What is the significance of the 1992 murder case in Phoenix Arizona referred to in Criminal Justice Investigations college courses as the Palo Verde Seedpod Case?

This case was shown on many crime-reconstruction television programs in the US.

In May 1992 the body of a woman was found in the brush near some paloverde trees in Maricopa County, Arizona. She was identified as Denise Johnson. They found some evidence nearby and had a suspect, but the evidence was circumstantial at best. They noticed damage on a paloverde tree and thought a vehicle had caused it. They obtained a search warrant for their suspect's truck and found seed pods from a paloverde tree in the truck bed. The suspect denied being at the crime scene or killing her.

They sent samples to a university professor, a plant molecular genetics specialist named Dr. Timothy Helentjaris of the University of Arizona. He proved the plant DNA from the paloverde seed pods found at the scene matched the paloverde seed pods from the suspect's truck. The professor used a RAPD (randomly amplified polymorphic DNA) test. It was the first time plant DNA was tested for a forensics cae, admitted into evidence, and resulted in a guilty verdict. That makes the 1992 Palo Verde Seedpod Case very significant.