This is because the reaction has more kinetic energy up to a certain point, but at around 45 degrees celcius, the enzymes controlling photosynthesis start to be destroyed and cannot function. Light intensity and CO2 concentration increase both cause the rate of photosynthesis to increase while they are the limiting factor, but then plateau once another factor becomes the limiting factor.
The rate of transpiration can be affected by: light intensity, air movement, temperature and humidity. Increased light intensity will increase the rate of photosynthesis so more water is drawn into the leaves where photosynthesis primarily takes place and therefore the rate of transpiration is greater.
Air movement and humidity are linked. The rate of transpiration is directly related to whether stomata are open or closed. Stomata account for only 1 percent of a leaf's surface but 90 percent of the water transpired. Transpiration is a necessary process and uses about 90 percent of the water that enters a plant's roots. The other 10 percent is used in chemical reactions and in plant tissues.
Transpiration is responsible for several things:. The amount and rate of water loss depends on factors such as temperature, humidity, and wind or air movement. Transpiration often is greatest in hot, dry low relative humidity , windy weather. In order for a plant to grow and develop properly, it must balance photosynthesis, respiration, and transpiration. Left to their own devices, plants do a good job of managing this intricate balance. If a plant photosynthesizes at a high rate, but its respiration rate is not high enough to break down the photosynthates produced, photosynthesis will either slow down or stop.
On the other hand, if respiration is much more rapid than photosynthesis, the plant won't have adequate photosynthates to produce energy for growth. Hence, growth either will slow down or stop altogether.
When stomata are open, transpiration occurs, sometimes at a very high rate. A corn plant may transpire 50 gallons of water per season, but a large tree may move gallons per day!
Plants have problems if they lose too much water, so stomata close during hot, dry periods when transpiration is highest. However, CO 2 , which is needed for photosynthesis, also enters the plant through open stomata. Thus, if stomata stay closed a long time to stop water loss, not enough CO 2 will enter for photosynthesis.
As a result, photosynthesis and respiration will slow down, in turn reducing plant growth. Many herb plants produce lots of high-energy oils, which help them survive in the dry landscapes where they evolved. These oils help them survive extended periods of stomatal closure. To make a poinsettia bloom in early winter, indoor gardeners simply need to adjust the amount of light and darkness to "fool" the plant.
Oct 15, News story. Gardeners tend to think of fall as the time to put bulbs in the ground, but the warm soil and increasing moisture make it a great time to plant most anything.
This handbook will help you become acquainted with the growing and use of plants in gardens and home yard landscaping. It also describes how to make cut flower arrangements that you, your friends, and family can enjoy.
Information about garden planning, maintenance, cleanup, pest management, houseplants and indoor gardening for the month of November. I'm a certified, occupational chef, been making mashed potatoes for 30 yrs. I've noticed in the last couple of years, that red or golden Yukon, also boiler potatoes, are turning to glue, while whipping! No reason on earth I Sagar Sathuvalli Jan Featured question.
Lauren Grand Dec Featured question. Can green tomatoes still be wrapped in newspaper to help ripen. I understand that the ink for printing has changed and that newspapers were no longer good for wiping windows because of that change from a Petroleum to a soy base. Wonder if same held true for tomatoes? Pat Patterson Oct Featured question. This publication discusses the many types of fertilizers and soil amendments available for organic plant production.
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