What causes empty sunflower seeds? Latest cause analysis
The sunflower is a relatively common flower in our daily life, and its seeds are the sunflower seeds we often eat. The market demand for sunflowers is very large, so the planting area is also constantly expanding, but as more and more are planted, sunflowers have gradually developed some problems. One of these is empty seeds, which can seriously reduce sunflower yields. So what causes empty sunflower seeds? How should they be prevented and controlled? Let's take a look below!
1. Water
Cause: Sunflowers have relatively strong cold resistance, but during the flower disc growth period they need a large amount of water. If water is lacking at this stage, the empty seed rate will rise and yield will decline. Lack of water during the production period, and failure to water in time, is the main cause of empty sunflower seeds.
Prevention and control: We should strengthen water management in sunflower cultivation, observe sunflower growth, and water in time when the soil is too dry. Also, during the flower disc growth period, the frequency of watering should be increased to avoid drought affecting flower disc growth.
2. Temperature
Cause: Sunflowers do not have high temperature requirements. When seeds germinate, keeping the temperature above 4 degrees is enough, and when seedlings emerge the temperature should be adjusted to about 9 degrees. However, many times it is improper temperature management by growers that causes seeds to fail to adapt after sowing, hindering germination and seedling emergence, affecting the coordinated reproductive and vegetative growth of sunflowers, and causing empty seeds.
Prevention and control: During cultivation we still need to adjust the surrounding temperature properly. After sowing, try to keep the temperature at 8-10 degrees to promote seed rooting and seedling emergence. After germination, adjust the temperature to about 30 degrees. Throughout the growth period, the temperature must not exceed 44 degrees or fall below 4 degrees, otherwise growth will be seriously affected.
3. Light
Cause: Everyone knows that sunflowers love sunlight very much, and sunflower leaves, flower discs and so on all have very strong phototropism. If light is insufficient, seedling growth is hindered, stems and leaves lack nutrients during the growth period, the flowering and pollination rate decreases, and seed setting is insufficient. This causes sunflower seeds to be not plump enough, and the empty seed rate increases greatly.
Prevention and control: During the growth period, sunflower plants slowly move with the growth of the sun, so we must ensure there is sufficient light. If sudden weather changes occur, lights should be turned on promptly for artificial supplemental lighting, to avoid sunflowers losing their growth direction and affecting the seed setting rate.
4. Density
Cause: The planting density of sunflowers is greatly related to the variety. Oil-type varieties have relatively short plants, so although they can be planted somewhat densely. But if planting density is blindly increased, the sunflower population structure becomes chaotic, and plants compete with each other for water, nutrients and light. This leads to insufficient light energy utilization and increases the empty seed rate of sunflowers, resulting not only in insufficient yield but also in greatly affected quality.
Prevention and control: When planting, we must control planting density well according to the variety, environment, soil fertility and various other aspects, to avoid planting too densely and causing sunflower plants to affect each other. We should create a good growing environment for sunflower growth, reduce the empty seed rate of sunflowers, and increase yield.
The sunflower is a cross-pollinated crop, and the success rate of natural pollination is low, which can also cause empty sunflower seeds. Therefore, during the sunflower pollination period, we should use artificial pollination or insect pollination methods to increase the pollination rate of sunflowers and reduce the empty seed rate. Of course, nutrition, continuous cropping and so on are also main causes of empty sunflower seeds, and these are all things everyone needs to pay special attention to during cultivation. Only by reducing the empty seed rate can high and abundant yields be ensured and one's cultivation benefits expanded.