Closely sown corn plants communicate to defend themselves

"Corn plants whisper messages to each other to defend against their enemies. When they are very closely planted, they release a volatile substance that induces their neighbors to produce chemicals that halt their growth, but activate their defenses against plagues. And that's not all they also modify the soil's microbiota, leaving a defensive legacy that preps the immune system of the next generation of plants."

"This discovery, published in Science, opens the door to the use of the plant's own components as pesticide. Using an impeccable experimental design, a group of Chinese, Swiss and Dutch researchers looked at how to improve the conditions and consequences of high-density corn cultivation. For decades, closely planting rows of it and other grains, like wheat and rice, has led to increased production of crops that are essential for the world's population."

"Scientists experimented by planting some fields with a low density of 60,000 plants per hectare and others with double that, at 120,000 per hectare. They saw that while there were no major differences at the edges of the two types of field, the interior plants of the super-populated fields modified their root system and reduced the height of ears, chlorophyll concentration and number of kernels per ear."

Closely planted corn emits a volatile compound that induces neighboring plants to produce chemicals that slow growth while activating defenses against pests. High-density stands show altered root architecture, reduced ear height, lower chlorophyll concentration, and fewer kernels per ear among interior plants. High-density fields experienced significantly less pest damage despite reduced growth metrics. Closely planted corn also alters soil microbiota, creating a defensive legacy that primes immune responses in subsequent generations. Experiments compared low-density (60,000 plants/hectare) and high-density (120,000 plants/hectare) plantings and found density-dependent chemical signaling intensity explains the induced defensive responses.

Read at english.elpais.com