ABSTRACT

Plants exposed to environmental stresses often exhibit a variety of symptoms or indications. Stress indicators are signs of disturbance, either as visible, growth or morphological modification or invisible, physiological or biochemical changes that relate to repair and resistance mechanisms. Evaluating physiological and cellular parameters for assessing the severity of stress injury or level of stress tolerance is not always trivial; visual performance ratings are most often subjective. Your neighbor’s lawn always looks greener, although objectively it is not always true. The scientific reasoning behind this claim is that it all depends literally on the angle you are looking at, whether you are looking directly above your lawn, seeing all the open spaces, or looking at your neighbor’s lawn at a certain angle, seeing only the upper green parts.