In this article, we consider what root pressure and its effect on plants are. All plant life, even the tallest trees, has gravitational properties that allow nutrients to be absorbed from the largest depths of the soil and move to the highest branches. We will consider that plants have an amazing ability to transport water and nutrients up, using a complex set of biological processes.
The concept of root pressure
Consider what is root pressure, definition. This is an effort that helps bring fluids up into the water vessels (xylem). Xylem is a plant vascular tissue that transfers water and dissolved minerals from the roots to the rest of the plant, and also provides physical support. Xylem consists of many specialized water-conducting cells. It is mainly generated by osmotic pressure in the root cells.
Water spreading to the roots from the surrounding soil rises through the trunk and branches of the tree before entering the leaves. The pressure on the trees is several times higher than atmospheric. And this is not enough to transfer water to the top of the tallest trees. In addition, root pressure is usually the lowest when water is lost from leaves (transpiration) and is highest when trees need water most.The lifting force arising from the evaporation and transpiration of water from leaves, as well as the adhesion forces of molecules in vessels and, possibly, other factors contribute to the growth of juice in plants.
Pressure of the root system of plants. Details
Not everyone knows what root pressure is. Plants are complex organisms, and one of the many intriguing plant processes is root pressure. It is it that allows water and nutrients to rise to all parts of the plant. So what is root pressure? It is necessary in order to promote or inhibit the absorption of nutrients.
In other words, the root system of a plant can change its pressure:
- help water or nutrients rise throughout the plant;
- push water or nutrients out of a plant.
Biologists are usually concerned about how this affects the rise of water and nutrients in the plant. Root pressure is the transverse osmotic pressure in the cells of the root system. It makes the juice rise through the stem of the plant to the leaves.
Operating principle
What is root pressure and how does it appear? It occurs in the xylem of vascular plants when soil moisture is high, either at night or when transpiration is low during the day. It is studied by removing the shoot of a plant near soil level. Xylem juice will be released from the slice within a few hours or days due to root pressure. If the pressure gauge is attached to the cut rod, the root pressure can be measured. Root pressure is due to the active distribution of mineral nutrient ions in the root xylem.
It is caused by the accumulation of water in xylem. This water puts pressure on the cells. Root pressure provides a force that pushes water up the stem, but this is not enough to take into account the movement of water towards the leaves at the top of the tallest trees. The maximum root pressure measured in some plants can only lift water up to 6.87 meters. And the highest trees - above 100 meters.
Root pressure value
Root pressure is very important in plants of any size, since the endoderm - the inner layer of cortical cells - will only transport water and nutrients up the stem or stem of the plant. Water and nutrients are absorbed by the root system from the ground and sent through osmosis in combination with the pressure of the root system up the plant stem. Nutrients and water are then sent to the leaves of the plant to provide the raw materials needed for the photosynthesis process.
During photosynthesis, water and carbon dioxide are absorbed by the radiant energy of the sun to produce glucose, which is necessary for the vital processes of plant cells. As a rule, the larger the plant, the greater the pressure of the root. Plants, such as trees, can reach hundreds of meters in height, so increased root pressure is necessary to get water and nutrients to the topmost areas of the tree.