The period from the germination of sunflowers to the blooming of the flower tray is indeed sun-oriented. Its leaves and flower discs follow the sun from east to west during the day, although not instantaneously. Botanists have measured that the orientation of the flower disc is about 12 degrees behind the Sun, or 48 minutes. When the sun goes down, the sunflower disc slowly swings back again, and at about 3 a.m., it faces east again and waits for the sun to rise. How did this wonderful phenomenon happen?
Scientists have found that under the irradiation of sunlight, the content of auxin on the backlit side of the sunflower increases, which stimulates the cells on the backlit side to elongate, so as to slowly rotate towards the sun. After the sun sets, auxin redistributes, and the sunflower slowly turns back to its starting position, which is the east. However, once the flower plate is in full bloom, the sunflower no longer rotates towards the sun, but is fixed towards the east.
So why do you end up facing east instead of other directions or upwards?This is probably the result of natural selection, which is beneficial for the reproduction of sunflowers. First of all, the pollen of sunflowers is afraid of high temperatures, and if the temperature is higher than 30 degrees Celsius, it can be burned. Therefore, a fixed orientation to the east avoids direct midday sunlight, reduces the amount of radiation and protects pollen from high temperatures.
Secondly, the flower plate is exposed to sunlight early in the morning, which helps to dry the dew that condenses at night. This reduces the likelihood of mold infestation and keeps the flowers healthy. In addition, on cold mornings, the sun's flower trays turn the sunflower's flower trays into warm nests, attracting insects to stay there to help pollinate. This is very important for the reproduction of sunflowers.
In addition to the above reasons, there are other factors that may also influence the choice of sunflower. For example, the flower disc of a sunflower needs plenty of sunlight for photosynthesis to produce enough energy to support the growth and flowering process. Facing east, the flower disc is fully exposed to sunlight and provides the required energy.
In addition, the flower disc of a sunflower also needs a certain amount of wind to spread pollen. Facing east makes the flower disc more susceptible to breezes from the east, aiding in pollen dispersal and the pollination process.
To sum up, the reason why sunflowers always turn to the sun is due to the action of auxin and the result of natural selection. Facing east protects pollen from heat damage, reduces the likelihood of mold infestation, and provides plenty of sunlight and wind to support the growth and reproduction process. This wonderful natural phenomenon is not only amazing, but also brings us wisdom and wonderful thinking about nature.
The amazing journey of the sunflowers shows us the wonder and wisdom of nature. By turning towards the sun and eventually facing east, it both protects its own reproductive process and attracts insects to help pollinate. There are many scientific principles and the results of natural selection behind this small plant. Let's cherish the beauty and wisdom of nature even more!