Re: Do plants send signals through the air to other plants?

I guess what you are really asking is "are plants intelligent?" Are plant capable of warning other plants when danger appears? There was a book published several years ago that reported these very findings. I have included a link for this book.

The Secret Life of Plants

This book is entertaining, however the jury is still out on the author's findings.

Plants are capable of detecting if there are neighboring plants close by using light. As you know plants absorb light energy from the sun and change it to chemical energy. The pigment chlorophyll is responsible for absorbing the light energy. There are other pigments in the plant that are just as important as chlorophyll to the growth of the plant.

When plants grow crowded together there is not enough light for all of the plants to grow to their fullest potential. A pigment called phytochrome is able to detect changes in the light reaching the plant. When phytochrome "senses" a decrease in light an action called 'shade avoidance' is started. The plant begins to grow taller trying to put its leaves above the leaves of the other plants and receive more light. An example of this shade avoidance is a corn field. The plants on the outside edges are shorter than those in the middle of the field because there is not as much competition for light on the edges.

I have included a link which might give you some ideas on science fair projects with plants.

Plants-T he Secret Life of Plants

I hope this helps.

Gary