By Maud Hinchee, PhD, Chief Science Officer, Agricen Sciences
Have you ever marveled at a dandelion that forced its way through an asphalt road to sunshine? Or have you wondered how a Venus fly trap knows when to snap its jaws shut to capture its prey? Or how that pesky sedgegrass in your lawn seems to come back in greater numbers in the face of herbicides and hand pulling? Plants, including crop plants, are constantly responding to their senses. They can see, touch, smell, taste and sense water, food and predators—and they can remember. Of course, they don’t do all of this exactly the way a human does, but they do respond to messages they receive from the world around them to survive, thrive and extend their family through reproduction—much the way we humans do.
This is a pretty stimulating idea – that plants are actually sentient beings responding to stimuli in a purposeful manner. The idea is nicely illustrated in the PBS series Nature, in an episode entitled “What Plants Talk About.” The program shows examples of plants demonstrating apparently “purposeful” behavior and communicating with each other as well as with potential friends and foes.
More recently, scientists convened to discuss plant behavior in July 2014 at the “Biostimulants and Plant Growth” meeting in Raleigh, North Carolina. They were interested in the use of a variety of naturally-derived products—in both in agricultural and horticultural applications—to signal plants through bioactive chemical messages to improve their growth, health and nutritional value.
These biostimulant products include humic and fulvic acids, seaweed extracts, protein hydrolysates, amino acids and microbial inoculants. Typically, such products are organically complex and are not completely characterized biochemically. This has meant that their positive impact on horticulture and agricultural production has been traditionally viewed with skepticism by many scientists.
However, one of the presentations at the conference offered a “reality check” as to whether these types of products have positive effects on plants. The presentation was based on a scientific review article by Dr. Joseph Kloepper of Auburn University, his PhD student Pamela Calvo and their colleague Agricultural Uses of Biostimulants” in the May 2014 issue of the journal Plant and Soil.
We are just beginning to comprehend the significant potential of biostimulants as a way to communicate with plants – essentially “tipping them off” as to how to positively adjust to the environmental and biotic challenges typical of agricultural systems. I, along with other contributors, will further explore this fascinating area in a series of future posts.