Potash fertilizer is one of the important fertilizers necessary for crops. Potassium fertilizer can promote crop nutrient transfer, fruit swelling, tissue maturation, accelerating growth and improving resistance. So, what are the manifestations of crop potassium deficiency? How to apply potash fertilizer correctly?
1. The straw becomes soft and easy to fall, with few tillers and poor tiller quality.
2. The tip and edge of the middle and lower leaves of the plant turn yellow and then brown, and the edges of the leaves are burnt and burnt; when the potassium deficiency is mild, the leaves will appear brown spots, but the veins and the middle of the leaves are still not green. When the potassium deficiency is severe The entire leaf will turn reddish brown or die and fall off.
3. After crops lack potassium, the root system will become shorter and fewer, and the plants are prone to premature senescence.
4. Potassium deficiency will also cause inconsistent fruit ripening period, and at the same time, the size will be smaller, the taste will be worse, and the quality will be lowered.
Correct application of potash fertilizer
1. Rotation potash fertilizer
In the rice-rice rotation, due to the application of organic fertilizer, late rice generally does not apply organic fertilizer, so potassium fertilizer should be applied to late rice. In the rotation of winter wheat and summer corn, potassium fertilizer should be used on corn first.
2. Reasonable combination of potash fertilizer varieties
For tobacco, sugar crops, and fruit trees, it is better to choose potassium sulfate, because the chlorine in potassium chloride is more suitable for fiber crops. Due to the high cost of potassium sulphate, potassium sulphate can be used for high-efficiency economic crops; for general field crops, it is better to use cheaper potassium chloride.
3. Foliar spray
When potassium-requiring crops are in the fast-growing period, foliar spraying is better. When crop roots are developing, it is best to apply deep layers. Commonly used conservation tillage leaves more crop residues on the surface of the soil, and also causes a higher concentration of potassium to accumulate on the surface of the soil and cannot penetrate deep into the soil. When the soil moisture is good, the potassium can infiltrate smoothly, but when the soil is dry, it will limit the absorption of potassium. As crops take root deeper below the most potassium-rich soil layer in order to get enough water, this dislocation can cause crops to be potassium-deficient. In this case, deep application of potassium fertilizer can significantly increase the availability of potassium.
4. Use base fertilizer and top dressing together
Most potash fertilizers are generally used as base fertilizer and early topdressing. The combined use of base fertilizer and topdressing has the best effect; when using potassium fertilizer, it is best to apply it deep into the wet soil layer, so that potassium ions are not easy to be fixed by the soil; comparison in weather and soil In the case of drought, it is better to spray potassium dihydrogen phosphate on the leaves.