MySheen

Effective prevention and control of cotton stiff seedlings

Published: 2024-11-22 Author: mysheen
Last Updated: 2024/11/22, After cotton transplanting, it is the plum rain season, with low temperature, more rainy days and less light, which leads to the slow turning green of cotton seedlings, the postponement of flower bud differentiation and the formation of "rigid seedlings". The main types of rigid seedlings are as follows: first, waterlogging damage to rigid seedlings. It is common in low-lying cotton fields, where waterlogging seedlings are formed by overcast and rain for a long time, resulting in blackening of roots, gray-green leaves and slow growth. Second, drought harms stiff seedlings. Mainly due to drought, the leaf yellow dry red wine, the amount of new roots is less, the growth is very slow, and the proportion of red stems is large. Third, fat harms stiff seedlings. The main reason is that the application of base fertilizer is too shallow.

After cotton transplanting, it is the plum rain season, with low temperature, more rainy days and less light, which leads to the slow turning green of cotton seedlings, the postponement of flower bud differentiation and the formation of "rigid seedlings".

The main types of rigid seedlings are as follows: first, waterlogging damage to rigid seedlings. It is common in low-lying cotton fields, where waterlogging seedlings are formed by overcast and rain for a long time, resulting in blackening of roots, gray-green leaves and slow growth. Second, drought harms stiff seedlings. Mainly due to drought, the leaf yellow dry red wine, the amount of new roots is less, the growth is very slow, and the proportion of red stems is large. Third, fat harms stiff seedlings. The main reason is that the application of basic fertilizer is too shallow, and the direct contact between fertilizer and cotton seedling root causes thick fertilizer to hurt the root, which is characterized by dark and red leaves, often accompanied by physiological disease spots, and thin roots. Fourth, weak and rigid seedlings. Poor quality of soil preparation, extensive transplanting, planting too deep or too shallow, lax soil sealing caused this kind of rigid seedlings, resulting in small and weak seedlings, atrophy is not long. Fifth, stiff seedlings of diseases and insect pests. The damage of Fusarium wilt, anthrax, Fusarium wilt, thrips, cotton aphids and other diseases and pests often cause cotton seedlings with missing holes or curls in leaves, yellowing and redness in leaf color, less root fineness, compact internodes, dwarf and rigid seedlings.

After the occurrence of stiff seedlings, we should carefully find out the causes and carry out symptomatic prevention and treatment. For the stiff seedlings caused by waterlogging, it should be drained to cool down and protect the roots, and the waist ditch, chamber ditch and enclosing ditch should be opened with a high standard to ensure that the rainstorm in May and June can be drained quickly, and the groundwater level should be lowered to less than 60 cm so that the rain can be kept dry. And timely ploughing and dispersing wet, deep hoe between rows, shallow hoe between plants, to increase the temperature and supply oxygen for the early development of cotton seedlings.

For the stiff seedlings caused by early injury, the most effective method is watering, which can be watered by alternate lines or water diversion points, and must not be flooded to restrain the rise of ground temperature.

For ossified seedlings damaged by fertilizer, scientific fertilization should be applied to promote early development. The basic fertilizer should be reasonably matched and applied deeply, and about 2500 kg of farm manure, 40 kg of compound fertilizer and 1.5 kg of boron fertilizer should be applied per mu to prevent and control the ossified seedlings of element deficiency type. All cotton fields with obvious fertilizer damage to rigid seedlings should carry out a shallow ploughing, irrigate water once in a sunny day, and then spray 0.1%-0.4% zinc sulfate, ferrous sulfate and other micro-fertilizers.

For weak rigid seedlings, the cotton field before transplanting should be carefully arranged into narrow deep ditches, fine soil leveling, uniform soil fertilizer, virtual and solid, so as to prevent hanging roots and provide a comfortable environment for the early development of cotton seedlings. After transplanting, we should cultivate the soil in time to promote the development of root system, combined with cultivating soil, loosening soil, and promoting transformation. The middle ploughing should be shallow first and then deep, and the choked roots of the soil should be low first and then high, and should be carried out step by step, generally 8 cm and 10 cm. Combined with topdressing fertilizer, a small amount of fertilizer is applied for many times, generally, 2kg urea per mu is applied to water, and 6mu can also be poured with 6-8 piculs of thin human and animal manure water. Each topdressing should be carried out after ploughing.

For the stiff seedlings caused by diseases and insect pests, we should prescribe the right medicine to the case and do a good job in prevention and control on the basis of field investigation. In addition, urea 3kg / mu can be applied, and 0.2% potassium dihydrogen phosphate solution can be sprayed on the leaves for 2 times, so as to promote the early recovery of cotton seedlings.

 
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