Timing of Potassium Fertilizer Application for Flue-Cured Tobacco and the Role of Potassium Fertilizer Spray

AbstractThe suitable time to apply potassium fertilizer to flue-cured tobacco is in the late growth stage. It can generally effectively promote the full maturity of the upper leaves of flue-cured tobacco, help promote substance transformation and dry matter accumulation, and can effectively reduce harmful components, keep the sugar-to-nicotine ratio moderate, and help improve cigarette quality.

1. Timing of Potassium Fertilizer Application for Flue-Cured Tobacco

Applying potassium fertilizer in the late growth stage of flue-cured tobacco is relatively suitable. It can effectively promote the full maturity of the upper leaves of flue-cured tobacco, help promote substance transformation and dry matter accumulation, and can effectively reduce harmful components, keep the sugar-to-nicotine ratio moderate, and help improve cigarette quality.

2. Precautions for Fertilizing Flue-Cured Tobacco

1. Balanced fertilization

Single fertilization or excessive fertilization will affect the growth of tobacco plants. Generally, farmyard manure and compound fertilizer are mainly applied, then combined with potassium fertilizer, phosphate fertilizer and various trace elements. Mixed use and balanced fertilization help promote vigorous growth of tobacco plants.

2. Pay attention to spacing

If fertilizer is too close to the root and stem, or the concentration is too high, fertilizer damage such as root rot is likely to occur, and a “root burn” phenomenon may appear. If fertilizer is too far away, it is difficult for the tobacco plant to absorb it. Generally, according to the growth status of the tobacco plant, apply it in holes about 15cm from the stem base of the tobacco plant, then cover with loose, moist soil to ensure the tobacco plant has good aeration.

3. Suit measures to the field

Fertilization needs to be carried out according to soil conditions and the fertility of the tobacco field, and in combination with weather conditions.

4. Small amounts, more times

Fertilization needs to be divided into 2-3 applications to ensure nutrient supply at each growth stage of the tobacco plant. Use small amounts and more times, and fertilize scientifically.

5. Topdressing

Topdressing is carried out in 2 applications. The first is from survival after transplanting to the small rosette stage, that is, 10-15 days after transplanting, combined with intertillage and weeding. The second is before hilling at the rosette stage, when all fertilizer is applied, then intertillage and weeding are carried out, and deep furrows and high hilling are made.

3. Distribution Range of Flue-Cured Tobacco

Flue-cured tobacco originated in South America. It is cultivated in all provinces and regions in the north and south of China. Flue-cured tobacco is a very important agricultural product among China's cash crops. It is the main raw material for cigarette production and one of China's major agricultural exports. The areas where flue-cured tobacco is produced in China are mainly concentrated in provinces such as Yunnan, Henan, Guizhou and Shandong.

4. Curing Methods of Flue-Cured Tobacco

1. Flue-cured tobacco originated in Virginia in the United States, so it is also called Virginia tobacco. Generally, mature tobacco leaves are placed in a curing barn equipped with heating pipes.

2. Then suitable temperature and humidity are provided so that the components in the tobacco leaves undergo biochemical changes. After the leaves turn yellow, they are dried. Therefore, flue-cured tobacco is also called flue-cured tobacco with fire pipes, and it is the main raw material of the cigarette industry.

3. In foreign countries, there is also open-fire flue-cured tobacco, which generally uses burning wood to directly heat the curing barn to complete the curing process. Therefore, this kind of tobacco leaf has a special smoky smell, also called smoked tobacco, and is the raw material for making snuff and chewing tobacco.