Nitrogen deficiency
After flowering, the symptoms were obvious, the plants were short, and the growth was weak. The leaves were pale green and then yellow. In severe cases, the leaves of the leaves were cup-shaped. In the late growth stage, the leaflets of the base leaflets were completely chlorotic and shrivelled, and sometimes they were fiery. The leaves fall off and the yield is low. Control measures: Early application of nitrogen fertilizer can be used as a seed fertilizer or seed dressing. When nitrogen deficiency was found, foliar spray of 0.2%-0.5% urea solution or nitrogen-containing compound fertilizer was sprayed in time.
Phosphorus deficiency
Early phosphorus deficiency affects root development and seedling growth. In the absence of phosphorus, the plants are short, stiff, dark green, and the leaves are rolled up; the phosphorus deficiency occurs from the buds to the flowering stage, the leaves shrink, the color is dark green, and the petioles, leaflets, and leaves are severe. The margins are upwards and do not expand horizontally. The area of ​​the leaflets is reduced and the color is dark green. Prevention and control measures: The phosphorus-deficient field is increased with organic fertilizer and ditch is applied with calcium phosphate or diammonium phosphate as the base seed fertilizer. When phosphorus deficiency was found, the leaves were sprayed with 0.2%-0.3% potassium dihydrogen phosphate solution or 0.5%-1% superphosphate calcium leaching solution.
Potassium deficiency
Symptoms develop from bottom to top, symptoms appear first in the lower leaves, plant growth slows, internode shortening, clustered; leaf tip and leaf margin become brown and fade, brown necrotic spots or plaques often appear on leaves. The tips of the leaflets atrophied, the leaves curled downwards, and the veins subsided; when the potassium deficiency was severe, the plants showed "top dryness". Control measures: Basal fertilizer mixed with 200 kg of ash. 40 days after planting, long-term application of potato fertilizer is performed with 150-200 kg of plant ash or 10 kg of potassium sulfate. It is also possible to spray 1% potassium sulfate solution 40-50 days before harvest, once every 10-15 days, once every 2-3 times.
Calcium deficiency
A pale green band appeared on the leaf margins of early apical buds of young apical buds. After necrosis, the leaflets shrank or twisted. In severe cases, apical buds or axillary buds died. The roots are prone to necrosis, the tubers are small, and there are abnormally formed strings of small tubers with necrotic spots in the marrow of the tubers. Prevention and control measures: In the soil with strong acidity, calcium deficiency is prone to occur. Apply appropriate amount of lime to supplement the deficiency of calcium in soil or adjust soil pH. When calcium deficiency was found, the leaves were sprayed with 0.3%-0.5% calcium chloride solution in time, once every 3-4 days, for a total of 2-3 times.
Magnesium deficiency
Potatoes are more sensitive to magnesium deficiency. In the absence of magnesium, the leaves, leaf margins, and veins of the old leaves fade from the green to the center, and later lower leaves become brittle and thicken. Control measures: Apply sufficient organic fertilizer to improve soil physical and chemical properties, so that the soil remains neutral, if necessary, lime can also be used to adjust to avoid the soil acid or partial alkali. Magnesium-deficient fields should be treated with magnesium sulfate such as magnesium sulfate or dolomite. When magnesium deficiency was found in the plant, the 0.5%-1% magnesium sulfate solution was sprayed on the leaves in time, once every two days, and sprayed 3-4 times.
Boron deficiency
The growth of the root and stem ends is stopped. In severe cases, the growth point is necrotic, and the lateral buds and lateral roots are sprouted and the branches and leaves are clustered. The leaves are rough, wrinkled, curled, thickened and brittle, shriveled, wilted, wilting, petiole and shoots thickened and shortened, cracked, corked, or spotted or lumps. Tuber brown necrosis. Control measures: Borax-free soil 0.5 kg borax per acre. When the boron deficiency occurred in the plants, a 0.1% borax solution was sprayed on the leaves.
Zinc deficiency
The growth of the plants was inhibited, the internodes were short, the top leaves upright, the leaves were small, there were gray to bronze irregular spots on the leaves, and the leaves curled upward. When severe, brown spots appear on petioles and stems. Control measures: Zinc-sulphate soil base application of 0.5-1 kg of zinc sulfate. Zinc deficiency was found in the plants, and 0.5% zinc sulfate solution was sprayed on the leaves and sprayed once every 10 days.
Manganese deficiency
Symptoms first appear on new leaflets, pale green or yellow after chlorosis between veins, almost all white veins between severe veins, and many brown patches along the veins. In the end, the small spots die and fall off, rendering the leaves incomplete. Prevention measures: Due to the high soil pH caused by the lack of manganese, should be more acidic fertilizers such as ammonium sulfate to reduce the pH, such as the lack of manganese in the soil itself, can be 2000 grams of manganese sulfate per acre base.
Iron deficiency
Symptoms first appear on the young leaves. The iron-deficient leaves are chlorotic and white, and the heart is often white. It is called chlorosis. In the initial period, the veins faded and the veins remained green. The color of the veins was deeper than that of the leaves. The color circle was clear, and the chlorotic tissue curled upwards. In severe cases, the leaves turned yellow and turned white. Control measures: Foliar spray 0.5%-1% ferrous sulfate solution 2-3 times.
China Extract Powder For Use As Dietary Supplement Extract Powder, Extract Powder Manufacturer
Shaanxi Kang New Pharmaceutical co., Ltd. , https://www.bio-pharmacies.com