The mystery of plant fever

 　　In the icy and snowy Arctic, the cold is almost all year round. Even in summer there, the temperature is often below 0℃, but the plants that grow there can blossom and bear fruit in the snow and ice. Scientists are surprised to find that the temperature of the flowers of these plants is always higher than the outside temperature.

　　Why do the flowers of these plants emit heat? Scientists have been puzzled. In the 1980s, Swedish botanists discovered that the flowers of most plants in the Arctic have the habit of turning toward the sun. Therefore, they suspected that this might be related to the increase in temperature of the flowers.

　　In order to confirm whether this speculation is correct, they did an interesting experiment: fixed the calyx of a plant living in the North Pole with a thin iron wire, so that it could not turn towards the sun, and placed a belt on the flower. The temperature difference of a very thin metal probe is used to measure the temperature of the flower. When the sun rose, scientists measured that the temperature of the fixed flowers was 0.7°C lower than that of the unfixed flowers. This result seems to unravel the mystery of the warming of Arctic plants' flowers.

　　 However, scientists later discovered that in the swamps of central South America, a plant called stinky cabbage grows. In March and April every year, when the weather is still quite cold, its flowers are already blooming. According to measurements, during the two-week flowering period, the temperature of the buds of skunk cabbage is always 22°C, which is about 20°C higher than the surrounding air temperature.

　　 Obviously, the theory of plants turning toward the sun cannot explain the wonderful phenomenon that the temperature of stinky cabbage buds is 20°C higher than the surrounding air temperature.

　　There are many plants that can generate heat in nature.

　　Liliaceous herbs will have heat. Scientists have found that when the ambient temperature is 4°C, the temperature of some Liliaceae herb flowers can reach 40°C.

　　Araceae plants also have heat, and their pistils and stamens are hidden deep in the buds. The heat generated during heating will be evenly distributed throughout the buds, melting the snow covering the plants.

　　Through research and exploration, botanists finally uncovered the mystery of plant fever.

　　Skunk cabbage heats up because there are many thermogenic cells in its flowers. The thermogenic cells contain an enzyme that can oxidize the organic matter produced by plants through photosynthesis, thereby releasing a lot of heat. In order to invite the "matchmaker" after the flowers bloom, stinky cabbage makes the temperature of the flowers rise sharply and emits the smell of hot, rotting animal carcasses or fermented dung piles, so it is an insect that likes to eat rotting things. So he hurried over to "act as a matchmaker" for them and completed the task of pollinating them.

　　Liliaceae plants heat up because they have stored a lot of fat in the tissues of the flowers before they bloom. When it blooms, fat enters the tissue cells and undergoes strong oxidation, which releases a large amount of heat energy.

　　Araceae plants produce heat and also use fat as fuel to generate heat. The heat generated can turn the surrounding wind into a vortex that revolves around the flower, and this vortex is not affected by the direction of the outside wind, and can turn the wind blowing in all directions to the opening of the flower bud. In this way, the mature pollen at the top of the flower is blown into the unpollinated flower below. This ensures that even if there is no insect pollination, the plants themselves can use hot air to pollinate.

　　So, what is the significance of plant heating to itself?

　　Scientists believe that the heat of plant flowers can promote the fragrance of flowers and attract insects to pollinate them. In addition, heat-generating plants mostly grow in cold places. Heat-generating is beneficial to the material transportation and biochemical reaction in the plant, thereby improving the plant's resistance to severe cold. At the same time, the temperature in the flowers of heat-producing plants is much higher than the outside temperature, which naturally becomes an ideal place for insects to keep out of the cold. When insects come to lodge, they also help spread pollen. Therefore, heating plants is actually an adaptation to the cold environment.