Million Orchid Protocol
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! 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. !2 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 !3 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. !4 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 !5 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.