Search results
Results from the WOW.Com Content Network
Transpirational cooling is the cooling provided as plants transpire water. Excess heat generated from solar radiation is damaging to plant cells and thermal injury occurs during drought or when there is rapid transpiration which produces wilting. [1]
Transpiration: the movement of water from root systems, through a plant, and exit into the air as water vapor. This exit occurs through stomata in the plant. Rate of transpiration can be influenced by factors including plant type, soil type, weather conditions and water content, and also cultivation practices. [ 6 ] :
Overview of transpiration. 1-Water is passively transported into the roots and then into the xylem. 2-The forces of cohesion and adhesion cause the water molecules to form a column in the xylem. 3- Water moves from the xylem into the mesophyll cells, evaporates from their surfaces and leaves the plant by diffusion through the stomata.
Directly - by measuring the reduction in mass of the potometer over a period of time. Here it is assumed that any loss in mass is due to transpiration. There are two main types of potometers: the bubble potometer (as detailed below), and the mass potometer. The mass potometer consists of a plant with its root submerged in a beaker.
Transpiration rates of plants can be measured by a number of techniques, including potometers, lysimeters, porometers, photosynthesis systems and thermometric sap flow sensors. Isotope measurements indicate transpiration is the larger component of evapotranspiration . [ 11 ]
In 1727, English clergyman and botanist Stephen Hales showed that transpiration by a plant's leaves causes water to move through its xylem. [ 50 ] [ note 2 ] By 1891, the Polish-German botanist Eduard Strasburger had shown that the transport of water in plants did not require the xylem cells to be alive.
The main cause behind this transpiration pull, water is lifted up in the plant axis like a bucket of water is lifted by a person from a well. Transpiration pull is responsible for dragging water at the leaf end, the pull or force is transmitted down to the root through column of water in the xylem elements.
Since photosynthesis, transpiration and stomatal conductance are an integral part of basic plant physiology, estimates of these parameters can be used to investigate numerous aspects of plant biology. The plant-scientific community has generally accepted photosynthetic systems as reliable and accurate tools to assist research.