A question for those wishing to grow crops in space is how plant seeds know which way is “up” and which way is “down.” While there is no gravity in space, an up and down gravity orientation is crucial to plant growth and development on Earth.

Marshall Porterfield, associate professor of agricultural and biological engineering, suggests that plants sense gravity through a process that develops a bioelectric field within plant cells. He and colleagues will test a new type of biosensor capable of measuring ion currents in multiple locations around a single cell. The MISA chip ?EUR??,,????'??+ for microfluidic ion sensor array ?EUR??,,????'??+ is a collection of sensors that detect ion motion in very small volumes of a sample.

“The challenge of this project is that we need to have very small probes to measure very small electric fields around very small cells,” Porterfield says. “This development has the potential to change biology by providing information at considerably higher precision than was previously possible.”The Purdue team will be based at the Johnson Space Center in Houston for its flights.