Parasitic plant species are the bane of farmers everywhere – they can severely lower crop yields, and the chemicals capable of killing them often kill the desirable plants as well. In that regard, researchers at Virginia Tech have made a breakthrough discovery that sheds light on how parasitic species do what they do in the first place: By communicating via DNA, they “reprogram” their hosts into letting down their defenses.

“The discovery of this novel form of inter-organism communication shows that this is happening a lot more than any one has previously realized,” said Jim Westwood, a professor of plant pathology, physiology, and weed science in the College of Agriculture and Life Sciences. “Now that we have found that they are sharing all this information, the next question is, ‘What exactly are they telling each other?’.”

Westwood studied dodder (a parasitic weed) and its relationship with two host plants, Arabidopsis and tomatoes. He found that when the dodder uses its haustorium to penetrate its host, there’s an exchange of mRNA (the RNA that translates DNA and tells cells what to do based on it), which was previously inconceivable between two species.

Westwood says the exchange occurs on an unimaginable scale, with the two species effectively freely communicating. It’s believed that within the exchange, the parasite must “convince” the host plant to lower its defenses to allow for easier acquisition. The dodder is then able to siphon water and nutrients mostly uncontested.

The next phase of his study will try to determine what, exactly, the plants are “saying” to one another. Presumable “ouch, stop” on the part of the host, followed by “shhh, it’s ok” from the dodder?

The findings could be a boon for third-world nations, who struggle with invasive species when trying to feed people in some of their poorest regions. Westwood’s findings are revolutionary, but how to apply them is another question entirely.

“The beauty of this discovery is that this mRNA could be the Achilles hill [sic] for parasites,” Westwood said. “This is all really exciting because there are so many potential implications surrounding this new information.”