Few people think, but sunflowers play an important role in modern human life. And who lived in the summer in villages where there are fields with this plant, he could notice a certain feature of it. During the day, the sunflower constantly looks at the Sun, gradually turning from east to west, and at night returns to its original state in order to again catch the sun's rays in the morning. How and why does he do it?
Sunflower structure
Externally, sunflower is easy to distinguish from other flowers. It has a high sturdy stem, the height of which is capable of reaching five meters. At its tip, the bud gradually turns into a yellow-orange flower. In the core of the fruit seeds are gradually formed - black seeds used as food and oil production.
Interesting fact: a sunflower penetrates deep into the ground. Sometimes their depth can reach up to 30 meters. Because of this, it can be quite difficult to extract an adult sprout without damaging it.
Long flat leaves grow from the stem, the length of which can reach 50 cm. They are covered with thin white hairs, which serve as protection against strong heat.
Use by people
Archaeologists believe that for the first time sunflowers began to grow in North America, about two thousand years ago. From there, it gradually spread to other countries. Some Native American peoples considered the flower the personification of the sun god because of the characteristic shape and color.
In Russia, a sunflower appeared during the reign of Peter the Great. The emperor first saw him while in Holland.Since the flower had a beautiful appearance and could be used for food, he ordered the seeds to be brought to Russia. Surprisingly, he took root well in the local climate and quickly spread across the peasant fields.
In 1829, sunflower oil was first obtained in the world. Around the same period, the first Russian plant opened, where they began to produce it on an ongoing basis. The low cost of production made it possible to charge a small price for goods, and even poor people could afford it.
Interesting fact: The ordinary serf peasant Dmitry Bokarev invented sunflower oil, who had previously practiced the creation of oils from other plants and products.
Since then, under the sunflowers, they began to allocate whole fields where they were engaged in their cultivation. Since the flower ripens within 30 days in the summer, this allowed for three months to collect crops 2-3 times a year. Now other countries are engaged in the production of sunflower oil, but Russia and Ukraine remain the undisputed leaders in this industry.
Turn behind the sun
In botany, there is a separate term that is called the gradual rotation of flowers to the Sun - heliotropism. Studies have shown that this property is inherent in almost all colors, but in sunflowers it is more pronounced.
Why does he turn to the sun? The answer is quite simple: to get more heat and rays of light that stimulate its growth. Scientists experimented and deliberately prevented the rotation of the flower, fixing it in place.As a result, “limited” samples grew 10% slower.
Interesting fact: it was found that when the sunflower is turned to the Sun, bees pollinate it more actively. A warm surface attracts insects more than a cold one.
How does a flower turn?
At its base are motor cells that can stretch and contract due to the production of potassium. It depends on their position in which direction the top will look. The plant literally understands where to move the base of the stem to position the flower in the right direction.
The movement of sunflower corresponds to a 24-hour circadian rhythm. Scientists tried to “trick” the plants by artificially changing the duration of the movement of the light source to 30 hours. In this case, the sunflowers moved unevenly, which affected their growth, biomass and yield.
Sunflowers turn towards the Sun to receive more heat and grow more intensively. They do this with the help of motor cells that can change their shape. Located at the base of the flower, they smoothly rotate it towards the Sun, and at night return to its original state.
