The types of severe seedlings are nitrogen deficiency disease, phosphorus deficiency disease, potassium deficiency disease, and zinc deficiency disease. The symptoms are not the same due to the different number of nutrients.
Symptoms of nitrogen deficiency seedlings are short, with few tillers, small leaves, yellow-green to yellow, yellow leaves from the tips of the leaves to the midrib, and then extended to the whole leaf, with short ear and small grains, forced to mature earlier. Nitrogen deficiency reasons: First, the use of base fertilizer is insufficient, can not be timely fertilizer to the seedlings; Second, poor soil texture, fertilizer performance is not strong; Third, salt washing is not thorough; Fourth, base fertilizer over-application.
Symptoms of phosphorus deficiency and stiff young leaves are dark green, old leaves are grayish purple, leaves stand upright, and sheaths are long and short. In severe cases, the leaves are curled, and the roots are few and clingy. They are black. Deficiency of reasons: First, the lack of available P in soil; soil two cold soak, water temperature is low, is difficult to absorb phosphorus; three soil reducing toxic substances that inhibit the absorption of phosphorus roots, causing physiological Deficiency.
Symptoms of potassium deficiency and stiff seedlings were thin, dark green leaves, and few tillers. The leaves rose from the bottom upwards, from the tips of the leaves to the base of the leaves, with yellow-brown spots, sometimes involving the sheath stalks, commonly known as rapae. Damage to the roots is prone to aging, shedding, new roots and perishable. The reason for the lack of potassium is that the effective potassium content in rice fields is low; second, partial nitrogen fertilizers cause malnutrition, leading to potassium deficiency; and third, toxic substances inhibit the absorption of potassium.
Symptoms of zinc deficiency seedlings in the new leaves, chlorosis, whitening, the old leaves of the base tip dry, the leaves from the bottom up in the middle of the threat both sides of the red or reddish-brown irregular rust, then gradually expand the contiguous, the new leaf is small, the leaves Slow, leaf sheath short, plant dwarf, all the old dead leaves dead. Zinc deficiency reasons: First, neutral or alkaline soil lacks effective zinc; Second, long flooding time; Third, a large number of phosphorus induced zinc deficiency; Fourth, the soil temperature is low, affecting the absorption of zinc.
The symptoms caused by the four kinds of elemental deficiency caused by the severe seedlings are different, but the causes of the stiff seedlings have many common points. Therefore, comprehensive prevention and control measures should be taken.
Clearing drainage gutters and improving cold soaking environment Whether it is a lakeside plain or a mountainous hill, all cold-soaked rice fields generally have deep silt and poor drainage, resulting in low soil temperature and water temperature, affecting the emergence of rice seedlings. In response to this, four kinds of paddy fields that lack nutrients should be well-opened to remove excessive waterlogging from the fields in time, prevent flooding, and encourage shallow irrigation.
To improve the soil in paddy fields, timely paddy fields should be used for soils that are more viscous than sand and soil, and salts with high salt content should be salt-washed. For those who have already emerged from the trend of zombies, they should be diligent in paddy fields or drained water to increase the soil temperature and promote new roots.
Neutralization measures are adopted to exclude the use of poisonous gas to acidify the soil or apply organic fertilizers that have not yet been decomposed to cause high levels of organic acids in the field. Huiminfeng or Zhuangfuxing active liquid fertilizers can be sprayed to remove germs. Because the pH of the fertilizer is 8.0-9.2, it has a strong neutralizing effect and has a significant control effect. It uses liquid fertilizer of 150 ml per acre and sprays 50 kg of water.
If the difference between different seedlings and the deficiency of nutrient elements are all missing, it shall be supplemented when topdressing. For lack of a single element, what is missing. If zinc is deficient, about 1.5 kg of zinc sulfate should be added per acre. For nitrogen deficiency, phosphorus deficiency, and potassium deficiency, while supplementing phosphorus and supplementing potassium, appropriate addition of nitrogen fertilizer, in addition to the role of nitrogen, can also improve the Phosphorus, potassium absorption.
Hand & Foot Mask,Foot Mask,Dead Skin Removing Foot Mask,Nourishing Tender Foot Mask
Guangzhou Lingxue Cosmetics Co., Ltd , https://www.lxgj188.com