What type of plant is the sunflower? A detailed guide to the latest plant classification
Sunflowers can be divided into general ornamental varieties and edible varieties. General ornamental varieties are characterized by shorter plants, usually no more than half a meter, so they are suitable for growing in pots. Edible varieties are taller, planted in ordinary open-air nursery soil, and can grow to more than 2 m. Now let us take a look at what type of plant the sunflower is!
What type of plant is the sunflower?
The sunflower is an angiosperm. In classification, the sunflower belongs to the angiosperms, and its fruit is an achene, commonly known as a sunflower seed, which is edible. The fruit consists of three parts: the pericarp, the seed coat, and the embryo. Edible-type seeds are longer, with black and white stripes on the pericarp in most cases; the pericarp is thick, accounting for more than 40% of the seed weight, and the 1000-seed weight is 100-200 grams. Oil-type seeds are shorter and smaller, with the pericarp mostly black and thin, about 20-30% of the seed weight, and the 1000-seed weight is 40-110 grams.
Why does the sunflower face the sun?
The stem of the sunflower contains a remarkable plant growth hormone. This growth hormone is very afraid of light, and as soon as it is exposed to light it moves to the shaded side, while also stimulating the cells on the shaded side to multiply rapidly, so the shaded side grows faster than the side facing the light, causing the sunflower to bend toward the light. At the same time, the sunflower facing the sun is also closely related to the effect of gravity.
The growing environment of the sunflower
1. Temperature: The sunflower is a crop that likes warmth and is also cold-tolerant, with strong adaptability to temperature. The seeds have a very strong tolerance to low temperatures. When the soil temperature is stable above 2°C, the seeds begin to germinate; at 4-5°C they can sprout and take root; when the soil temperature reaches 8-10°C, it can meet the needs of seed germination and emergence. Throughout the entire growth period of the sunflower, as long as the temperature is not lower than 10°C, it can grow normally.
2. Water: The sunflower is a crop that consumes a relatively large amount of water. The plant is tall, with many dense leaves, and its water uptake is 1.74 times that of corn. However, because its growth and development mostly coincide with local rain and heat, the contradiction between water supply and demand is not prominent, and the water requirements differ greatly at different growth stages. From sowing to budding, it needs little water; from budding to flowering is the peak period of water demand; from flowering to maturity, the water demand is also relatively high.
3. Light: The sunflower is a short-day crop and is not very sensitive to day length. It likes abundant sunlight, and its seedlings, leaves, and flower heads all have strong phototropism. With sufficient sunlight, the seedlings are sturdy and can be prevented from becoming leggy. Sufficient sunlight in the middle growth period can promote vigorous stem and leaf growth, normal flowering and pollination, and improve the seed-setting rate. Sufficient sunlight in the late growth period makes the seeds plump and full.
4. Soil: The sunflower has low soil requirements and can grow in all kinds of soil, from fertile soil to dry land, poor soil, and saline-alkali land. It not only has a relatively strong tolerance to saline-alkali conditions, but also has salt-absorbing properties. At the same time, the sunflower has a well-developed root system and relatively strong drought resistance. Moreover, the roots and stems of the sunflower have well-developed aerenchyma, making it very tolerant of waterlogging.