The yellowing of wheat has caused psychological panic among individual farmers. Wheat seedlings often due to lack of hormone factors, diseases and pests, adverse weather conditions, resulting in growth of wheat seedlings severely hampered the emergence of yellow, and now it is the main reason for several control measures, Chinese pesticide Xiaobian to introduce you to the following for Everyone's reference.
1. Deficiency causes yellowing and nitrogen deficiency. The plants are short and thin, with few tillers, narrow and erect leaves, yellow-green leaves, dry leaves, and gradually develop into yellow leaves at the base. Governance measures: 5-15 kg of urea can be chased or foliar sprayed with 2% urea solution, once every 7-10 days, even spray twice.
2. The potassium-deficient stalk is small and weak, the tip and edge of the old leaf turn yellow, and then extend inward along the vein. The macular and the healthy part are obvious. In severe cases, the tip of the old leaf and the edge of the leaf are coke-like, and the root is poorly developed. Premature aging. Control measures: Foliar spray can be carried out with 0.2% potassium dihydrogen phosphate solution, once every 7-10 days, even spray 2-3 times.
3, zinc deficiency The tip of the leaf stops growing, the whole leaf loses green and turns yellow and even turns white, the internode is shortened, and the plant is dwarfed. Governance measures: Spray 1 to 3 times per mus of zinc sulphate 1 kg or 0.2% zinc sulphate.
4. Manganese deficiency The leaves are soft and draped, the new veins are striped and chlorotic, and the veins are still green; sometimes the leaves are light green, the yellow stripes expand into brown spots, and the tips of the leaves appear to be scorched. Control measures: Apply 1 kg of manganese sulfate per acre to the surface of 1 kg or 0.1% of manganese sulfate.
5. The molybdenum-deficient leaves lose green and yellow, first develop from the tip of the old leaf to the edge of the leaf, and then spread inward from the leaf edge, first the spot, then connect into a line, and the yellow part of the severe part turns brown, and finally dies. . Control measures: 0.05% ammonium molybdate solution can be sprayed 1-2 times.
6. Magnesium deficiency The plants grow slowly, the leaves are grayish green, and sometimes the veins are yellowish. The younger leaves form greenish streaks between the veins or the whole leaves are white, and the old leaves are often early. Control measures: Foliar application with 0.02-0.04% magnesium sulfate solution.
7. Sulphur-deficient wheat plants often turn yellow, especially between veins, but the old leaves tend to remain green, and the plants are short and mature. Control measures: Foliar application with 0.5-1% potassium sulfate or ammonium sulfate solution.
Second, pests and diseases cause yellowing, and it is necessary to choose suitable pesticides for treatment.
1, wheat spider: sucking wheat leaf meat tissue nutrition, resulting in yellowing or even death of the leaves. Control measures: acre of 1.8% avicin 3000-5000 times liquid 30 kg spray.
2, root rot: Symptoms are root rot, leaf spots appear, stems die and so on. After the wheat returned to green, the disease appeared as yellow and the plant height was uneven. Governance measures: the roots are filled with 15% powder rusting 1000-1500 times.
3, sheath blight: sheath blight in the wheat seedlings mainly damage the leaf sheath leading to yellowing of the lower leaves. Control measures: 15% triazodone, 12.5% ​​hectare 1000-1500 times liquid 30 kg spray.
Third, bad weather conditions cause yellowing and freezing cold and cold: a few days before the yellowing, the wheat seedlings are green, and suddenly the leaves are yellow, and the yellowing is generally uniform, not yellow. Or a part of the blade (mostly in the middle of the blade) is yellow. Governance measures: watering in time before the cold current arrives; strengthen management after the cold current, spray foliar fertilizer.
Half-Type Shower Set,Brass Half-Tape Shower Set,Brass Shower Set,Luxury Shower Set For Family
Kaiping Rainparty Sanitary Ware Technology Co.,Ltd. , https://www.rpshower.com