‘Greenhouse on a chip’ tests how plants will grow
Let’s say plant scientists want to develop new lines of corn that will better tolerate long stretches of hot, dry weather.
How can they precisely assess the performance of those new plants in different environmental conditions? Field tests can provide some answers. Greenhouse tests can provide some more. But how can plant scientists get a true picture of a plant’s growth and traits under a wide variety of controlled environmental conditions?
That job has been too big and too precise for most laboratories. There are a few labs around the world that can do the work, but the studies are expensive, limited and require time and labor. There hasn’t been an accessible test instrument with enough scale, flexibility, and resolution to produce all the data scientists need, says Liang Dong, an Iowa State University associate professor of electrical and computer engineering.
His idea is to develop a greenhouse on a chip—an instrument that incorporates miniature greenhouses, microfluidic technologies that precisely control growing conditions, and big data tools that help analyze plant information.
He calls his instrument a “transformative leap” in the study of plant phenotypes—the look, size, color, development, and other observable traits of plants.
“The instrumentation will make breakthroughs toward solving grand-challenging, large-scale problems in the field of phenomics,” Dong says. “We are building resources to benefit plant biology researchers and hopefully the new instrumentation will create a paradigm shift in the plant phenomics area by placing powerful data analysis capability in the hands of researchers.”
The research project has already produced a technical paper published in the journal Lab on a Chip.
To date, Dong and his research team have been building the necessary components for a phenotyping instrument. Now they’re working to integrate the parts and pieces into a complete, flexible system that can handle a variety of research projects.
“We’re building a toolkit that people can assemble and use to meet their needs,” Dong says. “We originally thought this would look at seeds growing in a cube. But now this can be scaled-up, depending on the growth stage researchers want to study. If it’s a plant’s first 10 days, we can make parts of the instrument smaller. If it’s four weeks, we make them bigger.”
Here’s how the tiny greenhouses will work
Dong and his team will build miniature greenhouses that precisely control light intensity, humidity, temperature, carbon dioxide, chemicals, and even pathogens. Plant scientists will fill the miniature greenhouses with clear, vertical, and disposable chips containing seeds that will grow into seedlings.
Hundreds of the chips-in-mini-greenhouses can grow thousands of plants at the same time, each greenhouse providing different environmental conditions. Dong’s current goal is to get 128 of the growth chambers working simultaneously and independently.
As the plants within all those chambers grow, a camera attached to a robotic arm takes thousands of images of cells, seeds, roots, and shoots. The images record traits such as leaf color, root development, and shoot size, giving researchers clues to the relationship between a plant’s genotype, the growing conditions, and the observable traits of its phenotype.
It will take big data tools to help researchers store, manage, and analyze all the photo data collected by the instrument.
“The system will largely facilitate plant phenotyping experiments that are impossible by current techniques,” Dong says.
As the toolkit develops, Dong says he hopes to move beyond plants and use it for studies of insects or even small fish. One day, he hopes to have a commercial instrument that can be used by biological researchers around the world.
Funding from Iowa State’s Plant Sciences Institute and the National Science Foundation supported the project.
Source: Iowa State University