The leaves are the main organs of crop photosynthesis and the main organs for the production of crops. Therefore, in the production, it is very important to protect the blades to extend their functional time. The yellowing of tomato leaves in production is mainly yellowing of the middle and lower leaves, and a little yellowing of the top leaves.
The yellow leaves of the middle and lower parts are mainly yellow and middle leaves of the tomato plants. The yellow leaves gradually appear to develop into yellow leaves throughout the leaves, but mainly yellow veins and veins remain green. As the disease progresses, the leaves gradually become brittle, become brittle, become fragile, and age and fall off, which affects the normal growth of the whole plant, leading to premature aging of plants and tomato fruits.
Incidence rule:
In the middle and lower leaves, it develops gradually from the bottom to the top, in which the plants with weaker growth are more severe.
Disease analysis:
This is a symptom of magnesium deficiency in tomato, which belongs to a physiological disease and can be easily diagnosed as a bacterial disease. However, in this case, there is no lack of magnesium in the soil, but because the root system of the plant is poor in nutrient absorption, or the utilization of nutrient elements is not high, this happens. Mainly this year's climate anomaly. After the tomato colonization, first experienced a period of high temperature, and then experienced a long period of cloudy days, resulting in poor root environment of the tomato, poor root growth, affecting the normal absorption of nutrients in the tomato root; in addition to long-term photosynthetic plants The effect is poor, affecting crops to produce photosynthetic nutrients, and at the same time crops appear yellow (top leaves) due to lack of sufficient light for a long time.
Second, the top leaves yellow: yellow leaves on the top of the tomato, yellow for the entire leaf, the color is light yellow, including leaves and veins, leaves become thinner and smaller.
Disease analysis:
It is a physiological disease that may be related to the lack of iron and zinc in tomatoes.
Solution:
1. Spraying magnesium fertilizer: Spray the foliar fertilizers containing magnesium, such as Green Bole, Green Fenwei and 0.1% magnesium sulfate (that is, a two-to-three sprayer liquid), etc., and spray the lower leaves when spraying.
2. Spray foliar fertilizers containing iron or zinc: spray green fenway 2 or ruthenium green or 0.1% ferrous sulphate (ie 1 2 to 3 sprayer liquids), etc., supplement iron, main spray upper leaves . Note that ferrous sulphate is not suitable for direct application to the soil, otherwise it will damage the soil.
3. Rooting: You can use thiophanate-methyl 600 times as rooting agent, such as Fengshou No.1, rooting strong seedlings, etc. to irrigate roots, or fertilize roots in soil, such as fast absorption, or use to increase crop nutrient utilization. Fertilizers such as U.S. chelated eco-complex fertilizers can effectively improve this situation, and farmers can give it a try.
The yellow leaves of the middle and lower parts are mainly yellow and middle leaves of the tomato plants. The yellow leaves gradually appear to develop into yellow leaves throughout the leaves, but mainly yellow veins and veins remain green. As the disease progresses, the leaves gradually become brittle, become brittle, become fragile, and age and fall off, which affects the normal growth of the whole plant, leading to premature aging of plants and tomato fruits.
Incidence rule:
In the middle and lower leaves, it develops gradually from the bottom to the top, in which the plants with weaker growth are more severe.
Disease analysis:
This is a symptom of magnesium deficiency in tomato, which belongs to a physiological disease and can be easily diagnosed as a bacterial disease. However, in this case, there is no lack of magnesium in the soil, but because the root system of the plant is poor in nutrient absorption, or the utilization of nutrient elements is not high, this happens. Mainly this year's climate anomaly. After the tomato colonization, first experienced a period of high temperature, and then experienced a long period of cloudy days, resulting in poor root environment of the tomato, poor root growth, affecting the normal absorption of nutrients in the tomato root; in addition to long-term photosynthetic plants The effect is poor, affecting crops to produce photosynthetic nutrients, and at the same time crops appear yellow (top leaves) due to lack of sufficient light for a long time.
Second, the top leaves yellow: yellow leaves on the top of the tomato, yellow for the entire leaf, the color is light yellow, including leaves and veins, leaves become thinner and smaller.
Disease analysis:
It is a physiological disease that may be related to the lack of iron and zinc in tomatoes.
Solution:
1. Spraying magnesium fertilizer: Spray the foliar fertilizers containing magnesium, such as Green Bole, Green Fenwei and 0.1% magnesium sulfate (that is, a two-to-three sprayer liquid), etc., and spray the lower leaves when spraying.
2. Spray foliar fertilizers containing iron or zinc: spray green fenway 2 or ruthenium green or 0.1% ferrous sulphate (ie 1 2 to 3 sprayer liquids), etc., supplement iron, main spray upper leaves . Note that ferrous sulphate is not suitable for direct application to the soil, otherwise it will damage the soil.
3. Rooting: You can use thiophanate-methyl 600 times as rooting agent, such as Fengshou No.1, rooting strong seedlings, etc. to irrigate roots, or fertilize roots in soil, such as fast absorption, or use to increase crop nutrient utilization. Fertilizers such as U.S. chelated eco-complex fertilizers can effectively improve this situation, and farmers can give it a try.