In 1924, Dr. Katherine Esau was working on a sugar beet farm in California, where some of the beet plants were suffering from a strange virus called curly-top disease.
Spread by insects called leafhoppers, it causes plants to have unusually curly leaves and stunts their growth.
By paying careful attention to the anatomy, or the internal structure of these plants, Esau discovered how the disease spread throughout the plant.
She wrote in her autobiography: "I began to realize that the virus must enter and must move in the plant along a pathway.
I figured out that if the leaf-hopper passes the virus by feeding, then the virus must be moving through the same system as the food moves." In other words, the very same group of cells that move the sugar produced by photosynthesis from the leaves to the rest of the plant was being hijacked to transport the virus all throughout it.
This discovery was huge for the field of botany because it helped illustrate just how essential the knowledge of healthy plant anatomy is for understanding unhealthy plants — and helping them get better.
So, stick out your tongue and say "ahhh," plants.
Let's explore what's going on in there.
Hi! I'm Alexis, and this is Crash Course Botany.
Just like human bodies, plant bodies are made up of tissues, which are organized groups of cells that have similar structures and functions.
