid Maintenance/Replate Medium Without Charcoal and Agar; G434=Gellan
Gum (gelling agent); P692=Potato powder; B852=Banana powder.
Fertilizer
We are experimenting with two different formulations of time release fertilizer that have
been used in the orchid industry. Both are produced by Florikan ESA (florikan.com):
Nutricote 18-6-8 and Florikote 16-5-11. We have assigned these formulations to schools
randomly, and will compare results across schools.
Calendar
Week 1-9 (1/18-3/18): Grow orchids in sterile containers on the top shelf of the Mini
Botany Lab. Every week, rotate, check for contamination, and estimate whether each
container has a greater amount of leaf or root tissue. Send a scientifically relevant tweet
and update the Google Sheet weekly.
Week 11-18 (3/28-5/20): Grow orchids in non-sterile containers, first on the top shelf of
the Mini Botany Lab, and then in the growth chamber on the bottom shelf for the final
week before planting outdoors. Mist plants daily (when school is in session). Monitor
plant health and rotate containers weekly. Send a scientifically relevant tweet and
update the Google Sheet weekly. The Challenge is due April 20.
Week 19-21 (5/23-6/9): Plant orchids on trees around the school. Tweet photos and
provide planting data on the Google Sheet.
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Procedures
1. Transporting and handling orchids in sterile containers
You are receiving plastic containers with orchids in sterile culture. Within the containers,
there is a gelatinous medium that will be disrupted if the container is tipped or shaken.
Be sure to keep the container as level as possible, and avoid any sharp movement or
shaking. Be careful to keep the seal around the lid intact so the cultures are not
exposed to contaminants in the air.
2. Installing lights on the top shelf of the Mini Botany Lab
Some schools are receiving four fluorescent light fixtures. Others are receiving a panel
of ten red/blue LED strips. We will be comparing growth of orchids between schools
with LED lights and schools with fluorescent lights. For both types of lights, one unit is
connected to the power source, and the individual units are daisy-chained together.
If you receive fluorescent bulbs, attach the fixtures to the top shelf with zip ties. Space
them as evenly as possible. Use the power cord to connect one of the fixtures to the
timer, and use linkers to connect the rest of the fixtures in a chain.
If you receive a panel of LED strips, use zip ties to connect the corners of the panel to
the top shelf. Plug the power supply into one of the free connectors. Be sure all the
individual strips are connected to one another in a chain. Plug in the power supply to the
timer.
Set the timer to be on for 12 hours / off for 12 hours.
3. Maintaining orchids in sterile containers
Place the 12 orchid containers on the top shelf of your Mini Botany Lab. Distribute the
three colors of medium evenly, and rotate positions weekly as shown:
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2
3
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12 1
2
3
11 12 1
2
10 11 12 1
5
6
7
8
4
5
6
7
3
4
5
6
2
3
4
5
9 10 11 12
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9 10 11
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9 10
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Week 1
Week 3
Week 2
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Week 4
Check the orchids weekly for signs of contamination, which will appear as white, gray, or
sometimes colorful blotches on the surface of the medium. When in doubt, observe the
cultures for a few days to see if the blotches grow larger. If you are sure a culture is
contaminated, discard it.
Orchid culture contaminated with a fungus.
There may be a black substance adhering to the roots of some orchids, or mixed in with
the medium. That is probably not a contaminant, but is more likely to be a remnant of
the charcoal included in the medium during an earlier stage of growth.
The three experimental formulations of medium may promote different relative rates of
leaf and root growth. Therefore, the ratio of leaf tissue to root tissue may change while
the orchids are in the container. Each week you should record the leaf vs. root length
and any observations of general plant health.
4. Removing orchids from sterile containers
The most difficult stage in orchid propagation is the transition from sterile containers to
the outside world. Handle the orchids with care, wash, measure, and weigh them gently,
and be prepared to observe them closely for the next few weeks.
You will need a sink, paper towels, scales, rulers, and a notebook to keep track of your
measurements. A colander or strainer is helpful, but is not essential. Have your perlite,
fertilizer, and spray bottle on-hand.
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Peel away the plastic seal and remove the lid from the container. You will be keeping
the lid and the container. Gently lift the orchids out of the medium and rinse the medium
away. Use a colander if possible to avoid losing orchids down the drain.
Once all traces of medium are gone, gently pat the orchids dry with paper towels. The
seedlings may still be damp, but should not be dripping wet. Set the orchids aside on a
paper towel, keeping them together so they can be returned to the same container.
Wash the container thoroughly to remove all traces of medium. Add perlite to the
container, to an even depth of about 3 cm. Add 1 g of fertilizer granules to each
container, distributing the granules as evenly as possible.
Weigh all the orchids from each container together, and record the total weight of the
orchids for each container.
For each individual plant, measure the longest leaf and longest root. In containers that
have more than 12 plants, choose the 12 largest plants to measure. Calculate and
record the average longest leaf and longest root per container.
Place the orchid plants back into the container, on the surface of the perlite, gently
pressing some of the roots just below the surface to help anchor the plants upright.
Use the spray bottle to mist the orchids five times. Gently pour off any excess water.
Return the lid to the container, but do not close the lid completely. Keep the lid slightly
open to allow some air exchange while keeping a humid environment in the container.
Orchid seedlings in a non-sterile container with perlite and fertilizer, with the lid open slightly.
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5. Maintaining orchids in non-sterile medium
Return the orchid containers to the top shelf. Mist the plants every weekday, just
enough to moisten them. Gently pour off any excess water. Collect data on plant health
weekly.
Continue to rotate container positions weekly as before.
6. Preparing seedlings for planting outdoors
The plants should be allowed to adjust to a higher intensity of light one week before
they are planted outdoors. For that purpose, you will use the growth chamber on the
bottom shelf, with the more intense LED lighting fixture.
Place black felt in the bottom of the tray, and keep the felt moist. That will maintain a
high level of humidity in the growth chamber. Remove the lids from the orchid
containers, place the containers in the growth chamber, and cover the chamber with the
clear corrugated plastic.
Connect the LED lighting fixture to the timer, set to be on for 12 hours / off for 12 hours.
Every weekday, check the moisture of the felt in the growth chamber, and mist the
plants just enough to moisten them. Gently pour off any excess water.
7. Planting orchids outdoors
Encyclia tampensis is an epiphytic orchid that grows best on horizontal branches of
hardwood trees. Live oaks (Quercus virginiana) are ideal, because the tree architecture
allows some sunlight to reach the branches. Mature oak bark has deep fissures, well
suited to rooting orchids and retaining moisture. Mahogany trees, buttonwoods, and
slash pines are other good candidates. It would be worthwhile to experiment with other
native and exotic trees. The final weeks of school are ideal for planting orchids, because
they are within the start of the warm, rainy season in South Florida.
Select horizontal limbs that have good exposure to light. It is best to choose branches
that are visible, but not not reachable from the ground. Use a stepladder if possible.
Apply large drops (1-2 cm in diameter) of Liquid Nails glue directly to the bark of the
tree, spaced at least 10 cm apart. Allow the glue to harden for 15 to 30 minutes, until it
has the consistency of sticky clay.
Press the pseudobulb (base of leaves, above roots) into the drop of glue, allowing the
roots to hang below the glue and contact the bark. Avoid embedding roots in the glue.
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Top left: Encyclia tampensis with pseudobulb (leaf bases) embedded in Liquid Nails glue and attached to
an oak limb. Top right: A student planting E. tampensis on an oak. Bottom: E. tampensis eight months
after planting, with new root growth marked.
Most small to medium-size orchid seedlings will adhere without any further method of
attachment. Within one growing season, the orchid roots should grow and fully adhere
to the bark on their own. Watering is usually not necessary.
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Entering Data
You will receive an email with a link to the Google Sheet where you will enter all data
and comments related to this Challenge. Please update the data sheet at least once a
week so we can track your progress.
Using Twitter
At least once a week, send updates to the Challenge team (and the rest of the world)
via Twitter. Include scientifically relevant observations, data, or photos. All tweets should
include the following:
#MillionOrchidProject
@FairchdChallnge
Be sure to enter your Twitter username on your Google Sheet so we know how to find
your tweets.
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