Natural stress plant growth. When there is no water in the soil there are not very many nutrients to support plant growth. Drought also enhances the effects of wind. When drought occurs the soil becomes very dry and light. The wind picks up this dry dirt and carries it away. This action severely degrades the soil and creates a poor condition for growing plants. Plants have been exposed to the elements for thousands of years. During this time they have evolved in order to lessen the effects of abiotic stress. Signal transduction is the mechanism in plants that is responsible for the
Plant physiology gravity or sunlight, is called a tropism. A response to a nondirectional stimulus, such as temperature or humidity, is a nastic movement. Tropisms in plants are the result of differential cell growth, in which the cells on one side of the plant elongates more than those on the other side, causing the part to bend toward the side with less growth. Among the common tropisms seen in plants is phototropism, the bending of the plant toward a source of light. Phototropism allows the plant to maximize light exposure in plants which require additional light for photosynthesis, or to minimize it