Excuse me, how do cigarettes grow?

1. Environmental conditions for tobacco growth

1. Temperature: Tobacco is a thermophilic crop, which can grow in the range of 8-38℃ above ground. The optimum temperature for growth and development is 25-28℃, and when it is 2-3c below zero, the tobacco plant will die. Underground parts can grow at 7-43℃, but the suitable temperature is 31℃. The optimum temperature for seed germination is 24-29℃, the low temperature is 7.5—1C, and the high temperature is 35C. When the temperature is lower than 7.5℃, the seed germination process stops; Above 3℃, the germination process is slow; If the temperature exceeds 35℃, the germinated seeds will gradually lose their vitality. Generally, the transplanting period of tobacco should be after the late frost, the temperature should not be lower than 1℃, and the ideal daily average temperature of leaf maturity should be about 24C for 3 days, so that high-quality tobacco leaves can be produced.

2. Moisture: Generally, water is needed in the early stage of growth, with more in the middle stage and less in the later stage. It is advisable to keep the soil moisture at about 7% of the field capacity in the seedbed stage, and stop the water supply 1-15 days before transplanting to harden the seedlings. Transplanted to the seedling stage, the leaf transpiration is small, and the average daily water consumption is 3.5-6.4 mm. The average daily water consumption is 6.6-7.9 mm from seedling returning to tree-clumping stage, and it is appropriate to keep the soil moisture at 6% of the field capacity; Below 4%, the growth will be hindered, while above 8%, the root growth will be poor, which is unfavorable to the later growth. The average daily water consumption is 7.1-8.5 mm from the fruiting stage to the budding stage, and it is appropriate to keep the soil moisture at 8% of the field capacity. If there is water shortage at this stage, the growth will be hindered, and if there is long-term drought, early flowering or early drying will occur. From budding to maturity, the average daily water consumption is 5.5-6.1 mm, and the soil moisture should be kept at 6% of the field capacity, and the moisture should be slightly less at this stage, which can improve the quality of tobacco leaves; If there is too much soil moisture, it is easy to delay maturity and reduce quality.

3. Sunshine: Tobacco always needs enough sunshine, but most varieties are not strict about the length of sunshine. Flue-cured tobacco requires sufficient sunlight in the growth period, but it is not very intense. It is appropriate to have 8-1 hours of sunlight every day, especially in the mature period. Adequate sunlight is a necessary condition for producing high-quality tobacco leaves. Sunny sunny days with short-wave components are beneficial to improve the quality of tobacco leaves.

4. Soil: Although tobacco can grow on many types of soil, the requirements for growing high-quality tobacco are strict. Red soil is the best, followed by red loess, sandy soil and mixed soil, while tidal loessial soil (black soil) is poor.

5. Weather phenomenon: gale and hail weather are more harmful to tobacco leaves than any other crops, which may bring serious losses whether in seedbed or field. Therefore, tobacco cannot be planted in areas where strong winds and hail often occur during the tobacco growth period.

2. Cultivation and management of tobacco

1. Seedling raising: Tobacco seeds should be exposed to sunlight at 15-2℃ for 2-3 days before germination.

To cultivate strong seedlings:

First, adopt the new technology of double-layer film paper tube seedling raising;

the second is to prepare nutrient soil;

Third, timely early sowing and early transplanting can increase yield by 2% and quality by 25%. ;

fourth, seedbed management, because the temperature is low when sowing, it is vulnerable to low temperature, so it should be adjusted in time according to the requirements of temperature and humidity for tobacco seedling growth.

2. Transplanting: timely and early planting is the key to produce high-quality tobacco. Planting tobacco with plastic film mulching can not only increase temperature and keep moisture, but also improve the drought and waterlogging resistance of tobacco plants and prevent tobacco black storm. If it rains thoroughly before transplanting, it can be covered with film in time after the rain to keep moisture and raise temperature. If there is no rain, you should bring water from the soles of your feet when planting tobacco, and cover the tobacco with plastic film tightly after planting tobacco (if you plant tobacco before and after Qingming, because the temperature is low, you can cover the film first and then expose the seedlings, and then cut the plastic film when the temperature is stable, take out the tobacco seedlings and seal the film at the roots to prevent water loss).

3. Field management:

① Appropriate fertilization: base fertilizer is the main fertilizer, and new balanced fertilization technology is adopted. When fertilizer deficiency is found in the middle and late stage, foliar spraying is used for topdressing.

② timely irrigation and drainage: under the drought situation in the critical period of tobacco water demand, spraying irrigation once or twice can increase the yield by 8.1-43.1% and improve the quality. If the tobacco field is waterlogged for 1-2 days, the yield will be reduced by 47.8-65%. Pay attention to ditch cleaning and drainage in low-lying tobacco fields or rainy seasons.

③ Pay attention to intertillage and soil cultivation: intertillage in time under drought conditions is of great significance for water conservation. Timely intertillage after rain can reduce soil moisture, increase soil permeability, increase ground temperature and promote root growth. Tillage can also eliminate weeds and reduce pests and diseases. Combined with intertillage and timely soil cultivation, it can promote new roots, expand the ability to absorb water and fertilizer, be beneficial to drainage and waterlogging prevention, and enhance the ability to resist drought, wind and lodging.

④ timely topping to remove branches: topping should generally be finished in two times according to the number of leaves left, so as to promote the tobacco plants to be neat, grow and yellow uniformly, which is beneficial to baking. Branches should be cleaned in time.

⑤ Strengthen pest control: give priority to prevention, and combine chemical control with artificial killing.