In tobacco production, the soil environment has an important influence on the growth and production quality of tobacco. The requirements of tobacco growth on soil characteristics are mainly as follows: The soil texture is generally loose topsoil and compact soil is more suitable. The growth and development of tobacco, because the soil water retention capacity and drainage and ventilation performance are better, which is conducive to the growth of tobacco
Sandy soil is resistant to waterlogging but not drought, and has poor water and fertilizer retention capacity. Although tobacco plants can still grow in the early and middle stages, they are prone to defertilization in the later stages and the output quality is poor. The soil has a heavy texture, poor drainage and aeration performance, ground temperature should not rise, and nutrient supply is slow, so that tobacco plants grow slowly in the early and mid-term, and make money later. Some studies believe that the soil texture in high-quality tobacco areas should be sandy loam to medium loam, with a soil bulk density ranging from 1.1 to 1.4 grams per cubic centimeter, a total soil porosity ranging from 47.3% to 56.9%, and a field water holding capacity of the soil in the range 23.9% ~28.9%.
The level of soil fertility has a great influence on the yield and quality of tobacco, and different types of tobacco have different requirements for soil fertility. Studies have shown that flue-cured tobacco requires moderate soil organic matter content, oriental tobacco requires poor soil and low nitrogen content, and burley tobacco requires fertile soil. If the soil organic matter content and fertility are too low, it will cause flue-cured tobacco to grow during the growth process. Due to lack of nutrients, the growth is weak, the plants are short, the leaves are small and thin, and the yield and quality are poor; if
The soil fertility is too high, the flue-cured tobacco produced has thick leaves, thicker main veins, increased protein and nitrogenous compounds in tobacco, and poor quality.
The most suitable soil pH for tobacco plant growth is 5.5~7.0. The pH value of the rhizosphere of tobacco plants affects the growth and development, yield and quality of tobacco, mainly by affecting the growth of tobacco roots and the status, quantity and availability of nutrients in the soil. When the soil pH value is too low, the soil will be strongly acidic, which is not conducive to the growth of tobacco; when the soil pH value is too high, it will affect the tobacco’s absorption of iron, pickaxe, and phosphorus, thus presenting symptoms of nutrient deficiency. In fact, tobacco roots have a strong ability to self-adjust the pH of the rhizosphere. Even if the soil pH is not in the optimum range for tobacco plant growth, tobacco has the ability to adjust the pH of the rhizosphere to an appropriate range.