Plants live in vastly different environments on the planet and employ a variety of tactics to complete their life cycles or continue their lives. What all plants have in common is their use of five “classic” hormones—auxin, cytokinin, gibberellins, abscisic acid, and ethylene to control their growth and development.

Photo: Scott Dworak

These hormones are biomolecules, molecules made by the plant; they can move to targeted locations and serve as internal signals to induce a plant response. This hormone-induced growth response in plants is complex; understanding the process is an ongoing quest for plant biologists. To add to this complexity, plant biologists have discovered biomolecules that control plant growth, in addition to the five classics. One of these discoveries is another plant hormone called jasmonic acid (JA).

Photo: Adam Hays

Jasmonic acid plays an important role in a plant’s response to stress, specifically when the plant is wounded or physically damaged. Stress of all kinds is a major problem for plants, and since plants can’t flee from their problems, they rely on internal mechanisms to deal with the stress they encounter. Because stress presents such a major problem for plants, scientists want to understand how jasmonic acid works in controlling the stress response. One team of scientists committed to understanding the role of jasmonic acid in plant growth is led by Dr. Paul Staswick at the University of Nebraska-Lincoln. Dr. Staswick’s approach to science is to design and carry out experiments that test a hypothesis based on his team’s or other scientist’s previous discovery. Careful analysis of the experimental outcomes determine if the hypothesis is supported or needs refinement. This leads to the next experiment. The approach requires patience, attention to detail and creativity. This lesson will focus on one set of experiments that were conducted by Scott Dworak, a graduate student who was a part of Dr. Staswick’s research team.