Special mixed fertilizer for flue-cured tobacco and use method thereof

Abstract

The invention discloses a special mixed fertilizer for flue-cured tobaccos and a use method thereof, the flue-cured tobaccos per mu comprise the following components by weight: 12-16 kg of urea with a nitrogen content of 45-47%, 59-71 kg of calcium superphosphate with a phosphorus content of 11-13% and 29-36 kg of potassium sulfate with a potassium oxide content of 49-51%, and the use method of the mulched flue-cured tobaccos per mu comprises the following steps of: adding the urea, the calcium superphosphate and the potassium sulfate to the mulched flue-cured tobaccos per mu; comprising the following steps: applying 2.5-5.5 kg of urea in the special flue-cured tobacco mixed fertilizer within 10 days after tobacco planting, applying 4.5-7.5 kg of potassium sulfate in the special flue-cured tobacco mixed fertilizer within 19-21 days after tobacco planting, uniformly mixing the rest of urea, calcium superphosphate and potassium sulfate, and applying after transplanting. Comprising the following steps: applying 3.5-6.5 kg of urea in the special flue-cured tobacco mixed fertilizer within 10 days after tobacco planting, applying 6.5-8.5 kg of potassium sulfate in the special flue-cured tobacco mixed fertilizer within 19-21 days after tobacco planting, uniformly mixing the rest of urea, calcium superphosphate and potassium sulfate, and applying after transplanting. Therefore, precise adaptive fertilization can be realized, the growth and quality of tobacco leaves are improved, and the use flexibility is enhanced.

Description

Technical Field

[0001] This invention relates to the field of tobacco cultivation, specifically to a special blended fertilizer for flue-cured tobacco and its application method. Background Technology

[0002] In the field of flue-cured tobacco cultivation technology, the ratio, application amount, and fertilization method of compound fertilizer must be adapted to soil conditions, planting patterns, and the fertilizer requirements of flue-cured tobacco during its growth period. This is a key technical prerequisite for ensuring the normal growth of flue-cured tobacco and promoting the formation of high-quality tobacco leaves.

[0003] In existing flue-cured tobacco cultivation, the specialized fertilizer system consists of a combination of specialized base fertilizer, specialized topdressing fertilizer, and specialized seedling fertilizer. Generally, fertilizers with a uniform formula are applied according to a fixed standard, namely 50 kg of specialized base fertilizer, 15 kg of specialized topdressing fertilizer, and 2.5 kg of specialized seedling fertilizer per mu. The final total content of pure nitrogen, phosphorus, and potassium per mu is 7.3 kg, 6.35 kg, and 17.25 kg, respectively, with a nitrogen-phosphorus-potassium ratio of 1:0.84:2.28. Moreover, this technical solution does not differentiate between soil fertility levels, mulched and non-mulched planting modes, nor does it adjust fertilization strategies according to the different fertilizer requirements of flue-cured tobacco at different growth stages. All plots implement a uniform fertilization standard.

[0004] It is not difficult to see that the existing specialized fertilizer system uses fixed and uniform fertilizer formulas and application standards, which are not adapted to soil fertility levels, planting patterns and the fertilizer requirements of flue-cured tobacco at different growth stages. This makes it impossible to achieve precise nutrient supply to flue-cured tobacco, and thus makes it difficult to meet the technical requirements for high-quality tobacco leaf production. Summary of the Invention

[0005] The present invention aims to at least partially solve the technical problems in the above-mentioned technologies.

[0006] Therefore, this invention discloses a special blended fertilizer for flue-cured tobacco, which, by weight, comprises the following for each acre of flue-cured tobacco:

[0007] 12-16 kg of urea with a nitrogen content of 45-47%, 59-71 kg of superphosphate with a phosphorus content of 11-13%, and 29-36 kg of potassium sulfate with a potassium oxide content of 49-51%.

[0008] It should be noted that the application method for mulched tobacco per acre includes the following steps:

[0009] For the first top dressing, apply 2.5 to 5.5 kg of urea from the flue-cured tobacco-specific blended fertilizer within 10 days after planting.

[0010] The second top dressing should be applied 19-21 days after planting, using 4.5-7.5 kg of potassium sulfate from the flue-cured tobacco-specific blended fertilizer.

[0011] For base fertilizer application, mix the remaining urea, superphosphate, and potassium sulfate evenly and apply after transplanting.

[0012] It should be noted that the application method for non-mulched tobacco per acre includes the following steps:

[0013] For the first top dressing, apply 3.5 to 6.5 kg of urea from the flue-cured tobacco-specific blended fertilizer within 10 days after planting.

[0014] The second top dressing should be applied 19-21 days after planting, using 6.5-8.5 kg of potassium sulfate from the aforementioned flue-cured tobacco-specific blended fertilizer.

[0015] For base fertilizer application, mix the remaining urea, superphosphate, and potassium sulfate evenly and apply after transplanting.

[0016] The flue-cured tobacco-specific blended fertilizer and its application method disclosed in this invention have at least the following beneficial effects:

[0017] (1) By optimizing the content range and ratio of urea, superphosphate and potassium sulfate in compound fertilizer, and adapting it to different soil fertility, planting patterns and fertilizer requirements of flue-cured tobacco during its growth period, the problem of the existing fixed formula being unable to accurately supply fertilizer has been solved.

[0018] (2) By using reasonable fertilizer combinations and application schemes, the different nutrient requirements of flue-cured tobacco at different growth stages can be met, promoting root development and aroma accumulation, and avoiding growth problems caused by nutrient imbalance.

[0019] (3) The dosage and topdressing strategy can be flexibly adjusted according to the soil and planting mode, and can be adapted to the fertilizer requirements of different crops, which has strong flexibility.

[0020] Additional features and advantages of this invention will be set forth in the description which follows, or may be learned by practicing the invention. Detailed Implementation

[0021] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0022] The following describes the special blended fertilizer for flue-cured tobacco disclosed in this invention and its application method.

[0023] A special blended fertilizer for flue-cured tobacco, comprising, by weight, the following per acre of flue-cured tobacco:

[0024] 12-16 kg of urea with a nitrogen content of 45-47%, 59-71 kg of superphosphate with a phosphorus content of 11-13%, and 29-36 kg of potassium sulfate with a potassium oxide content of 49-51%.

[0025] It should be noted that the application method for mulched tobacco per acre includes the following steps:

[0026] For the first top dressing, apply 2.5 to 5.5 kg of urea from a special blended fertilizer for flue-cured tobacco within 10 days after planting.

[0027] The second top dressing should be applied 19-21 days after planting, using 4.5-7.5 kg of potassium sulfate from a special blended fertilizer for flue-cured tobacco.

[0028] For base fertilizer application, mix the remaining urea, superphosphate, and potassium sulfate evenly and apply after transplanting.

[0029] It should be noted that the application method for non-mulched tobacco per acre includes the following steps:

[0030] For the first top dressing, apply 3.5 to 6.5 kg of urea from a special blended fertilizer for flue-cured tobacco within 10 days after planting.

[0031] The second top dressing should be applied 19-21 days after planting, using 6.5-8.5 kg of potassium sulfate from a special blended fertilizer for flue-cured tobacco.

[0032] For base fertilizer application, mix the remaining urea, superphosphate, and potassium sulfate evenly and apply after transplanting.

[0033] Example 1

[0034] For soils with high fertility, this special blended fertilizer for flue-cured tobacco, when applied per acre of flue-cured tobacco by weight, includes:

[0035] 13.04 kg of urea with a nitrogen content of 46%, 60 kg of superphosphate with a phosphorus content of 12%, and 30 kg of potassium sulfate with a potassium oxide content of 50%.

[0036] Specifically, fertile soils naturally have ample reserves of nitrogen, phosphorus, and potassium. This formulation precisely controls the amount of urea used, preventing excessive nitrogen from causing excessive vegetative growth, thick leaves, and reduced combustibility in flue-cured tobacco. The selected superphosphate has a phosphorus content of 12%, as water-soluble phosphorus is easily absorbed by the tobacco roots, meeting the phosphorus requirements from the seedling stage to the vigorous growth phase, promoting root development and flower bud differentiation. The potassium sulfate, being chlorine-free, aligns with the tobacco's aversion to chlorine, and its 50% potassium oxide content fully meets the tobacco's potassium requirements, contributing to the accumulation of aroma compounds in the leaves.

[0037] The method for applying plastic film to flue-cured tobacco per acre includes the following steps:

[0038] For the first top dressing, apply 3 kg of urea from the flue-cured tobacco-specific blended fertilizer within 10 days after planting.

[0039] The second top dressing should be applied within 20 days after planting, using 5 kg of potassium sulfate from a special blended fertilizer for flue-cured tobacco.

[0040] For base fertilizer application, mix the remaining urea, superphosphate, and potassium sulfate evenly and apply after transplanting.

[0041] Specifically, within 10 days after planting, tobacco seedlings are in a recovery period with weak root absorption capacity. Applying 3 kg of urea at this time provides a readily available nitrogen source that can be quickly absorbed by the seedlings, promoting stem and leaf expansion and root recovery. Under mulch film, the soil retains moisture and fertilizer well, requiring only a small amount of topdressing to meet the needs and avoid nitrogen leaching and waste. Twenty days after planting, tobacco enters the transition from the root elongation stage to the vigorous growth stage, and the demand for potassium begins to rise. Applying 5 kg of potassium sulfate can enhance the toughness of plant cell walls, improve resistance to lodging and pests, and promote the transport of photosynthetic products to the leaves. Base fertilizer should be mechanically stirred for 3-5 minutes until uniform to avoid excessively high local nutrient concentrations. After transplanting, apply the fertilizer in 15-20 cm deep trenches along the planting rows, cover with soil, and compact to prevent fertilizer volatilization under mulch film.

[0042] The application method for non-mulched tobacco per acre includes the following steps:

[0043] For the first top dressing, apply 4 kg of urea from the flue-cured tobacco-specific blended fertilizer within 10 days after planting.

[0044] The second top dressing should be applied within 20 days after planting, using 6 kg of potassium sulfate from a special blended fertilizer for flue-cured tobacco.

[0045] For base fertilizer application, mix the remaining urea, superphosphate, and potassium sulfate evenly and apply after transplanting.

[0046] Specifically, non-mulched tobacco plants lack soil mulch protection, resulting in faster soil moisture evaporation and a higher risk of nutrient leaching compared to mulched plants. Therefore, the amount of urea used in the first topdressing should be appropriately increased to ensure a continuous nitrogen supply during the seedling establishment period and prevent a decrease in fertilizer utilization due to water loss. Potassium sulfate should be applied 20 days after planting to replenish potassium lost through soil leaching, meeting the potassium requirements of tobacco during the early vigorous growth stage and promoting leaf cell division and expansion. The base fertilizer should be mixed and applied in holes. Dig holes 12-15 cm deep, 10-15 cm away from each tobacco plant on both sides, evenly fill the holes with the mixed fertilizer, and cover with soil, keeping a certain distance away from the roots to prevent root burn. Simultaneously, cultivate and loosen the soil to break up soil compaction and improve root absorption efficiency.

[0047] Regarding the remaining technical details of this embodiment

[0048] Example 2

[0049] For moderately fertile soils, this flue-cured tobacco-specific blended fertilizer, per acre of flue-cured tobacco, by weight, includes:

[0050] 14.13 kg of urea with a nitrogen content of 46%, 65 kg of superphosphate with a phosphorus content of 12%, and 32.5 kg of potassium sulfate with a potassium oxide content of 50%.

[0051] Specifically, the natural supply of nitrogen, phosphorus, and potassium in moderately fertile soils falls between that of high and low fertility soils. Therefore, the amount of urea used should be appropriately increased compared to high-fertility soils to meet the nitrogen requirements of flue-cured tobacco throughout its entire growth period and prevent nutrient deficiency in the later stages. The amount of superphosphate used should be increased accordingly to compensate for insufficient phosphorus reserves in the soil and promote deep root development and nutrient transformation in flue-cured tobacco. The amount of potassium sulfate used should be moderately increased to provide sufficient potassium for flue-cured tobacco. Overall, the nitrogen, phosphorus, and potassium ratio is in line with the fertilizer requirements of flue-cured tobacco in moderately fertile soils, which require sufficient nitrogen, stable phosphorus, and adequate potassium.

[0052] The method for applying plastic film to flue-cured tobacco per acre includes the following steps:

[0053] For the first top dressing, apply 4 kg of urea from the flue-cured tobacco-specific blended fertilizer within 10 days after planting.

[0054] The second top dressing should be applied within 20 days after planting, using 6 kg of potassium sulfate from a special blended fertilizer for flue-cured tobacco.

[0055] For base fertilizer application, mix the remaining urea, superphosphate, and potassium sulfate evenly and apply after transplanting.

[0056] In medium-fertility soil under plastic film mulch, the nitrogen requirement for flue-cured tobacco during the seedling establishment period is slightly higher than in highly fertile soil. The amount of urea used in the first topdressing should be appropriately increased to promote rapid seedling growth and establish a high-yielding plant structure. The mulch's fertilizer-retaining effect reduces nitrogen loss and prevents excessive vegetative growth. Twenty days after planting, flue-cured tobacco enters its vigorous growth phase, significantly increasing its potassium demand. At this time, topdressing with potassium sulfate provides sufficient potassium, promoting chlorophyll synthesis in leaves, enhancing photosynthetic efficiency, and improving the combustibility and aroma purity of the tobacco leaves. Before mixing with the base fertilizer, the raw materials should be crushed to a particle size of less than 5 mm to avoid large pieces affecting uniformity. After transplanting, choose between strip application or hole application depending on the row spacing; apply in strips when the row spacing is large and in holes when the row spacing is small. After application, cover with soil and compact to ensure full contact between the fertilizer and the soil.

[0057] The application method for non-mulched tobacco per acre includes the following steps:

[0058] For the first top dressing, apply 5 kg of urea from the flue-cured tobacco-specific blended fertilizer within 10 days after planting.

[0059] The second top dressing should be applied within 20 days after planting, using 7 kg of potassium sulfate from a special blended fertilizer for flue-cured tobacco.

[0060] For base fertilizer application, mix the remaining urea, superphosphate, and potassium sulfate evenly and apply after transplanting.

[0061] Specifically, in non-mulched, moderately fertile soils, the risk of nutrient volatilization and leaching is higher than in mulched soils. Therefore, the amount of urea used in the first topdressing should be appropriately increased compared to mulched soils to ensure sufficient nitrogen supply during the seedling establishment period and prevent fertilizer incomplete dissolution due to water evaporation. The amount of potassium sulfate used in the second topdressing should be increased accordingly to address the urgent potassium demand of flue-cured tobacco during its vigorous growth period, compensate for the weak potassium retention capacity of non-mulched soils, promote the conversion of starch to sugar in tobacco leaves, and improve flavor. After applying the base fertilizer, cover it with a shallow layer of soil (5-8 cm) to reduce fertilizer volatilization loss. If the soil moisture content is insufficient after topdressing, timely artificial irrigation or drip irrigation is necessary, with the water level ideally moistening the soil to a depth of 10-15 cm to promote fertilizer dissolution and absorption, ensuring effective nutrient acquisition by the flue-cured tobacco.

[0062] Example 3

[0063] For soils with low fertility, this special blended fertilizer for flue-cured tobacco, by weight per acre of flue-cured tobacco, includes:

[0064] 15.22 kg of urea with a nitrogen content of 46%, 70 kg of superphosphate with a phosphorus content of 12%, and 35 kg of potassium sulfate with a potassium oxide content of 50%.

[0065] Specifically, soils with low fertility are deficient in nitrogen, phosphorus, and potassium, failing to meet the normal growth requirements of flue-cured tobacco. Therefore, the amount of urea used is further increased compared to medium-fertility soils to ensure an uninterrupted nitrogen supply throughout the entire growth period from seedling establishment to maturity, preventing stunted growth and thin leaves. The amount of superphosphate used is significantly increased to fully replenish soil phosphorus, promote deep root development in flue-cured tobacco, improve the plant's adaptability to poor soil, and provide sufficient phosphorus during the flowering and fruiting period. The amount of potassium sulfate used is further increased to fully meet the potassium-loving characteristics of flue-cured tobacco and compensate for the severe potassium deficiency in the soil.

[0066] The method for applying plastic film to flue-cured tobacco per acre includes the following steps:

[0067] For the first top dressing, apply 5 kg of urea from the flue-cured tobacco-specific blended fertilizer within 10 days after planting.

[0068] The second top dressing should be applied within 20 days after planting, using 7 kg of potassium sulfate from a special blended fertilizer for flue-cured tobacco.

[0069] For base fertilizer application, mix the remaining urea, superphosphate, and potassium sulfate evenly and apply after transplanting.

[0070] Specifically, while mulching reduces nutrient loss in low-fertility soils, the soil itself has limited nutrient reserves. Therefore, the amount of urea used for the first topdressing should be appropriately increased compared to planting under mulch in medium-fertility soils. This provides sufficient nitrogen for seedlings during the establishment period, promoting rapid stem and leaf growth and compensating for soil fertility deficiencies. Twenty days after planting, tobacco enters its vigorous growth phase, reaching peak potassium demand. At this time, topdressing with potassium sulfate provides sufficient potassium, enhancing plant resistance, promoting leaf cell division and swelling, and laying the foundation for high-quality tobacco leaves. The base fertilizer should be mixed in three stages, allowing it to stand for 5 minutes after each mixing to ensure even distribution of components. The application depth should be controlled at approximately 20 cm to avoid direct contact with the roots. Simultaneously, the moisture-retaining effect of the mulch reduces fertilizer crystallization caused by water evaporation, improving fertilizer utilization.

[0071] The application method for non-mulched tobacco per acre includes the following steps:

[0072] For the first top dressing, apply 6 kg of urea from the flue-cured tobacco-specific blended fertilizer within 10 days after planting.

[0073] The second top dressing should be applied within 20 days after planting, using 8 kg of potassium sulfate from a special blended fertilizer for flue-cured tobacco.

[0074] For base fertilizer application, mix the remaining urea, superphosphate, and potassium sulfate evenly and apply after transplanting.

[0075] Specifically, in low-fertility soils without plastic film mulching, the risk of nutrient loss and volatilization is highest. The amount of urea used in the first topdressing should be appropriately increased compared to plastic film mulching to ensure sufficient nitrogen supply during the seedling establishment period, preventing stunted growth, weak seedlings, and yellowing. The amount of potassium sulfate used in the second topdressing should be further increased to provide sufficient potassium for the vigorous growth stage of flue-cured tobacco, promoting the synthesis and accumulation of aroma substances in the leaves, while also enhancing the plant's drought resistance and alleviating growth inhibition caused by water shortage in low-fertility soils. After applying the base fertilizer, timely cultivation and covering with soil to a thickness of 8-10 cm are necessary to reduce fertilizer volatilization. If drought occurs after topdressing, timely irrigation is required, using furrow irrigation to avoid flooding and nutrient leaching. Field inspections should be conducted 10 days after topdressing; if nutrient deficiency symptoms are found, a small amount of foliar fertilizer can be applied appropriately to ensure normal growth of the flue-cured tobacco.

[0076] In summary, the flue-cured tobacco-specific blended fertilizer and its application method disclosed in this invention have at least the following beneficial effects:

[0077] (1) By optimizing the content range and ratio of urea, superphosphate and potassium sulfate in compound fertilizer, and adapting it to different soil fertility, planting patterns and fertilizer requirements of flue-cured tobacco during its growth period, the problem of the existing fixed formula being unable to accurately supply fertilizer has been solved.

[0078] (2) By using reasonable fertilizer combinations and application schemes, the different nutrient requirements of flue-cured tobacco at different growth stages can be met, promoting root development and aroma accumulation, and avoiding growth problems caused by nutrient imbalance.

[0079] (3) The dosage and topdressing strategy can be flexibly adjusted according to the soil and planting mode, and can be adapted to the fertilizer requirements of different crops, which has strong flexibility.

[0080] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A blended fertilizer specifically for flue-cured tobacco, characterized in that, For each mu of flue-cured tobacco, calculated by weight, including: 12-16 kg of urea with a nitrogen content of 45-47%, 59-71 kg of superphosphate with a phosphorus content of 11-13%, and 29-36 kg of potassium sulfate with a potassium oxide content of 49-51%.

2. The compound fertilizer specifically for flue-cured tobacco as described in claim 1, characterized in that, The method for applying plastic film to flue-cured tobacco per acre includes the following steps: For the first top dressing, apply 2.5 to 5.5 kg of urea from the flue-cured tobacco-specific blended fertilizer within 10 days after planting. The second top dressing should be applied 19-21 days after planting, using 4.5-7.5 kg of potassium sulfate from the flue-cured tobacco-specific blended fertilizer. For base fertilizer application, mix the remaining urea, superphosphate, and potassium sulfate evenly and apply after transplanting.

3. The compound fertilizer specifically for flue-cured tobacco as described in claim 1, characterized in that, The application method for non-mulched tobacco per acre includes the following steps: For the first top dressing, apply 3.5 to 6.5 kg of urea from the flue-cured tobacco-specific blended fertilizer within 10 days after planting. The second top dressing should be applied 19-21 days after planting, using 6.5-8.5 kg of potassium sulfate from the aforementioned flue-cured tobacco-specific blended fertilizer. For base fertilizer application, mix the remaining urea, superphosphate, and potassium sulfate evenly and apply after transplanting.