Plants are extraordinary. In this post I explain three very surprising facts about plants that made me fall in love with them during graduate school: Plants have immune systems, all plant cells can act as stem cells, and plant cells are actually immortal.
As an undergraduate, I sat through human biology lectures, shouldered up with ambitious pre-meds at the University of Colorado. When they marched off to anatomy, I wandered into the councilor’s office, wondering what biology careers don’t require memorizing musculature.
I met with professor emeritus and plant biotechnology enthusiast Andrew Staehelin who insisted, “you should get a PhD in Plant Biology at UC Davis”. Thinking to myself “UC where?” I applied for a graduate program in a subject I’d never studied at a University I’d never heard of.
When I got to the University of California in Davis I learned two important things:
- “What’s your favorite plant?” is everybody’s favorite ice-breaker question
- “I dunno, the kind you eat” is not an appropriate answer
So when a seed company recruiter started my internship interview with “What’s your favorite…” I was relieved that she finished with “…thing about plants?” Now that is a question I can answer. After 4 years studying plant biology, I still don’t have a favorite plant, and my plant taxonomy skills are lacking, but I have learned a whole lot about how plants work from the brilliant faculty and students at UC Davis.
So as an-ex human molecular biologist who’s come over to the plant side, here are my three favorite things about plants:
- Immunity: Plants have immune systems too! Plant immune systems are actually somewhat similar to human and animal immune systems. They can even be vaccinated against viruses. For example scientists inserted a bit of DNA from the papaya ring-spot virus into the papaya genome. The resulting disease-resistant plants saved the Hawaiian papaya industry. Studying disease response in plants also contributes to our understanding of human disease pathology. In fact, microorganisms were first found to be a cause of diseases in plants! (Think Irish potato famine)
- Indeterminacy: All plant cells are indeterminate or “totipotent”-as in-“totally capable”. This means that every single plant cell acts as a stem cell, which, under the right conditions, can develop into a whole new plant. Check out this picture of a rose flower sprouting a whole new plant from the UC Davis Plant Transformation Facility. Totipotency is what makes “clonal propagation” possible. For example, all bananas are actually clones of one parent banana, the Cavendish. Instead of reproduction by seeds, every new banana plant is grown from the cutting of another. Many other food crops such as apples and strawberries are also clonally propagated.
- Immortality: Unlike animal cells, plant cells can essentially live forever. Although whole plants don’t typically live forever due to environmental factors, plant cells are not limited in the number of times they can divide. That’s why trees can grow for thousands of years, and seeds can germinate after tens of thousands of years.
In conclusion, plants are pretty amazing and very underrated. Plants tend to blend into the background of our existence, like buildings or landscapes. This phenomenon is called “plant blindness.” But plants are quite dynamic, and we rely on them for food, oxygen, medicine, fuel, fibers, and more. Further, plant research has significantly contributed to our understanding of human disease. Nonetheless, basic plant science is seriously underfunded and understudied. I hope to counter plant blindness by sharing facts and new discoveries in my “That’s Plantastic” segment. I’m happy to answer (or more likely find an expert to answer) any questions you have about plants in the comments section.