A method for pretreating target target leaf spot tobacco and a curing process thereof

Abstract

The present application relates to a kind of target spot disease tobacco leaf pretreatment method and its curing process, belong to tobacco plant protection and modulation field, the target spot disease tobacco leaf pretreatment method and its curing process are selected out to be diagnosed as target spot disease tobacco leaf, after treating tobacco leaf spot, it is cured, and curing operation is carried out three times temperature cycle, through temperature control and cycle mode, the quality and taste of tobacco leaf are guaranteed.The method is suitable for multiple flue-cured tobacco varieties and has good versatility and practicality, the present application can effectively improve tobacco leaf disease leaf utilization, improve disease leaf quality, ensure tobacco taste and other aspects has obvious advantage, it has positive significance for the development of tobacco industry;Under the same curing process condition, compared with target spot disease tobacco leaf without pretreatment, the rate of high-quality tobacco of target spot disease tobacco leaf after pretreatment is higher than that of target spot disease tobacco leaf without pretreatment, the rate of high-quality tobacco is at least 7.2% higher, and tobacco evaluation score is at least 5.9 higher.

Description

Technical Field

[0001] This invention belongs to the field of tobacco plant protection and curing, and specifically relates to a method for pretreatment of tobacco leaves with target spot disease and its curing process. Background Technology

[0002] With the continuous expansion of tobacco planting area and the increasing prevalence of tobacco diseases year after year, tobacco production has become a major factor restricting tobacco yield and quality, resulting in significant economic losses for tobacco production in my country. Major tobacco leaf diseases include tobacco wildfire, tobacco red spot, tobacco angular leaf spot, tobacco virus diseases, and tobacco target spot. Tobacco target spot (Rh i zocton i aso l an i Kühn) is a newly reported disease in my country's tobacco industry in recent years. It can occur from seedling to maturity, primarily affecting the leaves, especially between topping and maturity. Initially, the lesions appear as small, brown, circular, water-soaked spots. As the lesions enlarge, concentric rings often appear, and a chlorotic halo may develop around the lesions. Some larger lesions will form perforations in the severely necrotic center, resembling the holes left by a target being shot through. Currently, the main control measures for this disease are agricultural measures and chemical control in the early stages of tobacco leaf growth, which mainly achieve the effect of prevention. However, target spot disease occurs more frequently in the middle and late stages of tobacco leaf growth in the field and is more severe on mature tobacco leaves. At this time, the effect of control is minimal.

[0003] Tobacco, as a leaf crop, is harvested from mature, yellowing leaves. Leaf quality and appearance have a decisive impact on the quality of the tobacco product. Target spot disease occurs very rapidly; once it spreads over a large area, irregular lesions with a diameter of 2-20 cm form on the leaves. The necrotic parts of these lesions are fragile and prone to perforation. Because the quality of fresh tobacco leaves infected with target spot differs significantly from that of normal fresh tobacco leaves, farmers are unsure how to cure them and are forced to abandon entire fields, resulting in substantial economic losses. Therefore, inventing a pretreatment method for tobacco leaves infected with target spot and its curing process is crucial to solving these problems.

[0004] Patent No. 202311080230.9 discloses a method for controlling tobacco target spot disease, belonging to the field of tobacco disease control technology. The method involves applying quicklime to kill the source of infection in the soil, spraying microbial agents to kill pathogens after transplanting tobacco seedlings, and spraying a control agent after cleaning the bottom leaves to effectively kill pathogens. This combined approach provides comprehensive control of tobacco target spot disease, improving control effectiveness while reducing the use of chemical pesticides and minimizing environmental pollution. However, this method cannot completely eradicate tobacco target spot disease, as infected tobacco leaves are not effectively treated. Summary of the Invention

[0005] To overcome the problems existing in the background technology, this invention discloses a pretreatment method and curing process for target spot diseased tobacco leaves. The method involves selecting tobacco leaves diagnosed with target spot disease, treating the diseased spots, and then curing them. The curing operation involves three temperature-controlled cycles. Through temperature control and the cycle method, the quality and taste of the tobacco leaves are ensured. Furthermore, this method is applicable to multiple flue-cured tobacco varieties, exhibiting good versatility and practicality. This invention has significant advantages in effectively improving the utilization rate of diseased tobacco leaves, improving the quality of diseased leaves, and ensuring the taste of tobacco leaves, thus having a positive significance for the development of the tobacco industry. Under the same curing process conditions, compared to untreated target spot diseased tobacco leaves, the yield of high-grade tobacco from pretreated target spot diseased tobacco leaves is higher, with a yield at least 7.2% higher and a tobacco evaluation score at least 5.9 higher.

[0006] To achieve the above objectives, the present invention is implemented through the following technical solution:

[0007] The method for pretreatment of tobacco leaves with target spot disease includes the following steps:

[0008] 1) Diagnosis of target spot disease in tobacco leaves;

[0009] 2) Selection of tobacco leaves with target spot disease;

[0010] 3) Classification of tobacco leaves affected by target spot disease;

[0011] 4) Treatment of target spot disease lesions on tobacco leaves.

[0012] Preferably, the target spot diseased tobacco leaves are pretreated and then dried, including the following steps: 1) sorting and packing the tobacco;

[0013] 2) First baking;

[0014] 3) Second baking.

[0015] As a preferred option, the standard for selecting target spot diseased tobacco leaves is that the diameter of a single target spot disease lesion on a single leaf is 1-5 cm, and the area of ​​the target spot disease lesion accounts for less than 5-25% of the total leaf area.

[0016] As a preferred option, the target spot disease tobacco leaf classification is based on the percentage of the target spot disease lesion area to the total area of ​​the tobacco leaf after the target spot disease tobacco leaves have been selected, and the leaves are divided into three batches.

[0017] Preferably, the three batches are as follows: the first batch has 5%-10% target spot disease lesion area, the second batch has 10%-20% target spot disease lesion area, and the third batch has 20%-25% target spot disease lesion area.

[0018] As a preferred embodiment, the steps for treating target spot diseased tobacco leaf lesions are as follows:

[0019] (1) Cut the lesions on the harvested tobacco leaves with target spot disease within a range of 2-5 mm along the edge of the lesions; (2) Spray water after cutting to complete the treatment of the lesions on the tobacco leaves with target spot disease.

[0020] As a preferred option, the sorted and packaged tobacco is made by sorting the tobacco leaves, packaging them into tobacco, and then loading them into the curing barn.

[0021] Preferably, the first curing process involves: after the tobacco leaves are loaded into the oven, ignition is performed, and the circulating fan is turned on to its maximum speed. The dry-bulb temperature is raised to 38°C at a temperature change rate of 1°C / 0.2-0.5 hours, and the wet-bulb temperature is set to 37°C. After stabilizing the temperature for 5 hours, temperature control is implemented, and the dry-bulb temperature is lowered to 37°C at a temperature change rate of 1°C / 5 hours, and the wet-bulb temperature is set to 36.5°C. After stabilizing the temperature for 1 hour, the dry-bulb temperature is lowered to 39°C at a temperature change rate of 1°C / 5 hours, and the wet-bulb temperature is set to 37.5°C. The temperature is then stabilized. One hour later, the dry-bulb temperature was lowered to 37°C again at a rate of 1°C / 5 hours, and the wet-bulb temperature was set to 36.5°C. The temperature was stabilized for 1 hour to complete one temperature cycle. This cycle was repeated three times in total. The tobacco leaves were baked until they withered, turned yellow, and softened, and the midrib softened. After the last cycle was completed and the dry-bulb temperature reached 37°C, the temperature was stabilized for 5-10 hours before the second baking began. The second baking was carried out in accordance with the "Technical Specification for Curing Tobacco (GB / T23219-2008)". After the yellowing period, the color-fixing period began.

[0022] Preferably, the curing barn is a three-layer airflow descending dense tobacco curing barn.

[0023] Preferably, the tobacco density loaded into the curing barn is 42-45 kg / m³. 3 Furthermore, the tobacco is loaded to more than 95% of the curing barn's volume.

[0024] The beneficial effects of this invention are:

[0025] (1) Effectively utilize diseased leaf resources. By diagnosing and selecting diseased tobacco leaves, usable diseased leaves are harvested in categories, making full use of diseased leaf resources that might otherwise be discarded and improving the overall utilization rate of tobacco leaves.

[0026] (2) Refined treatment of lesions: A refined treatment method was adopted. The lesions were cut with a knife and water was sprayed to increase the humidity in the drying room, promote the yellowing of diseased leaves, and thus improve the quality of diseased leaves.

[0027] (3) A variable temperature yellowing baking process was adopted. Through precise temperature control and circulation, the tobacco leaves gradually wither, turn yellow and soften during the baking process, and the main vein softens, thus ensuring the quality and taste of the tobacco leaves.

[0028] This method is applicable to multiple flue-cured tobacco varieties, including K326, Honghua Dajinyuan, and Yunyan, demonstrating good versatility and practicality. In summary, this pretreatment method for target spot diseased tobacco leaves and its curing process have significant advantages in improving the utilization rate of diseased leaves, enhancing their quality, and ensuring their taste. It has positive implications for the development of the tobacco industry. Under the same curing conditions, compared to untreated target spot diseased tobacco leaves, the yield of high-grade tobacco from pretreated target spot diseased tobacco leaves is at least 7.2% higher. Detailed Implementation

[0029] To make the above objectives, technical solutions, and beneficial effects clearer and more explicit, the present invention will be specifically described below in conjunction with embodiments.

[0030] Example 1

[0031] The experiment was conducted in Eryuan, Dali, selecting tobacco fields infected with safflower bighead carbuncle to conduct the experiment.

[0032] 1) Diagnosis of target spot disease

[0033] 2) Selection of tobacco leaves with target spot disease: Select tobacco leaves with target spot disease. The diameter of a single lesion on a single leaf is less than 5cm, and the area of ​​the lesion accounts for less than 25% of the total leaf area. These are considered usable tobacco leaves.

[0034] 3) Sorting and harvesting of tobacco leaves with target spot disease: After the leaves are selected, tobacco leaves with different proportions of diseased area to the total leaf area are sorted and harvested. A batch is formed by 5%-10% of the diseased area, a batch is formed by 10%-20% of the diseased area, and a batch is formed by 20%-25% of the diseased area.

[0035] 4) Treatment of target spot disease lesions: After the tobacco leaves are harvested, use a knife to cut the lesions within a range of 2-5mm along the edge of the lesion. After cutting, spray water. The spraying standard is: spray both sides of the upper leaves of the flue-cured tobacco. The water mist condenses into water droplets on the leaf surface and does not fall. The purpose is to increase the humidity in the curing barn by artificially replenishing water and promote the yellowing of diseased leaves.

[0036] 5) Classification and Packing of Tobacco: Tobacco leaves are cured in a three-layer dense curing barn with airflow downward. After the tobacco leaves of batches with 5%-10% diseased area are bundled, they are packed on the top layer of the curing barn. After the tobacco leaves of batches with 10%-20% diseased area are bundled, they are packed on the second top layer of the curing barn. After the tobacco leaves of batches with 20%-25% diseased area are bundled, they are packed on the bottom layer of the curing barn.

[0037] 6) First Curing: After the tobacco leaves are loaded into the oven, ignite the fire and turn the circulating fan to its maximum speed. Increase the dry-bulb temperature to 38℃ at a rate of 1℃ / 0.2h, and set the wet-bulb temperature to 37℃. Stabilize the temperature for 5h, then implement variable temperature control. Decrease the dry-bulb temperature to 37℃ at a rate of 1℃ / 5h, and set the wet-bulb temperature to 36.5℃. Stabilize the temperature for 1h, then decrease the dry-bulb temperature to 39℃ at a rate of 1℃ / 5h, and set the wet-bulb temperature to 37.5℃. Stabilize the temperature for 1h, then decrease the dry-bulb temperature to 37℃ again at a rate of 1℃ / 5h, and set the wet-bulb temperature to 36.5℃. Stabilize the temperature for 1h, completing one variable temperature cycle. Repeat this cycle 3 times in total, curing until the tobacco leaves wither, turn yellow, soften, and the midrib softens.

[0038] 7) Proceed to the second baking: After the last cycle is completed and the dry ball temperature reaches 37℃, stabilize the temperature for 5 hours, then proceed to the second baking.

[0039] Example 2

[0040] The experiment was conducted in Eryuan, Dali, selecting tobacco fields infected with safflower bighead carbuncle to conduct the experiment.

[0041] 1) Disease diagnosis

[0042] 2) Selection of usable leaves: Select tobacco leaves with target spot disease. The diameter of a single lesion on a single leaf is less than 5cm, and the area of ​​the lesion accounts for less than 25% of the total leaf area. These are usable tobacco leaves.

[0043] 3) Sorting and harvesting diseased leaves: After the leaves are sorted, tobacco leaves with diseased spots covering different proportions of the total leaf area are sorted and harvested. Leaves with diseased spots covering 5%-10% of the total leaf area are classified into one batch, leaves with diseased spots covering 10%-20% of the total leaf area are classified into another batch, and leaves with diseased spots covering 20%-25% of the total leaf area are classified into another batch.

[0044] 4) Treatment of lesions: After the tobacco leaves are harvested, use a knife to cut the lesions within a range of 2-5mm along the edge of the lesions. After cutting, spray water. The spraying standard is: spray both sides of the upper leaves of the flue-cured tobacco. The water mist condenses into water droplets on the leaf surface and does not fall. The purpose is to increase the humidity in the curing barn by artificially replenishing water and promote the yellowing of diseased leaves.

[0045] 5) Classification and Packing of Tobacco: Tobacco leaves are cured in a three-layer dense curing barn with airflow downward. After the tobacco leaves of batches with 5%-10% diseased area are bundled, they are packed on the top layer of the curing barn. After the tobacco leaves of batches with 10%-20% diseased area are bundled, they are packed on the second top layer of the curing barn. After the tobacco leaves of batches with 20%-25% diseased area are bundled, they are packed on the bottom layer of the curing barn.

[0046] 6) First Curing: After the tobacco leaves are loaded into the oven, ignite the fire and turn the circulating fan to its maximum speed. Increase the dry-bulb temperature to 38℃ at a rate of 1℃ / 0.5h, and set the wet-bulb temperature to 37℃. Stabilize the temperature for 5h, then implement variable temperature control. Decrease the dry-bulb temperature to 37℃ at a rate of 1℃ / 5h, and set the wet-bulb temperature to 36.5℃. Stabilize the temperature for 1h, then decrease the dry-bulb temperature to 39℃ at a rate of 1℃ / 5h, and set the wet-bulb temperature to 37.5℃. Stabilize the temperature for 1h, then decrease the dry-bulb temperature to 37℃ again at a rate of 1℃ / 5h, and set the wet-bulb temperature to 36.5℃. Stabilize the temperature for 1h, completing one variable temperature cycle. Repeat this cycle 3 times in total, curing until the tobacco leaves wither, turn yellow, and soften, and the midrib softens.

[0047] 7) Proceed to the second baking: After the last cycle is completed and the dry ball temperature reaches 37℃, stabilize the temperature for 10 hours, then proceed to the second baking.

[0048] Example 3

[0049] The experiment was conducted in Eryuan, Dali, selecting tobacco fields infected with safflower bighead carbuncle to conduct the experiment.

[0050] 1) Disease diagnosis

[0051] 2) Selection of usable leaves: Select tobacco leaves with target spot disease. The diameter of a single lesion on a single leaf is less than 5cm, and the area of ​​the lesion accounts for less than 25% of the total leaf area. These are usable tobacco leaves.

[0052] 3) Sorting and harvesting diseased leaves: After the leaves are sorted, tobacco leaves with diseased spots covering different proportions of the total leaf area are sorted and harvested. Leaves with diseased spots covering 5%-10% of the total leaf area are classified into one batch, leaves with diseased spots covering 10%-20% of the total leaf area are classified into another batch, and leaves with diseased spots covering 20%-25% of the total leaf area are classified into another batch.

[0053] 4) Treatment of lesions: After the tobacco leaves are harvested, use a knife to cut the lesions within a range of 2-5mm along the edge of the lesions. After cutting, spray water. The spraying standard is: spray both sides of the upper leaves of the flue-cured tobacco. The water mist condenses into water droplets on the leaf surface and does not fall. The purpose is to increase the humidity in the curing barn by artificially replenishing water and promote the yellowing of diseased leaves.

[0054] 5) Classification and Packing of Tobacco: Tobacco leaves are cured in a three-layer dense curing barn with airflow downward. After the tobacco leaves of batches with 5%-10% diseased area are bundled, they are packed on the top layer of the curing barn. After the tobacco leaves of batches with 10%-20% diseased area are bundled, they are packed on the second top layer of the curing barn. After the tobacco leaves of batches with 20%-25% diseased area are bundled, they are packed on the bottom layer of the curing barn.

[0055] 6) First Curing: After the tobacco leaves are loaded into the oven, ignite the fire and turn the circulating fan to its maximum speed. Increase the dry-bulb temperature to 38℃ at a rate of 1℃ / 0.3h, and set the wet-bulb temperature to 37℃. Stabilize the temperature for 5h, then implement variable temperature control. Decrease the dry-bulb temperature to 37℃ at a rate of 1℃ / 5h, and set the wet-bulb temperature to 36.5℃. Stabilize the temperature for 1h, then decrease the dry-bulb temperature to 39℃ at a rate of 1℃ / 5h, and set the wet-bulb temperature to 37.5℃. Stabilize the temperature for 1h, then decrease the dry-bulb temperature to 37℃ again at a rate of 1℃ / 5h, and set the wet-bulb temperature to 36.5℃. Stabilize the temperature for 1h, completing one variable temperature cycle. Repeat this cycle 3 times in total, curing until the tobacco leaves wither, turn yellow, and soften, and the midrib softens.

[0056] 7) Proceed to the second baking: After the last cycle is completed and the dry ball temperature reaches 37℃, and the temperature is stabilized for 8 hours, proceed to the second baking.

[0057] The tobacco leaves after pretreatment and curing in Examples 1, 2, and 3 are referred to as Experimental Group 1, Experimental Group 2, and Experimental Group 3, respectively.

[0058] Tobacco leaves with less than 25% lesion area from the same target spot disease site in Examples 1, 2, and 3 were harvested. However, the diseased tobacco leaves were not given any special pretreatment and were cured using the same curing process ("three-stage" curing process). The resulting flue-cured tobacco leaves were referred to as Control Group 1, Control Group 2, and Control Group 3, respectively.

[0059] The quality, sensory evaluation, and price of the first-cured tobacco leaves of experimental groups 1, 2, and 3, and examples 1, 2, and 3 were measured. The results are shown in Table 1.

[0060] Table 1. Disease incidence and initial curing quality of tobacco leaves from Dali Eryuan safflower and Dajinyuan tobacco plants.

[0061]

[0062]

[0063] As shown in Table 1, the proportion of high-quality cigarettes in experimental group 1 was 13.9% higher than that in control group 1, the average price of experimental group 1 was 7.9 yuan / kg higher than that of control group 1, and the smoking evaluation score of experimental group 1 was 11.3 higher than that of control group 1.

[0064] The proportion of premium cigarettes in experimental group 2 was 9.9% higher than that in control group 2, the average price of experimental group 2 was 6.2 yuan / kg higher than that of control group 2, and the smoking evaluation score of experimental group 2 was 9.8 higher than that of control group 2.

[0065] The proportion of high-grade cigarettes in experimental group 3 was 10.4% higher than that in control group 3. The average price of experimental group 3 was 6.0 yuan / kg higher than that of control group 3. The smoking evaluation score of experimental group 3 was 7.8 higher than that of control group 3.

[0066] Example 4

[0067] The experiment was conducted in Jiuxi Town, Yuxi, selecting tobacco fields infected with K326 target spot disease for testing.

[0068] 1) Disease diagnosis

[0069] 2) Selection of usable leaves: Select tobacco leaves with target spot disease. The diameter of a single lesion on a single leaf is less than 5cm, and the area of ​​the lesion accounts for less than 25% of the total leaf area. These are usable tobacco leaves.

[0070] 3) Sorting and harvesting diseased leaves: After the leaves are sorted, tobacco leaves with diseased spots covering different proportions of the total leaf area are sorted and harvested. Leaves with diseased spots covering 5%-10% of the total leaf area are classified into one batch, leaves with diseased spots covering 10%-20% of the total leaf area are classified into another batch, and leaves with diseased spots covering 20%-25% of the total leaf area are classified into another batch.

[0071] 4) Treatment of lesions: After the tobacco leaves are harvested, use a knife to cut the lesions within a range of 2-5mm along the edge of the lesions. After cutting, spray water. The spraying standard is: spray both sides of the upper leaves of the flue-cured tobacco. The water mist condenses into water droplets on the leaf surface and does not fall. The purpose is to increase the humidity in the curing barn by artificially replenishing water and promote the yellowing of diseased leaves.

[0072] 5) Classification and Packing of Tobacco: Tobacco leaves are cured in a three-layer dense curing barn with airflow downward. After the tobacco leaves of batches with 5%-10% diseased area are bundled, they are packed on the top layer of the curing barn. After the tobacco leaves of batches with 10%-20% diseased area are bundled, they are packed on the second top layer of the curing barn. After the tobacco leaves of batches with 20%-25% diseased area are bundled, they are packed on the bottom layer of the curing barn.

[0073] 6) First Curing: After the tobacco leaves are loaded into the oven, ignite the fire and turn the circulating fan to its maximum speed. Increase the dry-bulb temperature to 38℃ at a rate of 1℃ / 0.2h, and set the wet-bulb temperature to 37℃. Stabilize the temperature for 5h, then implement variable temperature control. Decrease the dry-bulb temperature to 37℃ at a rate of 1℃ / 5h, and set the wet-bulb temperature to 36.5℃. Stabilize the temperature for 1h, then decrease the dry-bulb temperature to 39℃ at a rate of 1℃ / 5h, and set the wet-bulb temperature to 37.5℃. Stabilize the temperature for 1h, then decrease the dry-bulb temperature to 37℃ again at a rate of 1℃ / 5h, and set the wet-bulb temperature to 36.5℃. Stabilize the temperature for 1h, completing one variable temperature cycle. Repeat this cycle 3 times in total, curing until the tobacco leaves wither, turn yellow, soften, and the midrib softens.

[0074] 7) Proceed to the second baking: After the last cycle is completed and the dry ball temperature reaches 37℃, stabilize the temperature for 5 hours, then proceed to the second baking.

[0075] Example 5

[0076] The experiment was conducted in Jiuxi Town, Yuxi, selecting tobacco fields infected with K326 target spot disease for testing.

[0077] 1) Disease diagnosis

[0078] 2) Selection of usable leaves: Select tobacco leaves with target spot disease. The diameter of a single lesion on a single leaf is less than 5cm, and the area of ​​the lesion accounts for less than 25% of the total leaf area. These are usable tobacco leaves.

[0079] 3) Sorting and harvesting diseased leaves: After the leaves are sorted, tobacco leaves with diseased spots covering different proportions of the total leaf area are sorted and harvested. Leaves with diseased spots covering 5%-10% of the total leaf area are classified into one batch, leaves with diseased spots covering 10%-20% of the total leaf area are classified into another batch, and leaves with diseased spots covering 20%-25% of the total leaf area are classified into another batch.

[0080] 4) Treatment of lesions: After the tobacco leaves are harvested, use a knife to cut the lesions within a range of 2-5mm along the edge of the lesions. After cutting, spray water. The spraying standard is: spray both sides of the upper leaves of the flue-cured tobacco. The water mist condenses into water droplets on the leaf surface and does not fall. The purpose is to increase the humidity in the curing barn by artificially replenishing water and promote the yellowing of diseased leaves.

[0081] 5) Classification and Packing of Tobacco: Tobacco leaves are cured in a three-layer dense curing barn with airflow downward. After the tobacco leaves of batches with 5%-10% diseased area are bundled, they are packed on the top layer of the curing barn. After the tobacco leaves of batches with 10%-20% diseased area are bundled, they are packed on the second top layer of the curing barn. After the tobacco leaves of batches with 20%-25% diseased area are bundled, they are packed on the bottom layer of the curing barn.

[0082] 6) First Curing: After the tobacco leaves are loaded into the oven, ignite the fire and turn the circulating fan to its maximum speed. Increase the dry-bulb temperature to 38℃ at a rate of 1℃ / 0.5h, and set the wet-bulb temperature to 37℃. Stabilize the temperature for 5h, then implement variable temperature control. Decrease the dry-bulb temperature to 37℃ at a rate of 1℃ / 5h, and set the wet-bulb temperature to 36.5℃. Stabilize the temperature for 1h, then decrease the dry-bulb temperature to 39℃ at a rate of 1℃ / 5h, and set the wet-bulb temperature to 37.5℃. Stabilize the temperature for 1h, then decrease the dry-bulb temperature to 37℃ again at a rate of 1℃ / 5h, and set the wet-bulb temperature to 36.5℃. Stabilize the temperature for 1h, completing one variable temperature cycle. Repeat this cycle 3 times in total, curing until the tobacco leaves wither, turn yellow, and soften, and the midrib softens.

[0083] 7) Proceed to the second baking: After the last cycle is completed and the dry ball temperature reaches 37℃, stabilize the temperature for 10 hours, then proceed to the second baking.

[0084] Example 6

[0085] The experiment was conducted in Jiuxi Town, Yuxi, selecting tobacco fields infected with K326 target spot disease for testing.

[0086] 1) Disease diagnosis

[0087] 2) Selection of usable leaves: Select tobacco leaves with target spot disease. The diameter of a single lesion on a single leaf is less than 5cm, and the area of ​​the lesion accounts for less than 25% of the total leaf area. These are usable tobacco leaves.

[0088] 3) Sorting and harvesting diseased leaves: After the leaves are sorted, tobacco leaves with diseased spots covering different proportions of the total leaf area are sorted and harvested. Leaves with diseased spots covering 5%-10% of the total leaf area are classified into one batch, leaves with diseased spots covering 10%-20% of the total leaf area are classified into another batch, and leaves with diseased spots covering 20%-25% of the total leaf area are classified into another batch.

[0089] 4) Treatment of lesions: After the tobacco leaves are harvested, use a knife to cut the lesions within a range of 2-5mm along the edge of the lesions. After cutting, spray water. The spraying standard is: spray both sides of the upper leaves of the flue-cured tobacco. The water mist condenses into water droplets on the leaf surface and does not fall. The purpose is to increase the humidity in the curing barn by artificially replenishing water and promote the yellowing of diseased leaves.

[0090] 5) Classification and Packing of Tobacco: Tobacco leaves are cured in a three-layer dense curing barn with airflow downward. After the tobacco leaves of batches with 5%-10% diseased area are bundled, they are packed on the top layer of the curing barn. After the tobacco leaves of batches with 10%-20% diseased area are bundled, they are packed on the second top layer of the curing barn. After the tobacco leaves of batches with 20%-25% diseased area are bundled, they are packed on the bottom layer of the curing barn.

[0091] 6) First Curing: After the tobacco leaves are loaded into the oven, ignite the fire and turn the circulating fan to its maximum speed. Increase the dry-bulb temperature to 38℃ at a rate of 1℃ / 0.3h, and set the wet-bulb temperature to 37℃. Stabilize the temperature for 5h, then implement variable temperature control. Decrease the dry-bulb temperature to 37℃ at a rate of 1℃ / 5h, and set the wet-bulb temperature to 36.5℃. Stabilize the temperature for 1h, then decrease the dry-bulb temperature to 39℃ at a rate of 1℃ / 5h, and set the wet-bulb temperature to 37.5℃. Stabilize the temperature for 1h, then decrease the dry-bulb temperature to 37℃ again at a rate of 1℃ / 5h, and set the wet-bulb temperature to 36.5℃. Stabilize the temperature for 1h, completing one variable temperature cycle. Repeat this cycle 3 times in total, curing until the tobacco leaves wither, turn yellow, and soften, and the midrib softens.

[0092] 7) Proceed to the second baking: After the last cycle is completed and the dry ball temperature reaches 37℃, and the temperature is stabilized for 8 hours, proceed to the second baking.

[0093] The tobacco leaves after pretreatment and curing in Examples 4, 5, and 6 are referred to as Experimental Group 4, Experimental Group 5, and Experimental Group 6, respectively.

[0094] Tobacco leaves with less than 25% lesion area from the same target spot disease site in Examples 4, 5, and 6 were harvested. However, the diseased tobacco leaves were not given any special pretreatment and were cured using the same curing process ("three-stage" curing process). The resulting flue-cured tobacco leaves were referred to as control group 4, control group 5, and control group 6, respectively.

[0095] The quality, sensory evaluation, and price of the first-cured tobacco leaves of experimental groups 4, 5, and 6, and examples 4, 5, and 6 were measured. The results are shown in Table 2.

[0096] Table 2. Quality of tobacco leaves infected with K326 target spot disease in Jiuxi Town, Yuxi, and at the beginning of curing.

[0097]

[0098]

[0099] As shown in Table 2, the proportion of high-quality cigarettes in experimental group 4 was 7.2% higher than that in control group 4, the average price of experimental group 4 was 4.3 yuan / kg higher than that of control group 4, and the smoking evaluation score of experimental group 4 was 5.9 higher than that of control group 4.

[0100] The proportion of high-grade cigarettes in experimental group 5 was 9.4% higher than that in control group 5. The average price of experimental group 5 was 5.0 yuan / kg higher than that of control group 5. The smoking evaluation score of experimental group 5 was 7.1 higher than that of control group 5.

[0101] The proportion of high-grade cigarettes in experimental group 6 was 8.9% higher than that in control group 6, the average price of experimental group 6 was 6.8 yuan / kg higher than that of control group 6, and the smoking evaluation score of experimental group 6 was 7.5 higher than that of control group 6.

[0102] Example 7

[0103] The experiment was conducted in Malong, Qujing, selecting tobacco fields infected with K326 target spot disease for testing.

[0104] 1) Disease diagnosis

[0105] 2) Selection of usable leaves: Select tobacco leaves with target spot disease. The diameter of a single lesion on a single leaf is less than 5cm, and the area of ​​the lesion accounts for less than 25% of the total leaf area. These are usable tobacco leaves.

[0106] 3) Sorting and harvesting diseased leaves: After the leaves are sorted, tobacco leaves with diseased spots covering different proportions of the total leaf area are sorted and harvested. Leaves with diseased spots covering 5%-10% of the total leaf area are classified into one batch, leaves with diseased spots covering 10%-20% of the total leaf area are classified into another batch, and leaves with diseased spots covering 20%-25% of the total leaf area are classified into another batch.

[0107] 4) Treatment of lesions: After the tobacco leaves are harvested, use a knife to cut the lesions within a range of 2-5mm along the edge of the lesions. After cutting, spray water. The spraying standard is: spray both sides of the upper leaves of the flue-cured tobacco. The water mist condenses into water droplets on the leaf surface and does not fall. The purpose is to increase the humidity in the curing barn by artificially replenishing water and promote the yellowing of diseased leaves.

[0108] 5) Classification and Packing of Tobacco: Tobacco leaves are cured in a three-layer dense curing barn with airflow downward. After the tobacco leaves of batches with 5%-10% diseased area are bundled, they are packed on the top layer of the curing barn. After the tobacco leaves of batches with 10%-20% diseased area are bundled, they are packed on the second top layer of the curing barn. After the tobacco leaves of batches with 20%-25% diseased area are bundled, they are packed on the bottom layer of the curing barn.

[0109] 6) First Curing: After the tobacco leaves are loaded into the oven, ignite the fire and turn the circulating fan to its maximum speed. Increase the dry-bulb temperature to 38℃ at a rate of 1℃ / 0.2h, and set the wet-bulb temperature to 37℃. Stabilize the temperature for 5h, then implement variable temperature control. Decrease the dry-bulb temperature to 37℃ at a rate of 1℃ / 5h, and set the wet-bulb temperature to 36.5℃. Stabilize the temperature for 1h, then decrease the dry-bulb temperature to 39℃ at a rate of 1℃ / 5h, and set the wet-bulb temperature to 37.5℃. Stabilize the temperature for 1h, then decrease the dry-bulb temperature to 37℃ again at a rate of 1℃ / 5h, and set the wet-bulb temperature to 36.5℃. Stabilize the temperature for 1h, completing one variable temperature cycle. Repeat this cycle 3 times in total, curing until the tobacco leaves wither, turn yellow, soften, and the midrib softens.

[0110] 7) Proceed to the second baking: After the last cycle is completed and the dry ball temperature reaches 37℃, stabilize the temperature for 5 hours, then proceed to the second baking.

[0111] Example 8

[0112] The experiment was conducted in Malong, Qujing, selecting tobacco fields infected with K326 target spot disease for testing.

[0113] 1) Disease diagnosis

[0114] 2) Selection of usable leaves: Select tobacco leaves with target spot disease. The diameter of a single lesion on a single leaf is less than 5cm, and the area of ​​the lesion accounts for less than 25% of the total leaf area. These are usable tobacco leaves.

[0115] 3) Sorting and harvesting diseased leaves: After the leaves are sorted, tobacco leaves with diseased spots covering different proportions of the total leaf area are sorted and harvested. Leaves with diseased spots covering 5%-10% of the total leaf area are classified into one batch, leaves with diseased spots covering 10%-20% of the total leaf area are classified into another batch, and leaves with diseased spots covering 20%-25% of the total leaf area are classified into another batch.

[0116] 4) Treatment of lesions: After the tobacco leaves are harvested, use a knife to cut the lesions within a range of 2-5mm along the edge of the lesions. After cutting, spray water. The spraying standard is: spray both sides of the upper leaves of the flue-cured tobacco. The water mist condenses into water droplets on the leaf surface and does not fall. The purpose is to increase the humidity in the curing barn by artificially replenishing water and promote the yellowing of diseased leaves.

[0117] 5) Classification and Packing of Tobacco: Tobacco leaves are cured in a three-layer dense curing barn with airflow downward. After the tobacco leaves of batches with 5%-10% diseased area are bundled, they are packed on the top layer of the curing barn. After the tobacco leaves of batches with 10%-20% diseased area are bundled, they are packed on the second top layer of the curing barn. After the tobacco leaves of batches with 20%-25% diseased area are bundled, they are packed on the bottom layer of the curing barn.

[0118] 6) First Curing: After the tobacco leaves are loaded into the oven, ignite the fire and turn the circulating fan to its maximum speed. Increase the dry-bulb temperature to 38℃ at a rate of 1℃ / 0.5h, and set the wet-bulb temperature to 37℃. Stabilize the temperature for 5h, then implement variable temperature control. Decrease the dry-bulb temperature to 37℃ at a rate of 1℃ / 5h, and set the wet-bulb temperature to 36.5℃. Stabilize the temperature for 1h, then decrease the dry-bulb temperature to 39℃ at a rate of 1℃ / 5h, and set the wet-bulb temperature to 37.5℃. Stabilize the temperature for 1h, then decrease the dry-bulb temperature to 37℃ again at a rate of 1℃ / 5h, and set the wet-bulb temperature to 36.5℃. Stabilize the temperature for 1h, completing one variable temperature cycle. Repeat this cycle 3 times in total, curing until the tobacco leaves wither, turn yellow, and soften, and the midrib softens.

[0119] 7) Proceed to the second baking: After the last cycle is completed and the dry ball temperature reaches 37℃, stabilize the temperature for 10 hours, then proceed to the second baking.

[0120] Example 9

[0121] The experiment was conducted in Malong, Qujing, selecting tobacco fields infected with K326 target spot disease for testing.

[0122] 1) Disease diagnosis

[0123] 2) Selection of usable leaves: Select tobacco leaves with target spot disease. The diameter of a single lesion on a single leaf is less than 5cm, and the area of ​​the lesion accounts for less than 25% of the total leaf area. These are usable tobacco leaves.

[0124] 3) Sorting and harvesting diseased leaves: After the leaves are sorted, tobacco leaves with diseased spots covering different proportions of the total leaf area are sorted and harvested. Leaves with diseased spots covering 5%-10% of the total leaf area are classified into one batch, leaves with diseased spots covering 10%-20% of the total leaf area are classified into another batch, and leaves with diseased spots covering 20%-25% of the total leaf area are classified into another batch.

[0125] 4) Treatment of lesions: After the tobacco leaves are harvested, use a knife to cut the lesions within a range of 2-5mm along the edge of the lesions. After cutting, spray water. The spraying standard is: spray both sides of the upper leaves of the flue-cured tobacco. The water mist condenses into water droplets on the leaf surface and does not fall. The purpose is to increase the humidity in the curing barn by artificially replenishing water and promote the yellowing of diseased leaves.

[0126] 5) Classification and Packing of Tobacco: Tobacco leaves are cured in a three-layer dense curing barn with airflow downward. After the tobacco leaves of batches with 5%-10% diseased area are bundled, they are packed on the top layer of the curing barn. After the tobacco leaves of batches with 10%-20% diseased area are bundled, they are packed on the second top layer of the curing barn. After the tobacco leaves of batches with 20%-25% diseased area are bundled, they are packed on the bottom layer of the curing barn.

[0127] 6) First Curing: After the tobacco leaves are loaded into the oven, ignite the fire and turn the circulating fan to its maximum speed. Increase the dry-bulb temperature to 38℃ at a rate of 1℃ / 0.3h, and set the wet-bulb temperature to 37℃. Stabilize the temperature for 5h, then implement variable temperature control. Decrease the dry-bulb temperature to 37℃ at a rate of 1℃ / 5h, and set the wet-bulb temperature to 36.5℃. Stabilize the temperature for 1h, then decrease the dry-bulb temperature to 39℃ at a rate of 1℃ / 5h, and set the wet-bulb temperature to 37.5℃. Stabilize the temperature for 1h, then decrease the dry-bulb temperature to 37℃ again at a rate of 1℃ / 5h, and set the wet-bulb temperature to 36.5℃. Stabilize the temperature for 1h, completing one variable temperature cycle. Repeat this cycle 3 times in total, curing until the tobacco leaves wither, turn yellow, and soften, and the midrib softens.

[0128] 7) Proceed to the second baking: After the last cycle is completed and the dry ball temperature reaches 37℃, and the temperature is stabilized for 8 hours, proceed to the second baking.

[0129] The tobacco leaves after pretreatment and curing in Examples 7, 8, and 9 are referred to as Experimental Group 7, Experimental Group 8, and Experimental Group 9, respectively.

[0130] In Examples 7, 8, and 9, tobacco leaves with less than 25% lesion area from the same target spot disease site were harvested. However, the diseased tobacco leaves were not given any special pretreatment and were cured using the same curing process ("three-stage" curing process). The resulting flue-cured tobacco leaves were referred to as control group 7, control group 8, and control group 9, respectively.

[0131] The quality, sensory evaluation, and price of the first-cured tobacco leaves of experimental groups 7, 8, and 9, and examples 7, 8, and 9 were measured. The results are shown in Table 3.

[0132] Table 3. Quality of tobacco leaves affected by target spot disease (K326) in Qujing Malong, and the quality of newly cured tobacco leaves.

[0133]

[0134] As shown in Table 3, the quality of the superior cigarettes in the experimental group 7 was 7.2% higher than that in the control group 7, the average price of the experimental group 7 was 4.3 yuan / kg higher than that of the control group 7, and the smoking score of the experimental group 7 was 5.9 higher than that of the control group 7.

[0135] The quality of the superior cigarettes in the experimental group 8 was 9.4% higher than that in the control group 8. The average price of the experimental group 8 was 5.0 yuan / kg higher than that of the control group 8. The smoking evaluation score of the experimental group 8 was 7.1 higher than that of the control group 8.

[0136] The quality of the superior cigarettes in the experimental group 9 was 8.9% higher than that in the control group 9. The average price of the experimental group 9 was 6.8 yuan / kg higher than that of the control group 9. The smoking evaluation score of the experimental group 9 was 7.5 higher than that of the control group 9.

[0137] Finally, it should be noted that the above preferred embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail through the above preferred embodiments, those skilled in the art should understand that various changes can be made to it in form and detail without departing from the scope defined by the claims of the present invention.

Claims

1. A method for pretreatment of tobacco leaves with target spot disease, characterized in that: Includes the following steps: 1) Diagnosis of target spot disease in tobacco leaves; 2) Selection of tobacco leaves affected by target spot disease; 3) Classification of tobacco leaves affected by target spot disease; 4) Treatment of target spot disease lesions on tobacco leaves; The tobacco leaves with target spot disease are pretreated and then dried, including the following steps: 1) Categorizing and packaging cigarettes; 2) First baking; 3) Second baking; The selection criteria for target spot diseased tobacco leaves are: tobacco leaves with a single target spot disease lesion diameter of 1-5 cm and a target spot disease lesion area accounting for less than 5-25% of the total leaf area are considered target spot diseased tobacco leaves; The target spot disease classification of tobacco leaves is based on the percentage of target spot disease area to the total area of ​​the tobacco leaf after the target spot disease is selected, and the leaves are divided into three batches. The three batches are as follows: the first batch has 5%-10% target spot disease lesions on the tobacco leaves; the second batch has 10%-20% target spot disease lesions on the tobacco leaves; and the third batch has 20%-25% target spot disease lesions on the tobacco leaves. The steps for treating the target spot diseased tobacco leaves are as follows: (1) After harvesting, cut the target spot diseased tobacco leaves along the edge of the lesion within a range of 2-5 mm; (2) After cutting, spray water to complete the treatment of the target spot diseased tobacco leaves. The classified and packaged tobacco is made by arranging classified tobacco leaves into tobacco and then loading them into a curing barn. The curing barn is a three-layer airflow descending dense tobacco curing barn. The loading density of the tobacco into the curing barn is 42-45 kg / m3 and the tobacco is loaded to more than 95% of the curing barn volume. The first curing process involves the following steps: After the tobacco leaves are loaded into the oven, the fire is ignited, and the circulating fan is turned to its maximum speed. The dry-bulb temperature is raised to 38°C at a rate of 1°C per 0.2-0.5 hours, and the wet-bulb temperature is set to 37°C. After stabilizing this temperature for 5 hours, a temperature-changing control is implemented. The dry-bulb temperature is lowered to 37°C at a rate of 1°C per 5 hours, and the wet-bulb temperature is set to 36.5°C. After stabilizing this temperature for 1 hour, the dry-bulb temperature is lowered to 39°C at a rate of 1°C per 5 hours, and the wet-bulb temperature is set to 37.5°C. After stabilizing this temperature for 1 hour, the dry-bulb temperature is lowered to 37°C again at a rate of 1°C per 5 hours, and the wet-bulb temperature is set to 36.5°C. This process is repeated for 1 hour, completing one temperature-changing cycle. This cycle is repeated three times in total. The tobacco leaves are cured until they wilt, turn yellow, and soften, and the midrib softens. After the final cycle reaches a dry-bulb temperature of 37°C and is stabilized for 5-10 hours, the second curing process begins. The second curing is conducted according to the "Technical Specification for Curing Tobacco (GB / T)". According to the standard (23219-2008), the color-fixing period begins after the yellowing period ends.

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