What factors affect the content of anthocyanins in black tomato?

The content of anthocyanins in black tomato was affected by the following factors:
First, variety differences
Different varieties of black tomatoes have different anthocyanin content at the genetic level. This is because genes control the expression of enzymes involved in anthocyanin synthesis in plants. For example, some specially bred varieties with high anthocyanin content may be more active in the key genes controlling anthocyanin synthesis, and the anthocyanin content of these varieties will be significantly higher than that of ordinary varieties.
Second, planting environment
Light: Light is an important environmental factor affecting anthocyanin synthesis of black tomato. Sufficient light is conducive to anthocyanin accumulation. Light can activate the photoreceptors in black tomato plants, and then regulate the expression of genes related to anthocyanin synthesis. When black tomatoes grow in a sunny environment, the pathways related to anthocyanin synthesis are strengthened, resulting in an increase in anthocyanin content. On the contrary, in the environment of insufficient light, such as long-term shade conditions, the synthesis of anthocyanins will be inhibited, and the content will be reduced.
Temperature: Temperature also has a significant effect on the anthocyanin content of black tomato. The suitable temperature range is conducive to the synthesis of anthocyanins. Generally speaking, in the environment with a large temperature difference between day and night, the anthocyanin accumulation of black tomato is more. Higher daytime temperature is conducive to photosynthesis and provides sufficient material basis for anthocyanin synthesis. Lower night temperatures can reduce consumption such as respiration, making more photosynthates available for anthocyanin synthesis. For example, black tomatoes grown in mountains where the temperature difference between day and night can reach 10-15 ° C tend to have higher anthocyanin content than those grown in plains where the temperature is more constant.
Soil conditions: soil fertility, pH and so on affect the anthocyanin content of black tomato. Soil fertility, especially rich in phosphorus, potassium and other elements, can promote the synthesis of anthocyanins. Phosphorus is an important element in energy metabolism and nucleic acid synthesis in plants, and potassium can regulate the physiological metabolic process of plants. Black tomatoes grown in acidic soil with the right pH may have higher levels of anthocyanins. This is because in an acidic environment, the activity of some enzymes involved in anthocyanin synthesis is enhanced.
Iii. Maturity
As black tomatoes mature, the content of anthocyanins changes. Under normal circumstances, when the black tomato is not fully ripe, the anthocyanin content will gradually increase, and the content is relatively stable when it reaches the mature stage. For example, in the process of black tomato from the green fruit stage to the color transformation stage, and then to full maturity, the anthocyanin content first increased rapidly, and when the fruit color became completely black and the texture became soft, the anthocyanin content reached a higher level. However, if the fruit is overripe, it may be due to some physiological changes and the decomposition of the substance, resulting in a slight decrease in anthocyanin content.
Iv. Planting management measures
Fertilization: Reasonable fertilization strategy can affect anthocyanin content of black tomato. The synthesis of anthocyanins could be promoted by applying appropriate amount of organic fertilizer and fertilizer containing trace elements. For example, the application of fertilizers containing trace elements such as boron and molybdenum, which can be used as cofactors of related enzymes in the synthesis process of anthocyanin, enhance the activity of the enzyme, thereby improving the yield of anthocyanin.
Irrigation: Irrigation method and amount of water also affect anthocyanin content. Moderate drought stress can stimulate black tomato plant to produce stress response and increase anthocyanin synthesis to a certain extent. However, if the drought is too severe, it will cause damage to the plant, but it is not conducive to the accumulation of anthocyanins. Reasonable irrigation can maintain the water balance of plants and ensure the normal process of anthocyanin synthesis.