Everyone knows that high potassium fertilizer should be applied at the fruit stage of strawberries, but why use high potassium fertilizer? What is the effect of potassium on the growth and development of strawberry fruit?
Potassium in plants:
Potassium plays an important role in the growth and development of plants. First of all, potassium ions are the activators of more than 60 kinds of enzymes in crops, which can enhance the photosynthesis of crops and promote the metabolism of carbohydrates. Secondly, potassium has a great influence on nitrogen metabolism and protein synthesis. At the same time, potassium can also increase the sugar reserves in the crop body, increase the osmotic pressure of cells, and thus increase the cold resistance of crops. Potassium is related to stem fiber synthesis and can promote the development of vascular bundles.
The main physiological functions of potassium ions in crops:
1. Promote photosynthesis: potassium can promote the synthesis of chlorophyll, improve the structure of chloroplasts, promote the assimilation of carbon dioxide in crop leaves, and strengthen leaf photosynthesis.
(Photosynthesis)
2. Promote the transport of photosynthetic products: the product of photosynthesis carbohydrates enters the transduction tissue from mesophyll cells and then transports to other organs, in which potassium plays an important role.
3. Potassium is an activator of many enzymes: potassium participates in the activation of more than 60 kinds of enzymes in crops, and through the activation of enzymes, potassium directly affects the synthesis and decomposition of protein and starch and the synthesis of oils. When the supply of potassium is insufficient, protein is broken down and amines increase, so the content of amines in crops can reflect the supply of potassium. At the same time, potassium can also promote nitrogen fixation of nodules.
4. Promote nitrogen absorption and metabolism: potassium is the companion ion of nitrate in the xylem transport process, and potassium plays an important role in nitrogen absorption and transport.
5. Adjust the opening and closing of the stomata of the leaf: when the light is sufficient, potassium ions can make the stomata of the leaf open, and when the light is insufficient or water is lacking, potassium can promote the rapid closure of the stomata to reduce the loss of water due to ineffective transpiration.
6. Enhance the stress resistance of crops: potassium mainly regulates the concentration of cells in the crop body, the permeability of cell membranes and the structure of cell walls, so that the drought resistance, high temperature resistance, cold resistance, salt resistance, lodging resistance, anti-aging and disease resistance of crops are improved, so potassium is often used as an anti-stress nutrient.
7. Improve crop quality: The impact of potassium on crop quality is not only manifested in increasing the content of nutrients such as sugar in the product, but also extending the storage time of the product and making the product more resistant to handling and transportation. Especially for vegetables and fruits, potassium can improve their appearance, color and taste, so potassium is often referred to as a quality nutrient. However, excessive potassium application can lead to an imbalance in crop nutrition, resulting in reduced crop yield and quality.
Potassium deficiency in strawberries mainly affects sugar accumulation and fruit expansion, so timely potassium fertilizer supplementation is an important node to improve the quality of strawberries.
Symptoms of potassium deficiency in strawberries:
Symptoms of potassium deficiency often appear after the results. The old leaves turn purplish-black and dry , while the youngest leaves remain healthy. Discoloration begins at the leaf margin, develops towards the leaf base, and affects the tissue between the leaf veins. The petiole and lower part of the leaf blade turn black and dry out. The youngest leaves are asymptomatic, which distinguishes potassium deficiency from boron deficiency. The affected plants have incomplete fruit coloration and tasteless taste. Typical symptoms of potassium deficiency are: yellowing and browning of the tips of the lower leaves.
Causes of potassium deficiency:
1. The soil does not maintain fertilizer: the sand soil is permeable and permeable, and the water and fertilizer cannot be retained in the soil, resulting in the loss of fertilizer and water applied to the soil.
2. Lack of soil organic matter: the soil is poor, and the application of organic fertilizer and potassium fertilizer is less when fertilizing, resulting in potassium deficiency in the soil.
3. Antagonism: excessive application of nitrogen fertilizer in the soil has an antagonistic effect on the absorption of potassium.
4, the root system is not good: the root is the root of crop growth, no roots do not stand, once the root system of strawberries has problems, the absorption of inorganic salt ions will be reduced, so root nourishment is the key.
Period of potassium supplementation:
Potassium is a large element for crops, and crops are in high demand, so they are supplemented throughout the growth period of strawberries. However, the demand for potassium in different growth periods is somewhat different, so it is necessary to adjust the fertilizer ratio in time. For example, during the nursery period and before strawberries flower, this period is dominated by balanced fertilizer; After strawberries enter the flowering and fruiting period, they need to be supplemented with high potassium fertilizer, but it should be noted that the potassium content of high potassium fertilizer should not be too high, generally not more than 35 potassiums.
How to supplement potassium:
Generally, when the base fertilizer is down, a fully rotted manure can be applied, which can reduce the phenomenon of potassium deficiency. Potassium sulfate, potassium nitrate type ternary compound fertilizer, etc. can also be applied when the base fertilizer is placed. Or topdressing balanced water-soluble fertilizer, foliar spraying 0.1%-0.2% potassium dihydrogen phosphate, grass ash leaching solution, etc. can be applied.
Note:
1. The absorption of potassium in different growth periods of strawberries is different, so the fertilization ratio should be adjusted according to the current growth period of strawberries.
2. Potassium plays a vital role in the crop body, but too much potassium will cause strawberry fruits to freeze, so the high potassium fertilizer applied at the fruit stage should not exceed 35 potassiums.
3. The utilization rate of strawberries to fertilizer in winter decreases, so it is recommended to apply a small amount of fertilizer many times, try not to apply too much fertilizer at one time, which not only does not play the role of supplementing nutrients, but also easily causes root burning phenomenon, affecting the growth and development of strawberries.
4. It is very important to top dressing in the later stage of strawberry cultivation, do not hold the early base fertilizer to apply sufficiently, and do not chase after any fertilizer in the later stage. This practice will not only lead to excess fertilizer in the soil, resulting in the accumulation of soil salt, but also affect the growth and survival of strawberries in the later stage.
2023 No. 64 China (Shouguang) Sino-Dutch soilless cultivation innovation technology
Registration for offline training courses is now!
November 8-12
Training content
1. High-efficiency strawberry seedling production technology;
2. Sharing of strawberry spring delayed harvesting technology; Common patterns of strawberry seedlings and application of innovative technologies;
3. Analysis of the management method and input of 50,000 jin per acre of Sapei tomatoes;
4. Cultivation technology and management method of watermelon in soilless cultivation
5. Green prevention and control of common diseases and pests of elevated strawberries and ground-grown strawberries;
6. High-efficiency planting management and marketing methods of potted vegetables and potted leeks;
7. New technology of green pollution-free vegetable prevention and control, high-pressure spray cooling system, substrate disinfection, organic agricultural input and other plant protection methods and machinery;
8. Application of artificial intelligence, big data and Internet of Things technology in horticultural production;
9. Cost accounting of soilless cultivation facilities and national shed design planning;
10. Comprehensive application of bumblebee and natural enemy insects in strawberry greenhouses
11. Water and fertilizer integration technology, facility water-saving irrigation technology, and water purification facility selection;
12. Ratio and practical application of nutrient solution of hydroponic leafy vegetables and substrate cultivated tomato fruits and vegetables;
13. Display and selection of new varieties suitable for high, medium and low-end picking gardens;
14. Greenhouse structure optimization and supporting cultivation technology mode;
15. Bumblebee biological pollination technology and its application on tomatoes;
16. Promotion and marketing of hydroponic leafy vegetable containers (plant factories), mainly overseas;
17. Planning and design of small and beautiful family farms under 30 acres;
18. Vegetable detector, inspection and organic and selenium-rich certification;
19. Green high-quality and efficient cultivation technology of facility crops (fruits and vegetables);
20. Facility soil ecological improvement and soil fertilizer (carbon-based fertilizer, soil conditioner, new fertilizer, etc.);
Scan the QR code above to sign up for the training course!
Places are limited and forecasts are fast
Registration consultation telephone: Mr. 13365369785 Du (same number as WeChat)