Symptoms of nutritional imbalance in tomato

Tomato (Lycopersicon esculentum), also known as tomato, fruit used as a vegetable or fruit, is an important source of vitamin C for humans. Tomato stems trailing or semi-erect, inflorescences cymose or racemose, mature 40 - 50 days after flowering. Tomato is a thermophilic crop, not resistant to frost. The suitable temperature for stem and leaf growth is 20~25℃, and the suitable temperature for fruiting period is 25~28℃ in day and 16~20℃ at night. Night temperature lower than 15℃ or higher than 30℃ will hinder normal fertilization, causing flower drop; flower bud stage below 7℃ to form abnormal fruit; tomato is not sensitive to the length of sunshine, if the temperature is suitable for all seasons can be cultivated. Tomato has wide adaptability to soil. However, waterlogging resistance is weak, and the soil is dry and wet, which is easy to form cracking fruit. Tomato seedlings need to be transplanted after 60~90 days. The planting density is about 2000~4000 plants per mu. Tomato is one of the main vegetables cultivated in protected areas at present. Because tomato blooms and bears fruit at the same time of stem and leaf growth, coordinating vegetative growth and reproductive growth is the key to high yield. Symptoms of nutritional imbalance in tomatoes: Tomato has a higher demand for nutrients throughout its life, and only when all kinds of nutrients are sufficient can the yield and quality of fruit be guaranteed. Nutritional imbalance can lead to symptoms of stunted growth. Nitrogen is an important substance for producing protein and chlorophyll of tomato. When nitrogen is insufficient, the whole plant is short and thin, the leaves are green, the fruit is small and the yield is low; when nitrogen is excessive, the nutrient growth is too vigorous, the fruit setting rate is low, the disease and insect resistance ability is reduced, the fruit is not resistant to extrusion and the preservation period is short. The symptoms of nitrogen excess fruit are similar to those of potassium deficiency. Potassium fertilizer can be used to correct nitrogen excess symptoms. Phosphorus is involved in many key physiological processes of tomato, phosphorus exists in all living cells, phosphorus plays an irreplaceable role in root development and fruit ripening process. Potassium is an important quality element of tomato. Potassium can improve fruit sweetness and reduce invasion of crop diseases. Potassium can improve tomato flowering and fruit setting rate, and also promote flowering, early flowering and ripening, and prolong fruit preservation period. K deficiency tomato lower leaf edge curl, yellow, gray-white spots, potassium deficiency fruit performance as "green back disease". Tomato is easy to suffer from umbilicus rot due to calcium deficiency. At first, the flesh near the umbilicus appears water-stained necrosis, the diseased tissue collapses, then blackens, shrinks and sinks, and generally does not drop fruit. Tomato is sensitive to magnesium deficiency, chlorosis occurs between lower veins of magnesium deficiency, leaf margin becomes orange, red, purple and other colors, fruit also fades from red to light orange, pulp viscosity decreases. Chlorosis of veins, reddening of petioles and stems, shortening of internodes and reduction of leaves due to sulfur deficiency. The whole plant is pale green or yellowish green. Manganese deficiency in tomato leaves between the green pale yellow veins, veins remain green, veins more clear, severe manganese deficiency has gray or brown spots. Tomato iron deficiency first appeared yellow whitening in the terminal bud and new leaves, green along the veins, thin leaves, generally no browning, necrosis phenomenon, leaf base also appeared gray-yellow spots. Tomato leaves were clustered in zinc deficiency, new leaves appeared yellow spots, yellow spots gradually extended to the whole leaf, but also easy to infect virus diseases. Tomato was sensitive to copper deficiency and showed apical chlorosis. Rust appeared on the surface of tomato fruit due to boron deficiency; the terminal bud of tomato with boron deficiency stopped growing pericarp and pulp necrosis, cork, flower but not fruit, and rust appeared on the surface of fruit easily. The leaves of tomato with Mo deficiency were yellow and curly at true leaf stage, the new leaves were spotted, the green part was arched upward, the leaflets were rolled up, and the leaf tips and leaf margins of the last leaflets were shriveled and died. Chlorine deficiency inhibited the growth of tomato, and the leaf tip wilted and narrowed, and the root shortened and thickened. According to the external symptoms, whether tomato is deficient and its degree can be preliminarily judged. Potassium is an important quality element of tomato. Potassium can improve fruit sweetness and reduce invasion of crop diseases. Potassium can improve tomato flowering and fruit setting rate, and also promote flowering, early flowering and ripening, and prolong fruit preservation period. K deficiency tomato lower leaf edge curl, yellow, gray-white spots, potassium deficiency fruit performance as "green back disease". Tomato is easy to suffer from umbilicus rot due to calcium deficiency. At first, the flesh near the umbilicus appears water-stained necrosis, the diseased tissue collapses, then blackens, shrinks and sinks, and generally does not drop fruit. Tomato leaves were clustered in zinc deficiency, new leaves appeared yellow spots, yellow spots gradually extended to the whole leaf, but also easy to infect virus diseases. Chlorosis of veins, reddening of petioles and stems, shortening of internodes and reduction of leaves due to sulfur deficiency. The whole plant is pale green or yellowish green. Tomato iron deficiency first appeared yellow whitening in the terminal bud and new leaves, green along the veins, thin leaves, generally no browning, necrosis phenomenon, leaf base also appeared gray-yellow spots. Nitrogen excess nutrition of tomato results in over-vigorous growth, low fruit setting rate, decreased ability of disease and insect resistance, short shelf life of fruit with stress intolerance, symptoms of nitrogen excess fruit are similar to potassium deficiency, and potassium fertilizer can be used to correct nitrogen excess symptoms. Manganese deficiency in tomato leaves between the green pale yellow veins, veins remain green, veins more clear, severe manganese deficiency has gray or brown spots. Rust appeared on the surface of tomato fruit due to boron deficiency; the terminal bud of tomato with boron deficiency stopped growing pericarp and pulp necrosis, cork, flower but not fruit, and rust appeared on the surface of fruit easily. Tomato is sensitive to magnesium deficiency, chlorosis occurs between lower veins of magnesium deficiency, leaf margin becomes orange, red, purple and other colors, fruit also fades from red to light orange, pulp viscosity decreases. The leaves of tomato with Mo deficiency were yellow and curly at true leaf stage, the new leaves were spotted, the green part was arched upward, the leaflets were rolled up, and the leaf tips and leaf margins of the last leaflets were shriveled and died.