Many biostimulants available on the market are intended to improve plant tolerance to “abiotic stresses”. This term is becoming more and more common thanks to recent research shedding light on plant physiology and in particular, on the way plants react to stress.
There are two types of stress : biotic and abiotic. Biotic stress results from harm caused to a plant by a living organism, for instance an insect or a fungus. Abiotic stress is caused by ambient conditions. These can be, for example, extremes temperatures, a lack or an excess of water, a nutrient deficiency, strong winds, excessive salinity or a herbicide treatment.
A plant experiencing an abiotic stress is a handicapped plant. This stress hinders its growth and development, and eventually affects crop yield and quality. And not just a little bit. In their book titled “Plant Abiotic Stress,” M. A. Jenks et P.M. Hasegawa from Purdue University claim that abiotic factors provide the major limitation to crop production worldwide.
The impact of abiotic stress has been suspected for a long time. In 1982, J.S. Boyer wrote in Science magazine that adverse environmental conditions lead to losses exceeding 50 % in main crops. This scientist believed that low water supply was the most common abiotic stress limiting crop growth around the globe. In 2000, in the magazine Biochemistry and Molecular Biology of Plants, E.A. Bray concluded that abiotic stress caused yield losses between 51% and 82% in annual crops.
It would be impossible to remove all abiotic stress, except maybe in a fully controlled environment such as a greenhouse but the latest research shows that we can help plants tolerate this stress. This is where biostimulants enter the scene.