Renewable Farming

Sound of a chewing caterpillar triggers a plant’s chemical defenses

AgWeb is currently reporting a University of Missouri study released last year documenting how a flowering plant sharply increased its production of mustard oils when it “hears” the sound of a chewing caterpillar. 

Caterpillar on leaf

The university release includes a brief video which replays the sound, so you can hear what the plant hears. The plant reacts the same whether an actual caterpillar is chewing, or only the sound is played.

This is one more incident among dozens which demonstrate how plants can react to protect themselves against threats from pests, whether they’re insects or pathogens. One of the best collections of this data is the book (sand a film), The Secret Life of Plants, by Peter Tompkins and Christoper Bird.  Amazon carries it, and so does the ACRES USA bookstore.  For your convenience, here’s a link to the ACRES book catalog. The Secret Life of Plants is listed on page 50 of the catalog.  While ordering that, we recommend another fascinating classic by the same authors, Secrets of the Soil.

In the late 1970s and early 1980s, we worked extensively with Sonic Bloom, a foliar spray product which contained humates, auxins and cytokinins. The developer also included a programmed sound system which broadcast frequencies across a wide range of bird song harmonics. The combination of sound and plant growth regulators had clear-cut growth benefits for crops. However, the spray material, as recommended, cost about $50 per acre. OK for greenhouses but too costly for corn and soybeans. 

Another classic book, Tuning in to Nature, by Philip Callahan, reveals why insects are attracted only to sick plants while healthy plants repel them. 

The point of reporting this: The “modern” pest control mindset is to exterminate pests with poisons. However, toxins — herbicides or insecticides — have a weakening effect on plants’ natural defense mechanisms. Most are chelating agents, acting by locking up essential elements.

We need to learn more about using intensive nutrition as the means of building plant defenses against insects and disease. That’s a role of our WakeUP: Amplifying the yield benefit of nutrients by an average of 80%.