The tall seedlings are the most common and most easily formed abnormal seedlings in rape seed beds. The main reason for the formation of tall seedlings is that the seeding volume is too large, the fertilizer and water are too much, and the seedling age is too long. As a result, the main stem has been elongated in the seedbed, and the early and mid-maturing varieties are particularly serious. This kind of seedlings is easy to fall after transplanting into the field, easy to leave the leaves and expose the neck. Once it encounters the cold current, the stems are easily frozen and cracked, which will lead to high branches and high yields. Therefore, there is a tendency to grow crops in due course. The seedlings are sprayed with paclobutrazol at the 3-leaf stage, generally using 15% paclobutrazol per acre for 50 grams, spraying 40-50 kilograms of water, which can prevent the tall seedlings formed in the rapeseed field.
Too early to plant the seedlings too early after the temperature is too high, the leaf growth rate is fast, the seedlings are too long and vulnerable to cold damage due to winter; too late sowing, the temperature is low, the leaf speed is slow, unfavorable autumn and winter strong.
Appetite seedlings occur when the available nitrogen fertilizer is used excessively, the temperature is relatively high and the humidity is relatively high, it is easy to cause growth and over-prosperity and the formation of leggy seedlings. As the growing trend is strong, the organization is tender, and the resistance is not strong. After transplanting into Daejeon, the leaves often wither a lot, turning green slowly, making seedlings late, and being prone to freezing, which is not conducive to strong winter spring hair. The prevention method is proper sowing and control. Fertilizer, and time seedlings, Dingmiao. For the seedlings with prosperous tendencies, 50 to 100 ppm of Chlorothorean spray can be used for 4 leaves and 1 heart.
Thin and thin seedlings, also known as "shady foot seedlings"
Mainly due to seedbed conditions, seedlings crowded and shaded and lack of light, grow thin and weak, chlorophyll less, the prevention method is to prepare enough seedbeds, the general seedbed should account for about 20% of the planting area, seedbed fertility and other elections, texture loose, drainage and irrigation convenient . After emergence and time seedlings, seedlings can not emerge seedlings, seedlings can be set at the 3 leaf stage, once the seedlings, should be poured once the fertilizer and water to benefit strong seedlings.
The dwarf plantlet is also called stiff seedling, mainly due to the slim soil on the seedbed, the insufficient supply of fertilizer and water, or the long-term waterlogging of the seedbed, poor root development, or late sowing. The seedling growth in the seedbed is insufficient and is also caused by the low temperature of the cold wave. The seedlings have short stems, fine roots and necks, few leaves, small and short leaves, and low chlorophyll content. As a result, photosynthesis is weak, growth is stagnant, and the leaf color is red. Strong spring production requires high yields and low yields. The prevention method is suitable for seedling age, and 35-40 days is appropriate for seedlings of early and mid-maturing varieties to prevent drought and prevent flooding. This will prevent the development of seedlings from being impeded by drought and prevent the development of seedlings, resulting in the formation of sterile seedlings, insufficient seedbed base fertilizer and seedbed growth. In the period of severe shortage of fertilizer and water supply, it is necessary to promptly spray the fertilizer on the leaves or topdressing the soil in order to make up for lack of soil fertility and promote rapid growth of seedlings.
Too early to plant the seedlings too early after the temperature is too high, the leaf growth rate is fast, the seedlings are too long and vulnerable to cold damage due to winter; too late sowing, the temperature is low, the leaf speed is slow, unfavorable autumn and winter strong.
Appetite seedlings occur when the available nitrogen fertilizer is used excessively, the temperature is relatively high and the humidity is relatively high, it is easy to cause growth and over-prosperity and the formation of leggy seedlings. As the growing trend is strong, the organization is tender, and the resistance is not strong. After transplanting into Daejeon, the leaves often wither a lot, turning green slowly, making seedlings late, and being prone to freezing, which is not conducive to strong winter spring hair. The prevention method is proper sowing and control. Fertilizer, and time seedlings, Dingmiao. For the seedlings with prosperous tendencies, 50 to 100 ppm of Chlorothorean spray can be used for 4 leaves and 1 heart.
Thin and thin seedlings, also known as "shady foot seedlings"
Mainly due to seedbed conditions, seedlings crowded and shaded and lack of light, grow thin and weak, chlorophyll less, the prevention method is to prepare enough seedbeds, the general seedbed should account for about 20% of the planting area, seedbed fertility and other elections, texture loose, drainage and irrigation convenient . After emergence and time seedlings, seedlings can not emerge seedlings, seedlings can be set at the 3 leaf stage, once the seedlings, should be poured once the fertilizer and water to benefit strong seedlings.
The dwarf plantlet is also called stiff seedling, mainly due to the slim soil on the seedbed, the insufficient supply of fertilizer and water, or the long-term waterlogging of the seedbed, poor root development, or late sowing. The seedling growth in the seedbed is insufficient and is also caused by the low temperature of the cold wave. The seedlings have short stems, fine roots and necks, few leaves, small and short leaves, and low chlorophyll content. As a result, photosynthesis is weak, growth is stagnant, and the leaf color is red. Strong spring production requires high yields and low yields. The prevention method is suitable for seedling age, and 35-40 days is appropriate for seedlings of early and mid-maturing varieties to prevent drought and prevent flooding. This will prevent the development of seedlings from being impeded by drought and prevent the development of seedlings, resulting in the formation of sterile seedlings, insufficient seedbed base fertilizer and seedbed growth. In the period of severe shortage of fertilizer and water supply, it is necessary to promptly spray the fertilizer on the leaves or topdressing the soil in order to make up for lack of soil fertility and promote rapid growth of seedlings.