A method to increase the nicotine content of tobacco leaves under rainy and low-sunlight climate conditions

Abstract

This invention discloses a method for increasing the nicotine content of tobacco leaves under rainy and low-sunlight conditions, belonging to the field of agricultural planting technology. The method includes: transplanting; applying nitrogen fertilizer: nitrogen fertilizer is applied in three stages, using a mixture of ammonium nitrogen fertilizer and nitrate nitrogen fertilizer. The ammonium nitrogen fertilizer is ammonium sulfate or ammonium bicarbonate, and the nitrate nitrogen fertilizer is calcium ammonium nitrate or potassium nitrate; spraying foliar fertilizer: amino acid foliar fertilizer, potassium dihydrogen phosphate foliar fertilizer, and water are mixed at a volume-to-mass ratio of 50mL:45g:15kg to obtain a foliar fertilizer mixture. The first foliar spray is applied 60 days after transplanting, followed by spraying once a week for three consecutive times. The application rate of the foliar fertilizer mixture is 45-50kg / mu; topping: topping is performed 15-20 days after initial flowering, leaving 18 leaves per plant; curing. This invention can promote photosynthesis, accelerate nicotine synthesis, and slow down the nicotine conversion process, thereby reducing nicotine loss.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of agricultural planting technology, more particularly to a method for improving the nicotine content of tobacco leaves under a climate condition of heavy rain and little sunshine. BACKGROUND

[0002] Nicotine, as the main alkaloid in tobacco leaves, has a crucial impact on the quality of tobacco leaves. It not only affects the appearance color of tobacco leaves, making them present a unique brown-red color, but also forms aroma substances through high-temperature decomposition, improving the aroma quality of tobacco leaves. At the same time, nicotine is closely related to the taste of tobacco leaves, and the ratio of its free state and bound state determines the irritability and physiological intensity of tobacco leaves, which in turn affects the satisfaction of smokers.

[0003] The nicotine content of tobacco leaves is generally between 1.5% and 3.5%, and the optimal content for high-quality tobacco leaves is 2.5%. This content range can ensure that the tobacco leaves have moderate physiological intensity and aroma, while avoiding the problems of excessive irritability caused by high nicotine content or dull taste caused by low nicotine content.

[0004] Heavy rain and little sunshine have a significant impact on nicotine content. First, heavy rain can lead to excessive soil moisture, which in turn increases soil humidity. This humid environment can interfere with the normal respiration of tobacco root systems, reducing root activity and indirectly affecting the synthesis and accumulation of nicotine. In addition, humid soil is prone to nitrogen loss, leading to reduced nitrogen uptake by tobacco plants. Since nitrogen is an essential element for nicotine synthesis, its insufficient supply will directly lead to a decrease in nicotine content in tobacco leaves. On the other hand, light, as an important environmental factor for nicotine synthesis, its deficiency will also have a negative impact on nicotine content. Under conditions of little sunshine, the photosynthesis of tobacco plants will be weakened, leading to reduced physiological activity of tobacco plants, which in turn affects the synthesis and accumulation of nicotine. At the same time, insufficient light will also lead to slow growth of tobacco plants, with thin and small leaves and loose tissue, which will further affect the accumulation of nicotine.

[0005] In the southern tobacco-growing areas of China, during the summer, when tobacco plants are in the vigorous growth period, heavy rainfall often occurs for a long duration. Along with the phenomenon of heavy rain, there is also a phenomenon of little sunshine. In the southern tobacco-growing areas, due to thick clouds and frequent rainfall, the number of sunshine hours is significantly reduced. In addition to the low number of sunshine hours, the southern tobacco-growing areas also exhibit weak light intensity under the condition of little sunshine, which affects the synthesis of nicotine in tobacco leaves.

[0006] Therefore, the climate phenomenon of much rain and little sunshine in the southern tobacco growing area has a significant influence on the growth of tobacco and the synthesis of nicotine. In order to cope with the problem of further reducing the quality of tobacco caused by the low nicotine content of tobacco caused by the adverse climate conditions, it is an urgent problem for those skilled in the art to develop a method for increasing the nicotine content of tobacco under the climate conditions of much rain and little sunshine. SUMMARY

[0007] Therefore, the climate phenomenon of much rain and little sunshine in the southern tobacco growing area has a significant influence on the growth of tobacco and the synthesis of nicotine. In order to cope with the problem of further reducing the quality of tobacco caused by the low nicotine content of tobacco caused by the adverse climate conditions, it is an urgent problem for those skilled in the art to develop a method for increasing the nicotine content of tobacco under the climate conditions of much rain and little sunshine.

[0008] In order to achieve the above-mentioned purpose, the present application adopts the following technical solutions:

[0009] A method for increasing the nicotine content of tobacco under the climate conditions of much rain and little sunshine, comprising the following steps:

[0010] (1) Transplanting: planting tobacco seedlings according to a cultivation density of 900-950 plants per mu;

[0011] (2) Applying nitrogen fertilizer: applying nitrogen fertilizer three times: the first time is one day before transplanting, the second time is 7-10 days after transplanting, and the third time is 40-45 days after transplanting, and ammonium nitrogen and nitrate nitrogen are used in a mixed manner, wherein the ammonium nitrogen accounts for 60wt%, and the nitrate nitrogen accounts for 40wt%, the ammonium nitrogen is ammonium sulfate or ammonium bicarbonate, and the nitrate nitrogen is calcium nitrate or potassium nitrate;

[0012] The total nitrogen fertilizer is applied in an amount of pure N: 9kg / mu, 30% of the total amount is applied the first time, 30% of the total amount is applied the second time, and 40% of the total amount is applied the third time;

[0013] (3) Spraying foliar fertilizer: mixing amino acid foliar fertilizer, potassium dihydrogen phosphate foliar fertilizer and water in a volume-mass ratio of 50mL:45g:15kg to obtain foliar fertilizer mixed solution, and spraying the foliar fertilizer mixed solution for the first time on the 60th day after transplanting tobacco, spraying once every other week, and continuously spraying for 3 times, and the spraying amount of the foliar fertilizer mixed solution is 45-50kg / mu each time;

[0014] (4) Topping: topping is performed 15-20 days after initial flowering, and the number of leaves is controlled to be 18 per plant;

[0015] (5) Curing: curing the tobacco leaves after harvesting, the yellowing stage: the dry ball temperature is 36℃, the color fixing stage: the color fixing time is 80h, and the dry stem stage.

[0016] Further, the specific steps of the yellowing stage are as follows: after the tobacco leaves are loaded into the curing barn, the door of the curing barn is closed to start curing, the dry ball temperature is increased to 36℃ at a speed of 1℃ / h, the wet ball temperature is 34℃, and the temperature is stabilized for 60h.

[0017] Further, the specific steps of the color fixing stage are: increasing the dry ball temperature to 48℃ at a speed of 0.5℃ / h, the wet ball temperature is 45℃, and the temperature is kept stable for 80h.

[0018] Further, the specific steps of the dry muscle stage are: increasing the dry ball temperature to 64℃ at a speed of 2℃ / h, the wet ball temperature is 42℃, and the temperature is kept stable for 48h.

[0019] The beneficial effects of the present application are:

[0020] 1. The present application appropriately reduces the transplanting density, which can increase the light intensity received by the tobacco plants in the field, increase the individual nutrient area of the tobacco plants, promote photosynthesis, and accelerate nicotine synthesis.

[0021] 2. The present application appropriately supplements ammonium nitrogen, which is more conducive to accelerating the biosynthesis and accumulation of nicotine in tobacco leaves than nitrate nitrogen.

[0022] 3. The application amount of nitrogen fertilizer has a significant effect on the nicotine content of tobacco leaves, and appropriately increasing the nitrogen fertilizer can promote nicotine synthesis.

[0023] 4. Amino acids are important precursor substances for plant chlorophyll synthesis, and after spraying, they can be directly absorbed and utilized by plant leaves, increasing chlorophyll content. Phosphorus elements participate in the process of photosynthesis of plants, and potassium elements help the transportation and metabolism of substances in plants. After the combination of the two is sprayed, the photosynthetic efficiency of the leaves can be effectively improved.

[0024] 5. Topping is an important measure in tobacco cultivation, which will affect the synthesis and accumulation of nicotine. Late topping can promote root growth, thereby increasing nicotine synthesis, so the present application requires delaying the topping time.

[0025] 6. In order to increase the nicotine content of the leaves, the present application controls the number of leaves to 18 per plant, because when the number of leaves is reduced, limited nutrients will be more concentratedly allocated to the remaining leaves, including related substances that promote nicotine synthesis.

[0026] 7. During the yellowing period of tobacco leaves, high temperature can accelerate the degradation and transformation process of nicotine, while low temperature can slow down this process. Therefore, the present application adopts the method of low-temperature slow curing, which is beneficial to reducing the transformation of nicotine.

[0027] 8. The color fixing stage is a critical period for the transformation of nicotine during tobacco curing, and by prolonging the time of this stage, the present application can slow down the transformation process of nicotine, thereby reducing the loss of nicotine. DETAILED DESCRIPTION

[0028] The technical solutions in the embodiments of the present application will be clearly and completely described below with the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments of the present application, all the other embodiments obtained by a person of ordinary skill in the art without creative effort belong to the protection scope of the present application.

[0029] Example 1

[0030] The method for improving the nicotine content of tobacco leaves under the climate condition of rainy and little sunshine comprises the following steps:

[0031] (1) transplanting: in Yangguang Town, Tonghai County, Yuxi City, Yunnan Province, tobacco seedlings are planted according to a planting density of 900 plants per mu;

[0032] (2) applying nitrogen fertilizer: nitrogen fertilizer is applied in three times: the first time is one day before transplanting, the second time is 7 days after transplanting, and the third time is 40 days after transplanting. Ammonium nitrogen fertilizer and nitrate nitrogen fertilizer are used in a mixed manner, wherein the ammonium nitrogen fertilizer accounts for 60 wt%, and the nitrate nitrogen fertilizer accounts for 40 wt%. The ammonium nitrogen fertilizer is ammonium sulfate, and the nitrate nitrogen fertilizer is calcium ammonium nitrate;

[0033] The total nitrogen fertilizer is applied in an amount of pure N: 9 kg per mu. The first time is 30% of the total amount, the second time is 30% of the total amount, and the third time is 40% of the total amount;

[0034] (3) spraying foliar fertilizer: foliar fertilizer mixed solution is obtained by mixing amino acid foliar fertilizer (amino acid content: ≥15%, total content of zinc, boron, manganese, copper and iron trace elements: not less than 25%), potassium dihydrogen phosphate foliar fertilizer (P2O5: 52%; K2O: 34%) and water in a volume-to-mass ratio of 50 mL: 45 g: 15 kg. The first time of foliar spraying is performed 60 days after transplanting tobacco, and spraying is performed every other week, for a total of 3 times. The spraying amount of the foliar fertilizer mixed solution is 45 kg per mu each time;

[0035] (4) topping: topping is performed 15 days after initial flowering, and the number of leaves is controlled to be 18 per plant;

[0036] (5) curing: after the tobacco leaves are harvested, the tobacco leaves are cured. In the yellowing stage, the tobacco leaves are loaded into a curing room, the door of the curing room is closed to start curing, the dry ball temperature is increased to 36℃ at a speed of 1℃ / h, the wet ball temperature is 34℃, and the temperature is stabilized for 60 h. In the color fixing stage, the dry ball temperature is increased to 48℃ at a speed of 0.5℃ / h, the wet ball temperature is 45℃, and the temperature is stabilized for 80 h. In the dry stem stage, the dry ball temperature is increased to 64℃ at a speed of 2℃ / h, the wet ball temperature is 42℃, and the temperature is stabilized for 48 h.

[0037] Comparative Example 1

[0038] (1) Transplanting: In Yangguang Town, Tonghai County, Yuxi City, Yunnan Province, the control and the adjacent fields were separated by field ridges and the field ridges were wrapped with plastic film to prevent mutual leakage. The tobacco seedlings were planted at a cultivation density of 1100 plants / mu.

[0039] (2) Apply nitrogen fertilizer: Apply ammonium calcium nitrate fertilizer in three applications: the first application one day before transplanting, the second application 7 days after transplanting, and the third application 40 days after transplanting; the total amount of nitrogen fertilizer applied each time is 7 kg / mu of pure N, 30% of the total amount applied in the first application, 30% of the total amount applied in the second application, and 40% of the total amount applied in the third application.

[0040] (3) Topping: Topping should be carried out on the 3rd day after the initial flowering, and the number of leaves should be controlled to 22 per plant;

[0041] (4) Curing: After the tobacco leaves are harvested, they are cured. Yellowing stage: After the tobacco leaves are put into the curing barn, the door of the curing barn is closed and curing begins. The dry bulb temperature is increased to 36℃ at a rate of 1℃ / h, the wet bulb temperature is 34℃, and the temperature is stabilized for 60h. Color fixing stage: The dry bulb temperature is increased to 48℃ at a rate of 0.5℃ / h, the wet bulb temperature is 45℃, and the temperature is stabilized for 80h. Drying stage: The dry bulb temperature is increased to 64℃ at a rate of 2℃ / h, the wet bulb temperature is 42℃, and the temperature is stabilized for 48h.

[0042] Table 1. Tobacco growth and production in Example 1 and Control 1

[0043]

[0044] As shown in Table 1, compared with Comparative Example 1, the yield of Example 1 increased by 1.78%, and the output value increased by 2.65%. The nicotine content in the middle leaves of Example 1 increased by 21.24% compared with Comparative Example 1, and the nicotine content in the upper leaves of Example 1 increased by 17.49% compared with Control 1.

[0045] These data indicate that the flue-cured tobacco of Example 1 exhibits certain advantages in terms of growth and production, particularly in terms of significantly improved nicotine content.

[0046] Example 2

[0047] Methods to increase the nicotine content of tobacco leaves under rainy and low-sunlight conditions include the following steps:

[0048] (1) Transplanting: In Hexi Town, Tonghai County, Yuxi City, Yunnan Province, tobacco seedlings were planted at a planting density of 900 plants / mu;

[0049] (2) Apply nitrogen fertilizer: Apply nitrogen fertilizer in three times: the first time one day before transplanting, the second time 8 days after transplanting, and the third time 42 days after transplanting. Mix ammonium nitrogen fertilizer and nitrate nitrogen fertilizer, with ammonium nitrogen fertilizer accounting for 60wt% and nitrate nitrogen fertilizer accounting for 40wt%. The ammonium nitrogen fertilizer is ammonium sulfate and the nitrate nitrogen fertilizer is calcium ammonium nitrate.

[0050] The total nitrogen fertilizer application rate is 9 kg / mu (pure N), with the first application accounting for 30% of the total amount, the second application accounting for 30% of the total amount, and the third application accounting for 40% of the total amount.

[0051] (3) Foliar fertilizer application: Mix amino acid foliar fertilizer (amino acid content: ≥15%, total content of trace elements such as zinc, boron, manganese, copper and iron not less than 25%), potassium dihydrogen phosphate foliar fertilizer (P2O5: 52%; K2O: 34%) and water in a volume-mass ratio of 50mL:45g:15kg to obtain foliar fertilizer mixture. Apply the first foliar spray on the 60th day after the flue-cured tobacco is transplanted, and spray once every week for a total of 3 times. The amount of foliar fertilizer mixture to be sprayed is 45kg / mu each time.

[0052] (4) Topping: Topping should be carried out 15 days after the initial flowering, and the number of leaves should be controlled to 18 per plant;

[0053] (5) Curing: After the tobacco leaves are harvested, they are cured. Yellowing stage: After the tobacco leaves are put into the curing barn, the door of the curing barn is closed and curing begins. The dry bulb temperature is increased to 36℃ at a rate of 1℃ / h, the wet bulb temperature is 34℃, and the temperature is maintained for 60h. Color fixation stage: The dry bulb temperature is increased to 48℃ at a rate of 0.5℃ / h, the wet bulb temperature is 45℃, and the temperature is maintained for 80h. Drying stage: The dry bulb temperature is increased to 64℃ at a rate of 2℃ / h, the wet bulb temperature is 42℃, and the temperature is maintained for 48h.

[0054] Comparative Example 2

[0055] Methods to increase the nicotine content of tobacco leaves under rainy and low-sunlight conditions include the following steps:

[0056] (1) Transplanting: In Hexi Town, Tonghai County, Yuxi City, Yunnan Province, the same field as Example 2 was used. The control and the adjacent fields were separated by field ridges and the field ridges were wrapped with plastic film to prevent mutual leakage. The tobacco seedlings were planted at a cultivation density of 1100 plants / mu.

[0057] (2) Apply nitrogen fertilizer: Apply nitrogen fertilizer in three times: the first time one day before transplanting, the second time 8 days after transplanting, and the third time 42 days after transplanting. Mix ammonium nitrogen fertilizer and nitrate nitrogen fertilizer, with ammonium nitrogen fertilizer accounting for 60wt% and nitrate nitrogen fertilizer accounting for 40wt%. The ammonium nitrogen fertilizer is ammonium sulfate and the nitrate nitrogen fertilizer is calcium ammonium nitrate.

[0058] The total amount of nitrogen fertilizer applied each time is 7 kg of pure N per mu. The first application is 30% of the total amount, the second application is 30% of the total amount, and the third application is 40% of the total amount.

[0059] (3) Topping: Topping should be carried out on the 3rd day after the initial flowering, and the number of leaves should be controlled to 22 per plant;

[0060] (4) Curing: After the tobacco leaves are harvested, they are cured. Yellowing stage: After the tobacco leaves are put into the curing barn, the door of the curing barn is closed and curing begins. The dry bulb temperature is increased to 36℃ at a rate of 1℃ / h, the wet bulb temperature is 34℃, and the temperature is stabilized for 60h. Color fixing stage: The dry bulb temperature is increased to 48℃ at a rate of 0.5℃ / h, the wet bulb temperature is 45℃, and the temperature is stabilized for 80h. Drying stage: The dry bulb temperature is increased to 64℃ at a rate of 2℃ / h, the wet bulb temperature is 42℃, and the temperature is stabilized for 48h.

[0061] Table 2. Flue-cured tobacco production and nicotine levels in Example 2 and Comparative Example 2.

[0062]

[0063]

[0064] Comparative analysis of the data in Table 2 shows that, compared to Comparative Example 2, the yield of Example 2 increased by 0.47%, and the output value increased by 2.26%. Although the increases are not large, they both show a positive growth trend. The nicotine content in the middle leaves of Example 2 increased by 30.69% compared to Comparative Example 2, and the nicotine content in the upper leaves of Example 2 increased by 17.83% compared to Comparative Example 2. These two increases are relatively large, indicating that Example 2 is significantly effective in increasing nicotine content.

[0065] The above shows that, compared with Comparative Example 2, Example 2 has improved in terms of flue-cured tobacco yield, output value and nicotine content, especially the nicotine content has increased significantly.

[0066] In summary, the treatment measures in this embodiment have a significant promoting effect on the growth and economic benefits of flue-cured tobacco, especially in terms of significantly increasing the nicotine content. This is an effective method that is worth further promotion and application in flue-cured tobacco production.

[0067] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for increasing the nicotine content of tobacco leaves under conditions of high rainfall and low sunlight, characterized in that, Comprising the following steps: (1) Transplanting: planting tobacco seedlings according to a cultivation density of 900-950 plants / mu; (2) Applying nitrogen fertilizer: applying nitrogen fertilizer three times: the first time is one day before transplanting, the second time is 7-10 days after transplanting, and the third time is 40-45 days after transplanting, and ammonium nitrogen and nitrate nitrogen are mixed for use, wherein ammonium nitrogen accounts for 60wt%, and nitrate nitrogen accounts for 40wt%, the ammonium nitrogen is ammonium sulfate or ammonium bicarbonate, and the nitrate nitrogen is calcium nitrate or potassium nitrate; The total nitrogen fertilizer application amount is pure N: 9kg / mu, 30% of the total amount is applied the first time, 30% of the total amount is applied the second time, and 40% of the total amount is applied the third time; (3) Spraying foliage fertilizer: mixing amino acid foliage fertilizer, potassium dihydrogen phosphate foliage fertilizer and water according to a volume mass ratio of 50mL:45g:15kg to obtain foliage fertilizer mixed solution, and spraying foliage for the first time on the 60th day after transplanting tobacco, spraying once every other week, continuously spraying for 3 times, and the spraying amount of the foliage fertilizer mixed solution is 45-50kg / mu each time; (4) Topping: topping 15-20 days after initial flowering, and controlling the number of leaves to 18 leaves per plant; (5) Curing: curing tobacco leaves after harvesting, yellowing stage: dry ball temperature is 36℃, color fixing stage: color fixing time is 80h; dry tendon stage.

2. The method for increasing the nicotine content of tobacco leaves under rainy and low-sunlight climatic conditions according to claim 1, characterized in that, The specific steps of the yellowing stage are: after loading tobacco leaves into a curing room, closing the door of the curing room to start curing, increasing the dry ball temperature to 36℃ at a speed of 1℃ / h, the wet ball temperature is 34℃, and the temperature is stabilized for 60h.

3. The method for increasing the nicotine content of tobacco leaves under rainy and low-sunlight climatic conditions according to claim 1, characterized in that, The specific steps of the color fixing stage are: increasing the dry ball temperature to 48℃ at a speed of 0.5℃ / h, the wet ball temperature is 45℃, and the temperature is stabilized for 80h.

4. The method for increasing the nicotine content of tobacco leaves under rainy and low-sunlight climatic conditions according to claim 1, characterized in that, The specific steps of the dry tendon stage are: increasing the dry ball temperature to 64℃ at a speed of 2℃ / h, the wet ball temperature is 42℃, and the temperature is stabilized for 48h.

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