What Causes Poor Color Development in Tomatoes? Detailed Explanation of Prevention and Control Methods
Tomato is one of the common vegetables in our lives. When unripe, it is green, and when ripe, it is red. As it gradually matures, the green gradually turns red. However, certain elements can cause poor coloring in tomatoes, resulting in a phenomenon where green and yellow meet. So what causes this? How should it be prevented and controlled? Let's take a look at the detailed introduction.
1. Temperature too low
Tomato plants contain chlorophyll and carotenoids, and their color change is controlled by these two pigments. When the low temperature is below 16°C, carotene will be inhibited, and when it is below 24°C, lycopene formation will be inhibited, which leads to poor coloring. This is generally more serious in greenhouses, and may also be caused by a large difference between day and night temperatures.
Prevention and control methods: When entering a low-temperature period, tomatoes show poor coloring because the temperature does not meet the requirements for lycopene formation. A ripening agent can be sprayed before harvest to promote earlier marketing. However, note that the agent should not be used too early, so as to avoid stiff fruit; the agent should not be too concentrated, so as to avoid yellowing leaves and symptoms of phytotoxicity; each plant should not have too many fruits treated for ripening, so as to avoid phytotoxicity to the plant; the solution must not be sprayed on the leaves, as it will cause the leaves to yellow and wither.
2. Improper fertilization
During the coloring stage of tomatoes, if too much nitrogen fertilizer is applied, the chlorophyll in tomatoes will increase, causing chlorophyll decomposition to be delayed and affecting the formation of lycopene and carotene. In addition, nitrogen deficiency and potassium deficiency can lead to yellow fruit; boron deficiency can lead to green fruit.
Prevention and control methods: For the later stage of tomato growth, the amount of nitrogen fertilizer applied should be controlled. If the planting soil is deficient in nitrogen, a complete-formula fertilizer can be used, but nitrogen fertilizer should not be applied alone. When the plant lacks certain elements, foliar fertilizer spraying can be used to supplement what the plant needs.
3. Planting too densely
The coloring of tomatoes has a great relationship with light. If the planting density is too high, the leaves between plants will shade each other, so the fruit cannot get sufficient light, resulting in poor coloring and the phenomenon of green-shouldered fruit.
Prevention and control methods: The planting density should be controlled to promote good field ventilation and light penetration. In the later stage, branches and leaves can be pruned to maintain air and light penetration, so that the fruit has sufficient light conditions and coloring is promoted.
4. Other reasons
When the fruit lacks water, when too many fruits set cause insufficient nutrient supply or weakened root absorption capacity, or when the soil is compacted and salinized, all of these can lead to poor coloring in tomatoes.
Prevention and control methods: During the fruit expansion stage, water timely when there is drought, but note that it is not suitable to water too much at one time; keeping the soil moist is enough. When too many fruits have set, fruit thinning measures can be taken. When root absorption capacity is weakened, foliar fertilizer spraying can be used to maintain nutrients, and more organic fertilizer can be applied to improve soil structure, so as to prevent it from becoming compacted and salinized.
The above is an introduction to the causes of poor color development in tomatoes and the prevention and control methods. We hope it can help you. If you want to learn more related knowledge, please follow us.