Rice deficiency symptoms and remedies

Rice requires a certain amount of nitrogen, phosphorus, potassium and trace elements at every stage of growth. Once it is deficient, it affects growth and development and leads to reduced yield. After deficiency, the symptoms are often manifested from the leaves. Therefore, during the growth of early rice, the color and shape of the leaves and plants should be observed frequently, and the type of deficiency should be distinguished and remediated immediately.
Nitrogen deficiency and yellowing. The nitrogen deficiency of rice seedlings generally begins to yellow downward from the old leaves, gradually extending from the base leaves to the heart leaves, and finally the whole plant falls yellow. Nitrogen deficiency can cause the rice seedlings to be short, the leaf axils are different, the tillers are late and thin, the leaves are short, narrow and erect, showing yellow-green color, resulting in short plants, less tillers, premature aging, small ears, and insufficient seeds. Remedy: At this time, nitrogen fertilizer should be added, and 5-7 kg of urea should be applied. If the nitrogen deficiency is serious, the application should be slightly increased, and the application of phosphorus and potassium fertilizer should be applied. After the application, the cultivation should be carried out to promote the transformation of yellow seedlings.
Phosphorus deficiency and redness. After the early rice seedlings returned to green, the growth was significantly slow, the tillers were delayed or not divided, or the symptoms of dead seedlings appeared after returning to green. The leaves were thin and erect. In severe cases, the leaves were curled and folded along the midrib, and the leaves were dark and dull. Blue-violet, far away, the dark green belt of the rice plant is gray-purple; the rice plants are cluster-like, short and thin; the roots are not tight, the new roots are few, and sometimes the complications of hydrogen sulfide poisoning occur. Phosphorus-deficient rice often has premature aging. Remedial measures: shallow water topdressing, acre of calcium phosphate 30 kg mixed ammonium bicarbonate 25-30 kg, with the application, immediately after application. Or use 0.2% potassium dihydrogen phosphate solution, spray 50-60 kg per mu with the prepared fertilizer solution. Shallow irrigation and irrigation on the pipe water, repeated exposure to increase soil temperature, strengthen the ability of rice roots to absorb and metabolize phosphorus. When new roots are born, 3-4 kg of urea per mu is promoted.
Deficiency of potassium red bumps. Potassium deficiency in early rice, although rooting can be turned back after transplanting, but the leaves are yellowish brown spots, red-brown spots appear at the tip and leaf edge of the old leaves, and finally the leaves gradually change from apical to red-brown. Every time a new leaf grows, it will increase the lesion of an old leaf. In severe cases, only a few new leaves remain green in the whole plant, which looks like a fire. The peasant image says that it looks red and looks like no insects. The entire root of the diseased plant is yellowish brown to dark brown with few new roots. Potassium deficiency is mainly caused by cold soaked fields, rust paddy fields and muddy fields in early rice. Remedial measures: Immediate drainage, 100-150 kg of wood ash per mu, or 4-6 kg of potassium chloride per acre, put the field water before fertilization, take strips or holes, and apply 5-10 cm deep into the soil; Or foliar application of 1% potassium chloride or potassium sulfate solution, combined with nitrogen fertilizer interstitial irrigation to improve the ability to absorb fertilizer.
Zinc deficiency is sick. Zinc-deficient early rice seedlings first appeared chlorotic yellow-white-like in the mid-inferior mid-vein region, with reddish-brown spots and irregular plaques, which gradually expanded into reddish-brown streaks, which turned red and brown from the tip of the leaves. The lower and upper leaves appear in sequence. The leaf speed of the diseased plants slowed down, the new leaves were short and narrow, and the new leaves faded, especially near the basal midrib. The leaf occipital distance of seriously ill plants is shortened or dislocated, obviously dwarfed, the sheath is longer than the leaves, the jointing is difficult, the tillers are loose and grassy, ​​and the maturity is delayed. Although the slender rice ears are extracted, most of them are not strong. Remedy: Immediately drain the fields, aerate the ventilation, and promote root development. When the rice seedlings are deficient in zinc, the zinc sulfate is formulated into a 0.1%-0.2% aqueous solution for foliar spraying, and the prepared zinc sulfate fertilizer solution is used in an amount of 50-60 kg, and sprayed once every 7 days. Just spray 2 times.