Tomato planting techniques: what are the requirements of soil, light, moisture, temperature and fertilization?

Tomato is one of the most widely planted crops in China, and it is also a "side dish" loved by consumers. The planting area is increasing year by year, so in the planting technology of tomato, what are the requirements for soil, light, water, temperature and fertilization?

1. Soil conditions for tomato cultivation

Tomato soil requirements are not too strict, it is best to choose a deep soil layer, good drainage, rich in organic matter of the fertile loam. During the growth period, tomato needs to absorb a lot of nutrients from the soil. To produce 5000 kg of fruit, it is necessary to absorb 33 kg of potassium oxide, 10 kg of nitrogen and 5 kg of phosphorus from the soil. 73% of these elements are distributed in fruits and 27% in stems, leaves, roots and other vegetative organs.

II. Lighting conditions for tomato planting

Tomato is a light-loving short-day crop, but most varieties do not have strict requirements for sunshine and do not need a specific photoperiod, as long as the temperature is suitable, it can be cultivated throughout the year. Generally speaking, the growth is good under the condition of light for 16 hours, and the light saturation point of tomato is 70 000 lux, and the tomato can develop normally at 3 ~ 35000 lux. The light requirements of tomatoes in different growth periods:

① germination period: no light is needed.

② seedling stage: strict requirements for light, lack of light delayed flower bud differentiation, resulting in the increase of flower nodes, the decrease of flower number and the decline of flower bud quality.

③ flowering period: lack of light, easy to cause falling flowers and fruits.

④ fruit period: under strong light, there are many fruits, single fruit is also large, fruit setting rate is low, single fruit weight is reduced, and hollow fruit and gluten rotten fruit are easy to appear.

III. Moisture conditions for tomato planting

The aboveground stems and leaves of tomato are luxuriant, the transpiration is relatively strong, and the transpiration coefficient is about 800, which requires more water. However, the tomato root system is well developed, the water absorption capacity is strong, and the water requirement belongs to the characteristics of semi-drought tolerance, and the air relative humidity is 45% to 50%.

In different growth periods, tomato has different requirements for water: in order to avoid overgrowth and diseases, the soil moisture should not be too high and irrigation should be properly controlled; before the fruit setting of the first inflorescence, the soil moisture is too much, which is easy to cause the overgrowth of the plant and the poor development of the root system, resulting in falling flowers; after the fruit of the first inflorescence is enlarged, the demand for water increases obviously. During the fruit expansion period, the water absorption of each tomato plant is 1 ~ 2 liters per day, according to the soil transpiration, appropriate watering, frequent watering with small water, and the watering interval of 5 ~ 7 days in the full fruit stage.

IV. Temperature conditions for tomato planting

Tomato is a temperature-loving vegetable, generally speaking, it can adapt to tomato growth in the temperature range of 15-35 ℃. The optimum temperature for assimilation was 20-30 ℃. The growth was affected when the air temperature was as high as 33 ℃, stopped growing when it reached 40 ℃, and high temperature damage would occur when it reached 45 ℃.

The growth was slow when the temperature dropped below 10 ℃ and stopped growing at 5 ℃. Tomatoes of minus 1 ℃ and 2 ℃ will freeze to death, but the seedlings which have been hardened by cold tolerance can tolerate minus 2 ℃ for a short time. The optimum ground temperature for tomato growth was 20: 23 ℃. When the local temperature dropped to 6 ℃, the root system stopped growing.

There are some differences in temperature requirements at different developmental stages of tomato.

In the seedling stage of ①, the optimum temperature was 20: 25 ℃ in daytime and 10: 15 ℃ at night. If the temperature is too high or too low in the seedling stage, it is easy to cause weak seedling growth, flower bud differentiation, poor development and poor flower quality, and it is easy to produce falling flowers and fruits in the flowering and fruiting stage.

The flowering stage of ② was sensitive to temperature, and the optimum temperature was 20: 30 ℃ in daytime and 15: 20 ℃ at night. When experiencing low temperature or high temperature above 30 ℃ during flowering, pollen germination and pollen tube elongation are poor, fertilization is poor, and flower and fruit drop is easy to occur.

③ fruiting period: the optimum temperature is 24: 26 ℃ in daytime and 12: 17 ℃ at night.

④ fruit coloring period: the optimum temperature is 20: 25 ℃, and the coloring is poor when the fruit is above 30 ℃.

The growth and development of tomato needs a certain temperature difference between day and night, especially in the fruiting stage. Tomato plants carry out photosynthesis to produce nutrients during the day, and properly reduce the temperature at night, which is beneficial to the transport and accumulation of nutrients, promote the growth of roots, stems, leaves and fruits, and improve yield and quality. Therefore, tomato production in greenhouse in winter is often overgrown due to excessive heating at night.

5. Fertilization conditions for tomato planting

① nitrogen fertilizer: improve crop nutrition running speed, lengthen Internode, lengthen petiole, open large leaf, limit use, overuse crop Internode lengthening, stem thin, petiole super-long, leaf super-large and thin, leaf color light yellow, small fruit in late flowering, slow fruit expansion, affect yield and decrease disease resistance (chicken manure and compound fertilizer must be used less in the old shed). The ability to resist cold is also greatly reduced.

② calcium superphosphate: contains phosphorus and calcium, calcium fertilizer increases crop cell division, blossoms and fruits, flower organ is strong, increases pollination rate, reduces abnormal fruit, when the ground temperature is low, root growth is slow, it is difficult to absorb calcium, it will cause calcium deficiency to appear abnormal fruit, gluten rotten diseased fruit, remedial methods, calcium nitrate is applied in water, and calcium nitrate is sprayed once per ear when the fruit grows to the size of peanut.

③ phosphate fertilizer: promote crop root growth, determine root growth number, reduce the number of phosphorus deficiency main roots, affect crop nutrition transport, early ploughing must use good phosphate fertilizer, deep roots, good transport of nutrients for crops, increase cold and drought resistance, reduce watering times, prevent watering, high humidity, and serious diseases.

④ potash fertilizer: turning the ground should make potassium sulfate, strong straw, expand the fruit, make the fruit good color, bright surface, good hardness, resistant to transportation.

⑤ magnesium fertilizer: increase the chlorophyll content of crops and promote photosynthesis. When magnesium fertilizer is insufficient, the leaves will appear irregular mass macular chlorosis. The distribution of various trace elements is directly related to magnesium.

⑥ zinc fertilizer: accelerate the running speed of crop nutrition, grow faster, and not yellowing shrinking head also play a role in photosynthesis.

⑦ iron fertilizer: after crop absorption, it inhibits the growth of bacteria and forms a protective film on the surface of crop leaves to improve crop disease resistance. Due to the lack of iron, the leaves of the plants were yellowed and the resistance decreased.

⑧ boron fertilizer: increase crop cell division, promote flower bud differentiation, improve crop reproductive growth and vegetative growth balance. Lack of boron, buds do not form or buds are small.

⑨ copper sulfate: improve crop disease resistance, in the crop leaves, straw surface layer to form a wax layer, so that bacteria can not invade.

The use of various elements has a certain amount, and the overuse of each element will affect the absorption of other elements.