Calcium deficiency symptoms
Recently, there has been a lot of rain. After a sunny day after the rain, symptoms of calcium deficiency are prone to occur, and calcium deficiency is more likely to manifest itself in sandy soil plots.
When a plant is calcium deficiency, symptoms such as new roots, apical buds, and fruits that grow vigorously and young are first observed, and when it is light, the symptoms are withered and necrosis occurs.
The front of the root becomes brown, and the long texture of the branches and leaves becomes soft, affecting the accumulation of sugar in the fruit. The fruit powder is light, the fragrance is light, the new shoot is poor in maturation, and the tree vigor becomes weaker.
One: Calcium Deficiency Performance of Fruits and Crops
Fruit trees need a lot of calcium during the fruiting period. If they are lacking or nutritional imbalances, they will cause malnutrition, weaken immunity, be vulnerable to various bacteria and get diseases, reduce the quality of fruits, and reduce production in the coming year.
* After the lack of calcium in the apple tree, the nutritional imbalance caused the yellow leaves to fall early, and the trees were full of small red fruits.
* The young leaves on the fresh shoots appear faded or necrotic spots, and the tips of the leaves and the leaf margin curl downward.
* Older leaves may appear dead.
* The fruit often suffers from bitter pit disease, with subsidence spots on the surface, soft flesh tissue and bitter taste.
* Apple water heart disease is also caused by calcium deficiency. The flesh of the apple is translucent. It spreads radially outward from the center. Finally, the gap between the flesh cells is full of juice and causes internal decay.
After the grape is deficient in calcium, the leaves are yellow, small, thin, and rolled. The size and size of the grapes are severe, they are easy to drop fruit, crack fruits, young leaves and veins blew green, and there are gray-brown spots between the veins, followed by needle-like necrotic spots near the edge of the leaves. The tip of the stem is dead.
After calcium deficiency in kiwifruit, the leaves are yellow, smaller, curled, without texture, susceptible to ulcer disease, the fruit is easy to soften off, and the shelf life and shelf life are shortened.
After the citrus is deficient in calcium, the leaves are small and thin, soft and no texture, and the fruit size is uneven.
After pomegranate calcium deficiency, fruit cracking often occurs during the growth period, resulting in less fruit.
Peach-deficit young shoots from the top of the young leaves from the tip and the leaf margin or along the midrib to produce a red-brown or dark brown necrotic area, severe when the tips and leaves of the shoots like fire-like, more serious when the top of the branchlets dry wither, a large number of fallen leaves.
After jujube lacks calcium, fruit cracking will begin in the soon-to-be mature period. In severe cases, the fruit cracking rate will be above 60%.
The leaves of the tobacco are light green, and the top buds are bent downwards. The tips and edges of the young leaves wither. The plants dwarfed and were abnormally dark green, and when they were extremely lacking, the top buds died. Thickening of the lower leaves, sometimes with some dead red-brown spots. If calcium deficiency during flowering, flowers and buds have a tendency to wither. The top of the corolla died, causing the pistil to stand out prominently and there may be dead spots on the corolla.
The same is true of food crops. When calcium deficiency occurs, the leaves are thin and small, and the cold-resistance and drought-resistance are poor. The rods are easy to fall down, the grains are not full, the yield is low, and so on.
The growing point and the tip of the stem are dead, the plants are dwarf or clustered, and the young leaves often cannot be unfolded, and the grown leaves often show a lack of green. Roots are short, branches are numerous, and the root tips secrete clear mucus, which appears to be attached to the root tip.
Plants are short, leaf margins are sometimes white with serrate irregularities, and the top of the stem is curved. The growth of the new leaf is obstructed. Almost completely chlorotic. The transparent glue is secreted, the tip of the leaf is stuck, and it cannot stretch properly. The leaf margins of the leaves are white, transparent, sawtooth and irregularly broken, and the brown brown scorch appears on the tips of the leaves. Old root tan.
Light green stripes appear on the edges of young leaves and the leaves shrink. In severe cases, the apical bud died, and the lateral buds grew outward, showing clusters. The roots are prone to necrosis, the tubers are small, and there are abnormally formed strings of small tubers. The surface of the tuber and the internal vascular bundle cells often become necrotic.
Symptoms first occur in the root and the young part of the ground, the plants are short, and the tissues are aging, showing premature aging. The young leaves curl and the heart is dry. The stereotyped front end of the heart and yellowish green leaves, the old leaves are still green, but the leaf shape is curled, there are few fruits, and there are many empty valleys. The root is short and short, and the new root becomes brown at the cutting edge.
The leaves curl, and old gray spots appear on the old leaves, the veins turn brown, and the petioles are weak, drooping, and soon die of wilt. The top of the stem is curled like a hook, and the new young leaves cannot stretch and die easily.
The first true leaf was malformed, with irregular white spots on the edges and leaves of the old leaves, and scars on the back. Then brown dead leaves appeared on the front of the leaves. The petiole became weaker, more empty, and the seeds were not full.
The plants are short, the leaves are aging, there are few fruit branches, and there are few bells and knots. The growth point of the terminal buds is severely inhibited. The hooks are bent, the leaves are bent downwards, and the old leaves fall off prematurely. When the calcium is severely depleted, the petioles of the new leaves droop and ulcerate.
16. Chinese Cabbage (Brassica oleracea)
In the early stages of ball growth, the edges of young leaves became water-streaked and translucent. The leaves of the heart and leaves first appeared tan, thin, or rot. Afterwards, they gradually developed toward the middle wraps and the outsole leaves. See some of the leaves of the heart turned white, yellow, dry, mesophyll was dry paper, with banded or irregular lesions (heart dry cabbage).
In severe cases, the outer leaf margins appeared water-stained and gradually yellowed and dried off. The re-tanning plots and sandy soils performed more clearly. In case of continuous rainy weather
(or during storage) induces bacterial infection to accelerate decay.
* The upper leaves turn yellow, the lower leaves remain green, growth is blocked, and the top buds often die. Young leaves are small, easy to brown and die. Stems often appear near the top of the stem. The roots are thick and short, and the flowers are less detached. The top flowers are particularly easy to fall off.
* The fruit appeared with umbilical rot. At the beginning of fruit enlargement, the umbilical pulp appeared water-soaked necrosis. Afterwards, the diseased tissue collapsed, darkened, shrank, and subsided.
* The margins of the leaves resemble gold edges, and there are transparent white spots between the veins. Most veins are chlorosis, and the main vein is still green. The plants are dwarfed, the internodes are short, the top section becomes shorter, the new leaves are small, and they dry out from the edges in the later stages.
* When the calcium deficiency is severe, the petioles become brittle and easy to fall off. The plants start to die from the top and the dead tissues are gray-brown. The flower is smaller than normal, the fruit is small, and the flavor is poor.
Two: Role of calcium
Calcium is an element that does not easily flow (especially in rainy weather). It is mostly found in stems and leaves. Old leaves are more than young leaves. Fruit is less than leaves. Calcium can only be transferred unidirectionally (upwards).
The transportation of mineral elements in the plant body is generally through the phloem and xylem, but calcium can only be transported through the xylem in the plant, mainly by transpiration, and transported from bottom to top by transpiration.
It is easy to lose calcium after it rains. When the rain is fine, plant transpiration gradually becomes stronger and the content of absorbed calcium becomes stronger. However, due to rain, part of the calcium is taken away by the flowing water, the calcium content in the soil becomes low, and the supply is low, so it is prone to calcium deficiency. symptom.
In addition, calcium is easily fixed in plants. Calcium is easily precipitated in insoluble calcium salts in plants. It is an element that cannot be reused. When calcium is fixed, it will no longer flow. This is why the calcium deficiency phenomenon first appears on the top young leaves.
The calcium content of plants is about 0.2%~1%, and the calcium content of different plants varies greatly. In general, dicotyledonous plants have higher calcium content than monocotyledons, and dicotyledonous plants have higher calcium content in legumes. Plants with high calcium content include clover, peas, peanuts, cabbage, and red cabbage in vegetables.
Persimmons, cucumbers, bell peppers, carrots, onions, potatoes, and tobacco.
(1) A mesangial layer of a plant cell wall is formed in the form of calcium pectinate, so that cells and cells can be connected to form a tissue, and a plant organ or individual has a certain mechanical strength. Calcium deficiency causes abnormal chromosomes.
(2) Metabolic processes in neutralizing plants produce excessive and toxic organic acids, especially calcium and oxalic acid combine to form insoluble calcium oxalate and eliminate organic acid poisoning.
(3) Calcium is a component and activator of some enzymes in plants. For example, calcium is a component of a-amylase, and adenosine triphosphatase also contains calcium and the like.
(4) It contributes to the stability of the cell membrane, promotes the absorption of potassium ions (k), and delays cell aging.
In addition, there are reports that calcium can also reduce the dispersion of protoplasmic colloids, enhance the viscosity of the protoplasts, coordinate with potassium ions, regulate the normal activities of the protoplasm, and maintain the water-fillability, viscosity, elasticity, and permeability of the cells. The normal physiological state is conducive to the normal metabolism of the crop.
(5) The application of calcium in combination with boron and molybdenum has obvious effect of increasing production. Applying calcium fertilizer to calcium-deficient soil not only can supplement calcium in plants and soil, but also can improve the soil to raise the pH, so as to reduce or eliminate the harm to soil properties and plant physiology caused by large amounts of iron, aluminum and manganese ions in acid soil. . Reduce the fixation of phosphorus on the soil, regulate the supply of trace elements to the soil, improve soil microbial living conditions, enhance soil aeration and water permeability, and thus improve soil fertility.