Cultivation and production technology of flue-cured tobacco variety Yuzhou 201

Abstract

The invention discloses a cultivation and production technology of a flue-cured tobacco variety Yuzhou 201. The cultivation and production technology comprises the following steps: (1) selecting a tobacco field; (2) performing winter ploughing and ridging; (3) sowing time; (4) scientific transplanting; (5) balanced fertilization; (6) field management; (7) tobacco field plant protection; (8) harvesting; and (9) tobacco leaf baking. The tobacco leaves planted and harvested through the method are high in quality, sensory evaluation results show that the smoking quality of the tobacco leaves meets industrial requirements, and the overall sensory quality of the tobacco leaves planted through the method shows that the tobacco leaves are rich and comfortable in fragrance, good in fragrance quality, obvious in sweetness, high in fragrance amount, high in smoke concentration and moderate in strength; the high-quality strong-flavor tobacco leaf raw material is high in quality, low in irritation, comfortable in aftertaste, small in offensive odor and high in overall smoking quality, and meets the requirements of high-grade cigarettes.

Description

Technical Field

[0001] The invention relates to the technical field of flue-cured tobacco planting, and in particular to a cultivation and production technology of a flue-cured tobacco variety, Yu Nong Xiang 201. Background Art

[0002] The Yu Nong Xiang 201 variety uses the high-quality Zhongyan 100 as the improvement object, and through EMS mutagenesis and multi-faceted selection, a new flue-cured tobacco variety Yu Nong Xiang 201 was bred. This variety was approved by the National Tobacco Variety Approval Committee in April 2023.

[0003] The parent, Zhongyan 100, is a variety bred by the Tobacco Research Institute of the Chinese Academy of Agricultural Sciences. It passed the identification in 2002 and is resistant to tobacco brown spot disease and black shank disease, moderately resistant to root-knot nematode disease and mild climate spot disease, and has strong adaptability. It has strong field growth, a well-developed root system, large leaves and high yield. Its disadvantages are a long growing period and small internode distance.

[0004] Characteristics of Yu Nong Xiang 201: The plant is tower-shaped, and becomes cylindrical after topping. The plant height after topping is 160-170cm. The leaves are long oval, with gradually pointed tips, wavy leaf margins, and slightly wrinkled leaves. The stem circumference is 10.5cm, and the internode distance is 5.0-6.0cm. The number of leaves that can be harvested is 20-22. The waist leaf is 60-70cm long and 30-35cm wide. The leaves are long oval, with gradually pointed tips, wavy leaf margins, and slightly wrinkled leaves. The leaves are spread and wide, and the main veins are of medium thickness. The inflorescence is scattered, and the corolla is pink. It takes 60-65 days from transplanting to the central flower opening, and the field growth period is about 120 days. This variety is resistant to black leg disease No. 1 and Fusarium root rot, moderately resistant to root knot nematodes, and moderately susceptible to TMV and CMV. In order to obtain high-quality flue-cured tobacco Yu Nong Xiang 201 variety, the present invention further improves and optimizes the existing planting management to improve the yield and quality of the obtained flue-cured tobacco Yu Nong Xiang 201 variety. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a cultivation and production technology for a flue-cured tobacco variety Yu Nong Xiang 201, so as to solve the problem of insufficient tobacco leaf quality and yield in the existing flue-cured tobacco planting technology, so as to improve the overall sensory quality and yield of tobacco leaves.

[0006] The technical problem to be solved by the present invention is achieved through the following technical solutions:

[0007] A cultivation and production technology for a flue-cured tobacco variety Yu Nong Xiang 201 comprises the following steps:

[0008] (1) Tobacco field selection: Choose land with medium or higher fertility;

[0009] (2) Winter ploughing and ridging: Ridging should be done from the end of December of the previous year to January of the following year, preferably after snowfall and clear weather.

[0010] (3) Sowing period: Sowing should be concentrated from February 25 to March 5 of the following year, and greenhouse preparation should be done before sowing;

[0011] (4) Scientific transplanting: including the selection of transplanting time, planting density, and transplanting methods in accordance with local conditions;

[0012] (5) Balanced fertilization: insist on combining organic and inorganic fertilizers, combining basal fertilizer with topdressing, combining nitrogen, phosphorus, potassium with trace elements, and fertilizing at a time consistent with the fertilizer requirements of tobacco plants;

[0013] (6) Field management: including tillage and weeding, film removal and soil cultivation, water-saving irrigation, structure optimization, and topping and leaf retention;

[0014] (7) Tobacco field plant protection: prevent and control viral diseases and root and stem diseases;

[0015] (8) Harvesting: Harvesting tobacco leaves from different parts according to their maturity;

[0016] (9) Tobacco leaf baking: follow the “three-stage” baking plan.

[0017] Preferably, in step (3), the greenhouse preparation work includes reinforcement of greenhouse facilities, substrate fumigation, and tray disinfection; wherein the temperature in the greenhouse is controlled at 20-26°C.

[0018] Preferably, in step (4),

[0019] The transplanting time is divided into regular transplanting time and seedling transplanting time under film. The regular transplanting time is from April 20 to May 1 of the following year; the seedling transplanting time under film is from April 10 to April 15 of the following year.

[0020] The planting density is 1.3 meters in row and 0.60-0.70 meters in plant spacing;

[0021] The transplanting method comprises the following steps: selecting robust tobacco seedlings for transplanting, checking the seedlings in time for replanting 7-10 days after the transplanting, and watering the weak seedlings and small seedlings with biased water and applying biased fertilizer.

[0022] Preferably, in step (5), the amount of fertilizer applied is determined as follows: for medium-fertility tobacco fields: that is, plots with a quick-acting nitrogen content of 45-70 mg / kg, or plateaus with a wheat yield of 400-500 kg / mu or hilly and mountainous areas with a wheat yield of 200-300 kg / mu; for plateaus, 3-3.5 kg of pure nitrogen is applied per mu, and for hilly and mountainous areas, 4-4.5 kg of pure nitrogen is applied per mu;

[0023] Specific fertilization methods include:

[0024] (51) Base fertilizer: Before ridge formation, apply 40 kg of charcoal cake fertilizer, 5 kg of potassium sulfate and 25 kg of tobacco fertilizer per mu in narrow strips along the center line of the ridge body; 20 kg of zinc sulfate, 1 kg of borax, 5 kg of magnesium hydroxide and 50 g of ammonium molybdate as base fertilizer at one time;

[0025] (52) Hole fertilizer: When transplanting, mix 5 kg of tobacco fertilizer, 2 kg of potassium nitrate and 10 kg of charcoal cake fertilizer per mu with the soil and apply it in the holes to prevent excessive concentration of fertilizers, which may cause root burn and seedling injury.

[0026] (53) Top dressing: 3 kg of potassium nitrate should be applied by drip irrigation at the clumping stage or dissolved in water for irrigation. 15 kg of potassium sulfate should be applied by drip irrigation three times, 45 days, 60 days and 75 days after transplanting. In areas where conditions permit, it is recommended to use high-efficiency liquid potassium fertilizer. Generally, 5 kg of high-efficiency liquid potassium fertilizer per mu per drip irrigation is appropriate.

[0027] Preferably, in step (53), the topdressing is specifically:

[0028] (531) Topdressing: When tobacco plants enter the vigorous growth period, apply the remaining 20% ​​of potassium sulfate fertilizer. Make a hole 10-15 cm deep 10-15 cm away from the stem circumference, pour the fertilizer solution into the hole in a fixed amount or inject it with a back injection device, and then seal the hole with soil.

[0029] When the tobacco plants reach maturity, apply the remaining 30% of potassium sulfate fertilizer;

[0030] (532) Foliar fertilization: When tobacco plants show signs of nutrient deficiency or severe imbalance, foliar fertilization should be applied. Foliar fertilization is mainly carried out during the clustering stage, vigorous growth stage and dome stage. Spraying should be carried out after 4 p.m. on a sunny or cloudy day without wind. Spraying should be done on both sides. The concentration of the fertilizer applied is calculated by weight percentage as follows: 0.5-1.0% potassium dihydrogen phosphate, 0.5-1.0% potassium sulfate, 0.5-1.0% potassium nitrate, and the rest is water.

[0031] Preferably, step (6) is specifically:

[0032] a. Intertillage and weeding: Intertillage should be frequent and deep, combined with soiling, and the ridge should be enlarged to promote the main root to grow deep and the lateral root to expand. The first time is after the seedlings are returned, specifically 10 days after planting, with shallow intertillage and small soiling; the second time is before the tobacco plants enter the clustering stage, specifically 20-25 days after planting, with large intertillage and high soiling combined with fertilization; the third intertillage is carried out 5-7 days before topping, to remove weeds, eliminate compaction, and remove 1-2 old leaves near the ground to ensure that the tobacco leaves near the ground are well ventilated and light-permeable;

[0033] b. Remove the film and add soil: Remove the film and add soil 35-45 days after transplanting. When adding soil, the loose soil on the surface of the soil should be closely combined with the base of the stem. After adding soil, the furrows should be straight, flat, and free of weeds. The surface of the soil should be tile-shaped and 30 cm high. All the remaining film removed should be removed from the tobacco field and centrally processed. Add soil in time after removing the film;

[0034] c. Water-saving irrigation: Water-saving irrigation is carried out according to the water demand of tobacco plants at different growth stages and in combination with climatic conditions. No watering is done during the seedling stage and the early stage of clustering. In severe cases where tobacco leaves wilt and drought cannot be recovered in the afternoon, point irrigation or a small amount of irrigation is used for alternate rows. Pay attention to drought during the vigorous growth period and irrigate enough "vigorous growth water". Fertilizer is adjusted with water to keep the soil moisture at 80-85% of the maximum water holding capacity. During the maturity period, dome water and mature yellowing water are irrigated according to the soil moisture conditions to keep the soil moisture at 50-60% of the maximum water holding capacity.

[0035] d. Optimize structure:

[0036] (1) Secondary optimization: Before and after the tobacco plants bud, clean the 4-5 bottom leaves below, and top the plants when 50% of the central flowers are open. After topping, remove the lower leaves that are under-illuminated, poorly developed, and of poor quality. When harvesting and baking the upper leaves, discard the 2-3 top leaves that are poorly developed, poorly opened, and of poor quality. During the tobacco leaf harvesting process, the diseased and damaged leaves should be promptly cleaned out of the tobacco field and buried in a pit;

[0037] (2) Removal of unsuitable tobacco leaves before roasting: Fresh tobacco is classified when it is braided, and fresh tobacco leaves of poor quality are further removed, including unripe leaves, overripe leaves, and diseased leaves;

[0038] e. Topping and leaving leaves: The topping period and the number of leaves to be left should be determined according to the growth of tobacco plants and soil fertility. Normally, 50% of the tobacco plants in the tobacco field are toppled when the central flowers are in bloom, leaving 20-22 leaves. In drought, "topping is done twice". The first topping only removes the inflorescence. After rainfall, topping is done again according to the growth of the tobacco plants and the number of leaves to be left should be determined. Tobacco fields with high fertility and vigorous growth should be toppled during the peak flowering period and more leaves should be left. Tobacco fields with low fertility and weak growth should be done the opposite. The height of topping and the number of leaves to be left should be based on the standard of whether the tobacco plants can form a "round top". It is necessary to prevent topping too low and leaving too few leaves, and the upper leaves being too large and thick, with coarse veins and exposed stems, forming "umbrella-shaped" tobacco plants. It is necessary to ensure that the upper leaves can open the stalks and pieces. After topping, artificial branch removal or chemical bud inhibitors are used to inhibit buds. In the mature period, it is ensured that there are no flowers in the tobacco fields and no messy branches on the tobacco plants. The removed flower branches and tobacco branches are promptly cleared out of the tobacco fields for centralized treatment.

[0039] Preferably, in step (7),

[0040] Viral disease prevention and control includes:

[0041] s1. Virus-free seedling production: During seedling raising, follow the operating procedures, fully disinfect the seedling trays and greenhouses, set up insect-proof nets, hang insect-attracting boards in the greenhouses, disinfect the operating equipment during thinning and leaf cutting, and prohibit smoking in the seedling greenhouses to reduce the spread of viral diseases on tobacco seedlings;

[0042] s2. Agricultural control: Antiviral agents should be sprayed before field operations. According to the principle of treating healthy plants first and then diseased plants, prevent artificial infection when digging seedlings, weeding, and removing film to build up soil. Diseased tobacco fields should be cleared, soiled, and top-dressed in a timely manner. Diseased and damaged leaves should be removed from the tobacco fields in a timely manner, and sprayed with pesticides;

[0043] s3. Chemical control: 1-3 days before transplanting, spray 3000 times diluted 3% supersensitive protein microparticles on the seedbed, and spray once with 4000-5000 times diluted 7-10 days after transplanting. Spray for the third time during the clustering stage or the early stage of virus disease.

[0044] When the disease occurs in the field, use 20% morpholino hydrochloride wettable powder 2000 times, or 20% morpholino copper acetate wettable powder 800--1200 times, or 8% ningnanmycin aqueous solution 1200--1600 times, and use trace elements at the same time, spray once every 7--10 days;

[0045] Root and tuber disease control includes the following:

[0046] s4. Prevention and control at the seedling stage: Strengthen the disinfection of seedling trays and seedling greenhouses, and use the substrate mixing technology to add biological agents to the substrate in a certain proportion, stir evenly and then raise seedlings;

[0047] s5. Agricultural control: Rotate crops with gramineous crops for more than three years; plough and sun-dry in winter; build high ridges and plant tobacco deep, with the ridge height above 25cm; timely tillage and weeding, remove film and cultivate soil, and drain water after rain; timely remove diseased plants and disinfect the soil around diseased plants;

[0048] s6. Biological control: Use biological agents to prevent root and stem diseases, apply charcoal-based organic fertilizer 200kg / mu; when transplanting, pour soluble biological agents into the holes with water; from the cluster stage to before vigorous growth, mix the biological agents into fully fermented soybean milk for root irrigation;

[0049] s7. Chemical control: Observe the occurrence of the disease. At the early stage of the disease, find the diseased center plant and spray the stem base of the center plant and 10-20 tobacco plants around it with pesticides once every 7-10 days for two times in a row.

[0050] For black shank disease, use 68% carbendazim·mancozeb water dispersible granules, or 600-800 times diluted 72% carbendazim·mancozeb wettable powder, or 600-800 times diluted 50% flumorph·ethylene aluminum wettable powder. For root rot, use 800-1000 times diluted 70% methyl thiophanate wettable powder by spraying the base of the stem or irrigating the roots.

[0051] Preferably, the biological agent comprises: Trichoderma harzianum, Bacillus subtilis, and Bacillus polymyxa; the biological agent is injected into the holes along with water at a mass percentage of 5% of the biological agent used, and the injection amount is 15-20 mL per plant; the mass ratio of the biological agent to the fully fermented soy milk is 1:10-15; the root injection amount is 8-10 mL per plant; wherein, fungicides cannot be applied within one week before and after the application of the biological agent.

[0052] Preferably, the harvesting in step (8) is specifically:

[0053] Maturity: Yu Nong Xiang 201 has medium leaf thickness;

[0054] The lower leaves are harvested early when they are ripe and yellowish in color;

[0055] The middle leaves are harvested when they are mature. The leaves turn yellow, 2 / 3--4 / 5 of the main veins turn white and shiny, the leaves droop, the groove under the leaf tip rolls inward, and the angle between the stem and the leaves increases.

[0056] For the upper leaves, when the surface turns white and shiny, some leaves show mature spots, the leaf tips curl inward, and appear slightly scorched, and the main and branch veins turn white and shiny, and when they are fully mature, the upper 4-6 leaves can be harvested at one time.

[0057] Preferably, in the "three-stage" baking of step (9), since the lower tobacco leaves turn yellow quickly and are not resistant to baking, the yellowing time can be appropriately shortened to set the color early; the middle leaves are resistant to baking and easy to bake, the yellowing dehydration temperature should not be too low, and the color should not be fixed too quickly; the yellowing temperature of the upper tobacco leaves should be appropriately increased, the moisture should not be removed too quickly, and the temperature stabilization time of the key temperature point during the color fixing period should be appropriately extended. In view of the lighter color of the tobacco leaves after baking, the humidity during the yellowing and color fixing period can be appropriately increased, specifically including:

[0058] (1) Early stage of yellowing: After the oven is ignited, the temperature rises at a rate of 1h / ℃ until the dry bulb temperature reaches 38℃ and the wet bulb temperature reaches 37℃, and the temperature is kept stable for 50-60 hours;

[0059] (2) Middle stage of yellowing: Raise the dry-bulb temperature to 40°C at a rate of 2h / °C, maintain the wet-bulb temperature at 37°C, and keep the temperature steady for about 15 hours;

[0060] (3) Late yellowing stage: Raise the dry-bulb temperature to 42°C at a rate of 2h / °C, maintain the wet-bulb temperature at 37°C, and keep the temperature steady for 12-18 hours;

[0061] (4) Early stage of color fixation: increase the dry bulb temperature to 45°C and the wet bulb temperature to 38°C at a rate of 2h / °C and keep the temperature stable for 12 hours;

[0062] (5) Late color fixation: Raise the temperature to 54°C at 2h / °C, adjust the wet-bulb temperature to 38.5°C-39.5°C, and keep the temperature stable for 36 hours;

[0063] (6) Early stage of drying: raise the temperature to 60°C at 1h / °C, adjust the wet-bulb temperature to 41°C, and keep the temperature stable for 12 hours;

[0064] (7) Late drying stage: Raise the temperature to 68°C at 1h / °C, adjust the wet-bulb temperature to 42°C, and maintain the temperature for 26 hours until the main vein and stem are completely dry.

[0065] The above technical solution of the present invention has the following beneficial effects:

[0066] (1) The tobacco leaves planted and harvested by the method of the present invention are of high quality. The sensory evaluation results reflect the smoking quality of the tobacco leaves. The overall sensory quality of the tobacco leaves planted by the method of the present invention is characterized by rich and full aroma, sufficient aroma, good aroma quality, high smoke concentration, moderate strength, low irritation, comfortable aftertaste, light impurities, and high overall smoking quality, which is suitable for most people.

[0067] (2) The planting management method of the present invention can keep the flue-cured tobacco variety Yu Nong Xiang 201 uniform in the field, and its main botanical traits are genetically stable, with a well-developed root system, thick stems, and robust field growth. When the field is dry in the early stage, the leaves crawl on the ground, grow roots first, then leaves, and the leaves grow fully horizontally. The characteristics of the cluster stage are obvious, and the internodes elongate rapidly after entering the vigorous growth stage.

[0068] (3) After the flue-cured tobacco planted by the present invention is harvested, the original tobacco is uniform in color, mostly golden, has good maturity, has a loose leaf structure, has a little oil content, is of moderate thickness, has good overall appearance quality, has a relatively coordinated chemical composition, has a good aroma quality, has a sufficient aroma volume, has a moderate smoke concentration and strength, has a comfortable aftertaste, has a good sweet aftertaste, has a good overall sensory quality, and can be welcomed by most people.

[0069] (4) The planting and management method of the present invention can harvest high-quality upper tobacco leaves with a higher yield, and the harvested tobacco leaves have the characteristics of thick and full smoke concentration and rich aroma, which can significantly improve the taste concentration and enrich the tobacco aroma.

[0070] (5) The present invention uses a series of specific management methods to carry out planting, and the harvested tobacco leaves are fully nutritious, have a high total sugar content, are well developed, and have high maturity resistance, and can obtain more high-quality six-leaf tobacco leaves. The method of the present invention can significantly promote the increase of tobacco yield, the improvement of tobacco quality, and the improvement of economic benefits by rationally regulating the amount of nitrogen fertilizer, planting density, and field management. Under the planting management method of the present invention, the light interception and light distribution of the flue-cured tobacco population can be improved, thereby improving the photosynthesis of the flue-cured tobacco population, improving the absorption of nutrients in the tobacco leaves, and the accumulation and conversion of aroma substances, thereby improving the quality of the tobacco leaves. BRIEF DESCRIPTION OF THE DRAWINGS

[0071] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.

[0072] Figure 1 A step diagram of a method for planting and managing the flue-cured tobacco variety Yu Nong Xiang 201 of the present invention;

[0073] Figure 2 The production data of the high-quality tobacco leaves of the embodiment of the present invention and the comparative example are compared (KG / mu). DETAILED DESCRIPTION

[0074] Various exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It should be noted that the relative arrangement of components and steps, numerical expressions and numerical values ​​set forth in these embodiments do not limit the scope of the present invention unless otherwise specifically stated.

[0075] A cultivation and production technology for a flue-cured tobacco variety Yu Nong Xiang 201 comprises the following steps:

[0076] (1) Tobacco field selection: Choose land with medium or higher fertility;

[0077] (2) Ridge making in winter: Ridge making should be done from the end of December of the previous year to January of the following year, preferably after snowfall and clear weather. The standard is that the ridges should be full and straight like a line.

[0078] (3) Sowing period: Sowing should be concentrated from February 25 to March 5 of the following year. Before sowing, the greenhouse should be prepared for sowing. The greenhouse preparation work includes the reinforcement of greenhouse facilities, substrate fumigation, and tray disinfection. The temperature in the greenhouse should be controlled at 20-26°C. When the temperature in the greenhouse is lower than 18°C, it should be sealed to keep warm and moist. When the temperature in the greenhouse exceeds 30°C, ventilation should be turned on to cool down.

[0079] (4) Scientific transplanting:

[0080] These include: transplanting time selection, planting density, and cultivation time;

[0081] Transplanting time: divided into:

[0082] Conventional transplanting time: April 20th to May 1st of the following year;

[0083] Transplanting time of seedlings under film: April 10th to April 15th of the following year;

[0084] Among them, the planting density is: row spacing is 1.3 meters, plant spacing is 0.6--0.7 meters, and 900--1000 tobacco plants are planted per mu;

[0085] Among them, cultivation technology: choose healthy tobacco seedlings for transplanting, check the seedlings and replant them in time 7-10 days after transplanting, and water the weak and small seedlings with biased water and apply biased fertilizer.

[0086] (5) Balanced fertilization:

[0087] Fertilization principles: adhere to the combination of organic and inorganic fertilizers, base fertilizer and topdressing, nitrogen, phosphorus, potassium and trace elements, and the fertilization time should be consistent with the fertilizer requirements of tobacco plants; Determination of fertilizer amount: for medium-fertility tobacco fields: that is, plots with a quick-acting nitrogen content of 45-70 mg / kg, or plateaus with a wheat yield of 400-500 kg / mu or hilly and mountainous areas with a wheat yield of 200-3000 kg / mu; for plateaus, apply 3-3.5 kg of pure nitrogen per mu, and for hilly and mountainous areas, apply 4-4.5 kg of pure nitrogen per mu;

[0088] Step (5) base fertilizer: before ridging, 40 kg of carbon bacteria cake formula fertilizer, 5 kg of potassium sulfate and 25 kg of tobacco-specific fertilizer are applied in narrow strips along the center line of the ridge body; 20 kg of zinc sulfate, 1 kg of borax, 5 kg of magnesium hydroxide and 50 g of ammonium molybdate are applied as base fertilizer at one time;

[0089] Hole fertilizer: When transplanting, mix 5 kg of tobacco fertilizer, 2 kg of potassium nitrate and 10 kg of carbon cake fertilizer per mu with the soil and apply it in the holes to prevent excessive concentration of fertilizers, which may cause root burn and seedling injury.

[0090] Top dressing: 3 kg of potassium nitrate should be applied by drip irrigation during the clumping stage or dissolved in water for irrigation; 15 kg of potassium sulfate should be applied by drip irrigation three times, at 45 days, 60 days and 75 days after transplanting.

[0091] The specific application is:

[0092] ① Topdressing of soil: When tobacco plants enter the vigorous growth period, apply the remaining 20% ​​of potassium sulfate fertilizer. Make a hole 10-15cm deep 10-15cm away from the stem circumference, pour the fertilizer solution quantitatively or inject it with a back injection device, and then seal the hole with soil;

[0093] When the tobacco plants reach maturity, apply the remaining 30% of potassium sulfate fertilizer;

[0094] ② Foliar fertilization: When tobacco plants show a lack of or severe imbalance of nutrients, foliar spraying of fertilizers is used. Foliar spraying of fertilizers is mainly carried out during the clumping stage, vigorous growth stage and dome stage. Spraying should be carried out after 4 pm on a sunny or cloudy day without wind. Spraying should be done on both sides. The spraying concentration of fertilizers is calculated by weight percentage as follows: potassium dihydrogen phosphate 0.50-1.0%, potassium sulfate 0.5-1.0%, potassium nitrate 0.5-1.0%, and the rest is water.

[0095] (6) Field management:

[0096] a. Intertillage and weeding: Intertillage should be frequent and deep, combined with soiling, and the ridge should be enlarged to promote the main root to grow and the lateral root to expand. The first time is after the seedlings are returned, specifically 10 days after planting, with shallow intertillage and small soiling; the second time is before the tobacco plants enter the clustering stage, specifically 20-25 days after planting, with large intertillage and high soiling combined with fertilization, and 1-2 leaves near the ground should be removed at the same time; the third intertillage should be carried out 5-7 days before topping, to remove weeds, eliminate compaction, and remove 1-2 old leaves near the ground to ensure good ventilation and light transmission of tobacco leaves near the ground;

[0097] b. Remove the film and add soil: Remove the film and add soil 35-45 days after transplanting. When adding soil, the loose soil on the surface of the soil should be closely combined with the base of the stem. After adding soil, the furrows should be straight, flat, and free of weeds. The surface of the soil should be tile-shaped and 30 cm high. All the remaining film removed should be removed from the tobacco field and centrally processed. Add soil in time after removing the film to avoid root damage caused by untimely adding soil.

[0098] c. Water-saving irrigation: Water-saving irrigation is carried out according to the water demand of tobacco plants at different growth stages and in combination with climatic conditions. No watering is done during the seedling stage and the early stage of clustering. In severe cases where tobacco leaves wilt and drought cannot be recovered in the afternoon, point irrigation or a small amount of alternate-row irrigation is used. Pay attention to drought during the vigorous growth period and irrigate enough "vigorous growth water". Fertilizer is adjusted with water to keep soil moisture at 80-85% of the maximum water holding capacity. During the maturity period, dome water and mature yellowing water are irrigated according to the soil moisture conditions to keep soil moisture at 50-60% of the maximum water holding capacity.

[0099] dOptimized structure:

[0100] (1) Secondary optimization: Before and after the tobacco plants bud, clean the 4-5 bottom leaves below, and top the plants when 50% of the central flowers are open. After topping, remove the lower leaves that are under-illuminated, poorly developed, and of poor quality. When harvesting and baking the upper leaves, discard the 2-3 top leaves that are poorly developed, poorly opened, and of poor quality. During the tobacco leaf harvesting process, the diseased and damaged leaves should be promptly cleaned out of the tobacco field and buried in a pit;

[0101] (2) Removal of unsuitable tobacco leaves before roasting: Fresh tobacco is classified when it is braided, and fresh tobacco leaves of poor quality are further removed, including unripe leaves, overripe leaves, and diseased leaves;

[0102] e. Topping and leaving leaves: Determine the topping period and the number of leaves to be left according to the growth of tobacco plants and soil fertility. Normally, 30% of the tobacco plants in the tobacco field are toppled when the central flowers are in bloom, leaving 20-22 leaves. In drought, "topping is done twice". The first topping only removes the inflorescence. After rainfall, topping is done again according to the growth of the tobacco plants and the number of leaves to be left is determined. Tobacco fields with high fertility and vigorous growth should be toppled during the peak flowering period and more leaves should be left, while tobacco fields with low fertility and weak growth should be done the opposite. The height of topping and the number of leaves to be left should be based on the standard of whether the tobacco plants can form a "round top". It is necessary to prevent topping too low and leaving too few leaves, and preventing the upper leaves from being too large and thick, with coarse veins and exposed stems, forming an "umbrella-shaped" tobacco plant. It is necessary to ensure that the upper leaves can open the stalks and pieces. After topping, artificial branch removal or chemical bud inhibitors are used to inhibit buds. In the mature period, ensure that there are no flowers in the tobacco fields and no messy branches on the tobacco plants. The removed flower branches and tobacco branches are cleared out of the tobacco fields for centralized treatment.

[0103] (7) Tobacco field plant protection: Effectively prevent and control viral diseases and root and tuber diseases.

[0104] Viral disease prevention and control includes:

[0105] s1. Virus-free seedling production: During seedling raising, follow the operating procedures, fully disinfect the seedling trays and greenhouses, set up insect-proof nets, hang insect-attracting boards in the greenhouses, disinfect the operating equipment during thinning and leaf cutting, and prohibit smoking in the seedling greenhouses to reduce the spread of viral diseases on tobacco seedlings;

[0106] s2. Agricultural control: Antiviral agents should be sprayed before field operations. According to the principle of treating healthy plants first and then diseased plants, prevent artificial infection when digging seedlings, weeding, and removing film to build up soil. Diseased tobacco fields should be cleared, soiled, and top-dressed in a timely manner. Diseased and damaged leaves should be removed from the tobacco fields in a timely manner, and sprayed with pesticides;

[0107] s3. Chemical control: 1-3 days before transplanting, spray 3000 times diluted 3% supersensitive protein microparticles on the seedbed, and spray once with 4000-5000 times diluted 7-10 days after transplanting. Spray for the third time during the clustering stage or the early stage of virus disease.

[0108] When the disease occurs in the field, use 20% morpholino hydrochloride wettable powder 2000 times, or 20% morpholino copper acetate wettable powder 800--1200 times, or 8% ningnanmycin aqueous solution 1200--1600 times, and use trace elements at the same time, spray once every 7--10 days;

[0109] Root and tuber disease control includes the following:

[0110] s4. Prevention and control at the seedling stage: Strengthen the disinfection of seedling trays and seedling greenhouses, and use the substrate mixing technology to add biological agents to the substrate in a certain proportion, stir evenly and then raise seedlings;

[0111] s5. Agricultural control: Rotate crops with gramineous crops for more than three years; plough and sun-dry in winter; build high ridges and plant tobacco deep, with the ridge height above 25cm; timely tillage and weeding, remove film and cultivate soil, and drain water after rain; timely remove diseased plants and disinfect the soil around diseased plants;

[0112] s6. Biological control: Use biological agents to prevent the occurrence of root and stem diseases, and apply charcoal-based fertilizer and organic fertilizer at 200kg / mu; when transplanting, pour soluble biological agents into the holes along with water; from the clumping stage to the beginning of vigorous growth, mix the biological agents into the fully fermented soy milk and irrigate the roots.

[0113] s7. Chemical control: Observe the occurrence of the disease. At the early stage of the disease, find the diseased center plant and spray the stem base of the center plant and 10-20 tobacco plants around it with pesticides once every 7-10 days for two times in a row.

[0114] For black shank disease, use 68% carbendazim·mancozeb water dispersible granules, or 600-800 times diluted 72% carbendazim·mancozeb wettable powder, or 600-800 times diluted 50% flumorph·ethylene aluminum wettable powder. For root rot, use 800-1000 times diluted 70% methyl thiophanate wettable powder by spraying the base of the stem or irrigating the roots.

[0115] Biological agents include Trichoderma harzianum, Bacillus subtilis, and Paenibacillus polymyxa;

[0116] The biological agent is injected into the hole with water, and the mass percentage of the biological agent used is 5%, and the injection volume is 15-20mL per plant;

[0117] The mass ratio of the biological agent to the fully fermented soy milk is 1:10-15;

[0118] The root irrigation amount is 8-10mL per plant;

[0119] Among them, fungicides cannot be applied within one week before and after the application of biological agents.

[0120] (8) Harvesting:

[0121] Maturity: Yu Nong Xiang 201 has medium leaf thickness;

[0122] The lower leaves are harvested early when they are ripe and yellowish in color;

[0123] The middle leaves are harvested when they are mature. The leaves turn yellow, 2 / 3 of the main veins turn white and shiny, the leaves droop, and the angle between the stems and leaves increases.

[0124] For the upper leaves, when mature spots appear on the leaf surface and the main and branch veins turn white, and when they are fully mature, the upper 4-6 leaves can be harvested at one time.

[0125] (9) Key points of baking technology:

[0126] Yu Nong Xiang 201 has good yellowing in field stratification and is easy to bake. It can be baked according to the conventional "three-stage" baking process. The lower tobacco leaves turn yellow quickly and are not resistant to baking. The yellowing time can be appropriately shortened to fix the color early; the middle leaves are resistant to baking and easy to bake, the yellowing dehydration temperature should not be too low, and the color should not be fixed too quickly; the yellowing temperature of the upper tobacco leaves should be appropriately increased, the moisture should not be removed too quickly, and the temperature stabilization time at the key temperature point during the color fixing period should be appropriately extended. In view of the lighter color of the tobacco leaves after baking, the humidity during the yellowing and color fixing period can be appropriately increased.

[0127] The following are specific embodiments:

[0128] Example 1

[0129] A method for planting and managing a flue-cured tobacco variety Yu Nong Xiang 201 comprises the following steps:

[0130] (1) Tobacco field selection: Choose land with medium or higher fertility;

[0131] (2) Ridge making in winter: Ridge making should be done from the end of December of the previous year to January of the following year, preferably after snowfall and clear weather. The standard is that the ridges should be full and straight like a line.

[0132] (3) Sowing period: Sowing should be concentrated on February 25 of the following year. Before sowing, the greenhouse should be prepared for sowing. The greenhouse preparation work includes the reinforcement of greenhouse facilities, substrate fumigation, and tray disinfection. The temperature in the greenhouse should be controlled at 25°C.

[0133] (4) Scientific transplanting:

[0134] Including: transplanting time selection, planting density, cultivation time; Transplanting time: divided into:

[0135] Conventional transplanting time: April 26 of the following year;

[0136] Transplanting time of seedlings under film: April 15 of the following year;

[0137] Among them, the planting density is: row spacing is 1.3 meters, plant spacing is 0.6 meters, and 1,000 tobacco plants are planted per mu;

[0138] Among them, cultivation technology: choose healthy tobacco seedlings for transplanting, check the seedlings and replant them 7 days after transplanting, and water the weak and small seedlings with biased water and apply biased fertilizer.

[0139] (5) Balanced fertilization:

[0140] Fertilization principles: adhere to the combination of organic and inorganic fertilizers, base fertilizer and topdressing, nitrogen, phosphorus, potassium and trace elements, and the fertilization time is consistent with the fertilizer requirements of tobacco plants; determination of fertilizer amount: for medium fertility tobacco fields: wheat yield is 200-300kg / mu of plateau; for plateaus, apply 3.5kg of pure nitrogen per mu;

[0141] The fertilizer application rate per mu is:

[0142] 15:15:15 25kg of compound fertilizer, 200kg of carbon-based fertilizer, 5kg of potassium nitrate, 20kg of potassium sulfate, and 20kg of sesame cake fertilizer.

[0143] As a further technical solution, the specific fertilization method in step (5) is as follows: the specific fertilization method in step (5) is as follows: 100% compound fertilizer, 100% sesame cake fertilizer, 50% potassium sulfate and all carbon-based fertilizers are used as base fertilizers, and applied in furrows at the time of ridge formation, with a furrow depth of 15 cm, and then ridge formation is performed;

[0144] Potassium nitrate should be applied in holes during transplanting and along with watering; the remaining 50% potassium sulfate should be applied twice with melted water during the vigorous growth period and the mature period.

[0145] Strip application: double furrows are dug at the bottom of the ridges to mix all carbon-based fertilizers, compound fertilizers, sesame cake fertilizers, and 50% potassium sulfate fertilizers evenly and apply them in strips with a furrow depth of 15 cm, and then ridges are formed;

[0146] Hole application: Apply all potassium nitrate into the hole as seedling fertilizer; mix the hole application fertilizer with the soil thoroughly;

[0147] Top dressing: When tobacco plants show signs of nutrient deficiency or severe imbalance, apply fertilizers containing corresponding nutrients; apply 50% potassium sulfate fertilizer twice in melted water during the vigorous growth period and mature period.

[0148] The specific application is:

[0149] ① Topdressing of soil: When tobacco plants enter the vigorous growth period, apply the remaining 20% ​​of potassium sulfate fertilizer. Make a 10cm deep hole 10cm away from the stem circumference, pour the fertilizer solution quantitatively or inject it with a back injection device, and then seal the hole with soil;

[0150] When the tobacco plants reach maturity, apply the remaining 30% of potassium sulfate fertilizer;

[0151] ② Foliar fertilization: When tobacco plants show a lack of or severe imbalance of nutrients, foliar spraying of fertilizers is used. Foliar spraying of fertilizers is mainly carried out during the clumping stage, vigorous growth stage and dome stage. Spraying should be carried out after 4 pm on a sunny or cloudy day without wind. Spraying should be done on both sides. The spraying concentration of fertilizers is calculated by weight percentage as follows: 0.50% potassium dihydrogen phosphate, 0.5% potassium sulfate, 0.5% potassium nitrate, and the rest is water.

[0152] (6) Field management:

[0153] a. Intertillage and weeding: Intertillage should be frequent and deep, combined with soiling, and the ridge should be enlarged to promote the main root to grow deep and the lateral root to expand. The first time is after the seedlings are returned, specifically 10 days after planting, with shallow intertillage and small soiling; the second time is before the tobacco plants enter the cluster stage, specifically 20 days after planting, with large intertillage and high soiling combined with fertilization; the third intertillage is carried out 5 days before topping, to remove weeds, eliminate compaction, and remove one old leaf near the ground to ensure good ventilation and light transmission of tobacco leaves near the ground;

[0154] b. Remove the film and add soil: 35 days after transplanting, remove the film and add soil. When adding soil, the loose soil on the surface of the soil should be closely combined with the base of the stem. After adding soil, the furrows should be straight, flat, and free of weeds. The surface of the soil should be tile-shaped and 30 cm high. All the remaining film removed should be removed from the tobacco field and centrally processed. Add soil in time after removing the film to avoid root damage caused by untimely adding soil.

[0155] c. Water-saving irrigation: Water-saving irrigation is carried out according to the water demand of tobacco plants at different growth stages and in combination with climatic conditions. No watering is done during the seedling stage and the early stage of clustering. In severe cases where tobacco leaves wilt and drought cannot be recovered in the afternoon, point irrigation or a small amount of irrigation is used for alternate rows. Pay attention to drought during the vigorous growth period and irrigate enough "vigorous growth water". Fertilizer is adjusted with water to keep the soil moisture at 80% of the maximum water holding capacity. During the maturity period, dome water and mature yellowing water are irrigated according to the soil moisture conditions to keep the soil moisture at 50% of the maximum water holding capacity.

[0156] dOptimized structure:

[0157] (1) Secondary optimization: Before and after the tobacco plants bud, clean the 5-6 bottom leaves below. After topping, remove the lower leaves that are insufficiently illuminated, poorly developed, and of poor quality. When the tobacco leaves in the lower two sheds are mature and ready for harvesting, remove at least 2 more leaves. When harvesting the upper leaves, discard the 2 top leaves that are poorly developed, poorly opened, and of poor quality. During the tobacco leaf harvesting process, remove the diseased and damaged leaves from the tobacco field in a timely manner and bury them in a pit.

[0158] (2) Removal of unsuitable tobacco leaves before roasting: Fresh tobacco is classified when it is braided, and fresh tobacco leaves of poor quality are further removed, including unripe leaves, overripe leaves, and diseased leaves;

[0159] e. Topping and leaving leaves: Determine the topping period and the number of leaves to be left according to the growth of tobacco plants and soil fertility. Normally, 30% of the tobacco plants in the tobacco field are toppled when the central flowers are in bloom, leaving 20 leaves. In drought, "topping is done twice". The first topping only removes the inflorescence. After rainfall, topping is done again according to the growth of the tobacco plants and the number of leaves to be left is determined. Tobacco fields with high fertility and vigorous growth should be toppled during the peak flowering period and more leaves should be left, while tobacco fields with low fertility and weak growth should be done the opposite. The height of topping and the number of leaves to be left should be based on the standard of whether the tobacco plants can form a "round top". It is necessary to prevent topping too low and leaving too few leaves, and preventing the upper leaves from being too large and thick, with coarse veins and exposed stems, forming an "umbrella-shaped" tobacco plant. It is necessary to ensure that the upper leaves can open the stalks and pieces. After topping, artificial branch removal or chemical bud inhibitors are used to inhibit buds. During the maturity period, it is ensured that there are no flowers in the tobacco fields and no messy branches on the tobacco plants. The removed flower branches and tobacco branches are cleared out of the tobacco fields for centralized treatment.

[0160] (7) Tobacco field plant protection: prevent and control viral diseases and root and stem diseases;

[0161] Viral disease prevention and control includes:

[0162] s1. Virus-free seedling production: During seedling raising, follow the operating procedures, fully disinfect the seedling trays and greenhouses, set up insect-proof nets, hang insect-attracting boards in the greenhouses, disinfect the operating equipment during thinning and leaf cutting, and prohibit smoking in the seedling greenhouses to reduce the spread of viral diseases on tobacco seedlings;

[0163] s2. Agricultural control: Antiviral agents should be sprayed before field operations. According to the principle of treating healthy plants first and then diseased plants, prevent artificial infection when digging seedlings, weeding, and removing film to build up soil. Diseased tobacco fields should be cleared, soiled, and top-dressed in a timely manner. Diseased and damaged leaves should be removed from the tobacco fields in a timely manner, and sprayed with pesticides;

[0164] s3. Chemical control: 1 day before transplanting, spray 3000 times diluted 3% supersensitive protein microparticles on the seedbed, and 7 days after transplanting, spray once with 4000 times diluted, and spray the third time during the clustering stage or the early stage of virus disease;

[0165] When the disease occurs in the field, use 20% morpholinguanidine hydrochloride wettable powder 2000 times liquid, and use trace elements at the same time, spray once every 7 days for 3 times in a row, and add trace elements according to magnesium, zinc, and boron. The mass concentration of each element is 0.25% magnesium, 0.5% boron, and 0.3% zinc;

[0166] Root and tuber disease control includes the following:

[0167] s4. Prevention and control at the seedling stage: Strengthen the disinfection of seedling trays and seedling greenhouses, and use the substrate mixing technology to add biological agents to the substrate in a certain proportion, stir evenly and then raise seedlings;

[0168] s5. Agricultural control: Rotate crops with gramineous crops for more than three years; plough and sun-dry in winter; build high ridges and plant tobacco deep, with the ridge height above 25cm; timely tillage and weeding, remove film and cultivate soil, and drain water after rain; timely remove diseased plants and disinfect the soil around diseased plants;

[0169] s6. Biological control: Use biological agents to prevent the occurrence of root and stem diseases, and apply charcoal-based organic fertilizer at a rate of 200 kg / mu. When transplanting, pour soluble biological agents into the holes along with water. From the clumping stage to the beginning of vigorous growth, mix the biological agents into fully fermented soy milk and use them for root irrigation.

[0170] s7. Chemical control: Observe the occurrence of the disease. At the early stage of the disease, find the diseased center plant and spray the stem base of the center plant and 15 surrounding tobacco plants with pesticides once every 8 days for two consecutive times;

[0171] For black shank disease, use 68% water-dispersible granules of AMF·Mancozeb. For root rot, use 800 times diluted 70% methyl thiophanate wettable powder by spraying the base of the stem or irrigating the roots.

[0172] Biological agents include Trichoderma harzianum, Bacillus subtilis, and Paenibacillus polymyxa;

[0173] The biological agent is injected into the hole with water, and the mass percentage of the biological agent used is 5%, and the injection volume is 15mL per plant;

[0174] The mass ratio of the biological agent to the fully fermented soy milk is 1:10;

[0175] The root irrigation volume was 8 mL per plant;

[0176] Among them, fungicides cannot be applied within one week before and after the application of biological agents.

[0177] (8) Harvesting:

[0178] Maturity: Yu Nong Xiang 201 has medium leaf thickness;

[0179] The lower leaves are harvested early when they are ripe and yellowish in color;

[0180] The middle leaves are harvested when they are mature. The leaves turn yellow, 2 / 3 of the main veins turn white and shiny, the leaves droop, and the angle between the stems and leaves increases.

[0181] For the upper leaves, when mature spots appear on the leaf surface and the main and branch veins turn white, and when they are fully mature, the upper 6 leaves can be harvested at one time.

[0182] (9) Tobacco leaf baking:

[0183] Early stage of yellowing: after the oven is ignited, the temperature rises at a rate of 1h / ℃ until the dry bulb temperature reaches 38℃ and the wet bulb temperature reaches 37℃, and the temperature is kept stable for 50-60 hours;

[0184] Middle stage of yellowing: Raise the dry bulb temperature to 40℃ at a rate of 2h / ℃, maintain the wet bulb temperature at 37℃, and keep the temperature stable for about 15 hours;

[0185] Late yellowing stage: Raise the dry bulb temperature to 42°C at a rate of 2h / °C, maintain the wet bulb temperature at 37°C, and keep the temperature steady for 12-18 hours;

[0186] Early stage of color fixation: increase the dry bulb temperature to 45℃ and the wet bulb temperature to 38℃ at a rate of 2h / ℃, and keep the temperature stable for 12 hours;

[0187] Late color fixation: Raise the temperature to 54°C at 2h / °C, adjust the wet-bulb temperature to 38.5°C-39.5°C, and keep the temperature stable for 36 hours;

[0188] Early stage of drying: raise the temperature to 60℃ at 1h / ℃, adjust the wet bulb temperature to 41℃, and keep the temperature stable for 12 hours;

[0189] Late stage of drying: raise the temperature to 68℃ at 1h / ℃, adjust the wet-bulb temperature to 42℃, and keep the temperature steady for 26 hours until the main vein and tobacco stem are completely dry.

[0190] Example 2

[0191] Based on Example 1, the spraying concentration of the spray fertilizer is calculated by weight percentage as follows: 0.8% potassium dihydrogen phosphate, 0.8% potassium sulfate, 0.8% potassium nitrate, and the rest is water.

[0192] The biological agent is injected into the hole with water, and the mass percentage of the biological agent used is 5%, and the injection volume is 16mL per plant;

[0193] The mass ratio of the biological agent to the fully fermented soy milk is 1:12;

[0194] The root irrigation volume was 9 mL per plant.

[0195] Example 3

[0196] Based on Example 1, the spraying concentration of the spray fertilizer is calculated by weight percentage as follows: 1.0% potassium dihydrogen phosphate, 1.0% potassium sulfate, 1.0% potassium nitrate, and the rest is water.

[0197] The biological agent is injected into the hole with water, and the mass percentage of the biological agent used is 5%, and the injection volume is 20mL per plant;

[0198] The mass ratio of the biological agent to the fully fermented soy milk is 1:15;

[0199] The root irrigation volume was 10 mL per plant.

[0200] Comparative Example 1:

[0201] On the basis of Example 1, no sesame cake fertilizer was added to the fertilizer, and no topdressing by spraying fertilizer was performed.

[0202] Comparative Example 2:

[0203] On the basis of Example 1, the biological bacterial agent is not mixed into the fully fermented soy milk for root irrigation from the clumping stage to the vigorous growth stage.

[0204] test:

[0205] This experiment adopted a split-plot design, with each experimental plot having an area of ​​66m 2 100 tobacco plants were planted in each test area. The plants were managed and planted according to the methods of the embodiment and the comparative example. After the plants were harvested, the yield was counted and the yield per mu was calculated.

[0206] The three-stage baking process was used for baking; the samples were collected from the top six tobacco leaves of each treatment:

[0207] Conventional chemical composition determination The samples were dried at 50°C, ground and sieved (pore size 0.25 mm) to retain the samples. 0.25 g of each leaf length section sample was weighed and the conventional chemical composition of the tobacco leaf samples was determined using an AAⅢ continuous flow chemical analyzer (produced by BRAN+LUEBBE, Germany). The results are shown in Table 1. The determination of water-soluble sugars was based on the standard YC / T159-2002; the determination of total alkaloids was based on the standard YC / T160-2002; and the determination of chlorine was based on the standard YC / T162-2011.

[0208] Table 1

[0209] Total sugar % Nicotine% chlorine% Example 1 20.10 3.56 0.65 Example 2 20.00 3.61 0.69 Example 3 20.13 3.58 0.67 Comparative Example 1 19.55 3.32 0.87 Comparative Example 2 19.36 3.39 0.72

[0210] It can be seen from Table 1 that the tobacco leaves grown by the method of the present invention not only have suitable chemical component content, but also several main components can be coordinated with each other, thereby significantly improving the taste of the tobacco leaves.

[0211] Sensory quality evaluation

[0212] Sensory index measurement The upper six leaves obtained in the examples and comparative examples were cut into 0.12 mm tobacco shreds, rolled into single-material cigarettes, and the moisture was balanced for 48 hours. The sensory quality was evaluated according to the standard "YC / T138-1998 Sensory Evaluation Method for Tobacco and Tobacco Products", as shown in Table 2:

[0213] Table 2

[0214] Fragrance Aroma volume Miscellaneous gas Momentum Smoke concentration Aftertaste Example 1 6.8 6.9 6.2 6.2 6.0 6.4 Example 2 6.5 6.6 6.1 6.5 6.3 6.6 Example 3 6.7 6.3 6.4 6.4 6.1 6.3 Comparative Example 1 6.0 6.1 6.5 6.0 5.8 6.0 Comparative Example 2 5.3 5.7 5.9 5.5 5.2 5.6

[0215] It can be seen from Table 2 that the sensory evaluation results reflect the smoking quality of tobacco leaves. The overall sensory quality of the tobacco leaves grown by the method of the present invention is characterized by rich and full tobacco aroma, sufficient aroma volume, good aroma quality, strong smoke concentration, moderate strength, small irritation, comfortable aftertaste, light miscellaneous smell, high overall sensory quality, and can meet the requirements of cigarette formulas.

[0216] The yield per mu of each embodiment was compared with that of the comparative example, and the results are shown in Table 3.

[0217] Table 3

[0218] Yield per mu / kg Example 1 154.9 Example 2 155.8 Example 3 155.3 Comparative Example 1 146.2 Comparative Example 2 140.9

[0219] It can be seen from Table 3 that the method of the present invention can significantly increase the per-acre yield of tobacco leaves and improve economic benefits after planting.

[0220] Although the present invention has been disclosed as above by the embodiments, it is not intended to limit the present invention. Any person skilled in the art may make various choices and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention is limited by the claims and their equivalents.

Claims

1. A cultivation and production technology for a flue-cured tobacco variety Yu Nong Xiang 201, characterized in that: The following steps are involved: (1) Tobacco field selection: Choose land with medium or higher fertility; (2) Winter ploughing and ridging: Ridging should be done from the end of December of the previous year to January of the following year, preferably after snowfall and clear weather. (3) Sowing period: Sowing should be concentrated from February 25 to March 5 of the following year, and greenhouse preparation should be done before sowing; (4) Scientific transplanting: including the selection of transplanting time, planting density, and transplanting methods in accordance with local conditions; (5) Balanced fertilization: insist on combining organic and inorganic fertilizers, combining basal fertilizer with topdressing, combining nitrogen, phosphorus, potassium with trace elements, and fertilizing at a time consistent with the fertilizer requirements of tobacco plants; (6) Field management: including tillage and weeding, film removal and soil cultivation, water-saving irrigation, structure optimization, and topping and leaf retention; (7) Tobacco field plant protection: prevent and control viral diseases and root and stem diseases; (8) Harvesting: Harvesting tobacco leaves from different parts according to their maturity; (9) Baking: Follow the "three-stage" baking plan.

2. The cultivation and production technology of the flue-cured tobacco variety Yu Nong Xiang 201 according to claim 1, characterized in that: In step (3), the greenhouse preparation work includes reinforcement of greenhouse facilities, substrate fumigation, and tray disinfection; wherein the temperature in the greenhouse is controlled at 20-26°C.

3. The cultivation and production technology of the flue-cured tobacco variety Yu Nong Xiang 201 according to claim 1, characterized in that: In step (4), The transplanting time is divided into regular transplanting time and seedling transplanting time under film. The regular transplanting time is from April 20 to May 1 of the following year; the seedling transplanting time under film is from April 10 to April 15 of the following year. The planting density is 1.3 meters in row and 0.6-0.7 meters in plant spacing; The transplanting method comprises the following steps: selecting robust tobacco seedlings for transplanting, checking the seedlings in time for replanting 7-10 days after the transplanting, and watering the weak seedlings and small seedlings with eccentric water and applying eccentric fertilizer.

4. The cultivation and production technology of the flue-cured tobacco variety Yu Nong Xiang 201 according to claim 1, characterized in that: In step (5), the amount of fertilizer applied is determined as follows: for medium-fertility tobacco fields: that is, plots with a quick-acting nitrogen content of 45-70 mg / kg, or a plateau with a wheat yield of 400-500 kg / mu or a mountainous and hilly area with a wheat yield of 200-3000 kg / mu; for plateaus, 3-3.5 kg of pure nitrogen is applied per mu, and for mountainous and hilly areas, 4-4.5 kg of pure nitrogen is applied per mu; Specific fertilization methods include: (51) Base fertilizer: Before ridge formation, apply 40 kg of charcoal cake fertilizer, 5 kg of potassium sulfate and 25 kg of tobacco fertilizer per mu in narrow strips along the center line of the ridge body; 20 kg of zinc sulfate, 1 kg of borax, 5 kg of magnesium hydroxide and 50 g of ammonium molybdate as base fertilizer at one time; (52) Hole fertilizer: When transplanting, mix 5 kg of tobacco fertilizer, 2 kg of potassium nitrate and 10 kg of charcoal cake fertilizer per mu with the soil and apply it in the holes to prevent excessive concentration of fertilizers, which may cause root burn and seedling injury. (53) Top dressing: 3 kg of potassium nitrate should be applied by drip irrigation at the clumping stage or dissolved in water for irrigation. 15 kg of potassium sulfate should be applied by drip irrigation three times, at 45 days, 60 days, and 75 days after transplanting.

5. The cultivation and production technology of the flue-cured tobacco variety Yu Nong Xiang 201 according to claim 4 is characterized in that: In step (53), topdressing specifically comprises: (531) Topdressing: When tobacco plants enter the vigorous growth period, apply the remaining 20% ​​of potassium sulfate fertilizer. Make a hole 10-15 cm deep 10-15 cm away from the stem circumference, pour the fertilizer solution into the hole in a fixed amount or inject it with a back injection device, and then seal the hole with soil. When the tobacco plants reach maturity, apply the remaining 30% of potassium sulfate fertilizer; (532) Foliar fertilization: When tobacco plants show signs of nutrient deficiency or severe imbalance, foliar fertilization should be applied. Foliar fertilization is mainly carried out during the clustering stage, vigorous growth stage and dome stage. Spraying should be carried out after 4 p.m. on a sunny or cloudy day without wind. Spraying should be done on both sides. The concentration of the fertilizer applied is calculated by weight percentage as follows: potassium dihydrogen phosphate 0.50-1.0%, potassium sulfate 0.5-1.0%, potassium nitrate 0.5-1.0%, and the rest is water.

6. The cultivation and production technology of the flue-cured tobacco variety Yu Nong Xiang 201 according to claim 1, characterized in that: Step (6) is specifically as follows: a. Intertillage and weeding: Intertillage should be frequent and deep, combined with soiling, and the ridge should be enlarged to promote the main root to grow deep and the lateral root to expand. The first time is after the seedlings are returned, specifically 10 days after planting, with shallow intertillage and small soiling; the second time is before the tobacco plants enter the clustering stage, specifically 20-25 days after planting, with large intertillage and high soiling combined with fertilization; the third intertillage is carried out 5-7 days before topping, to remove weeds, eliminate compaction, and remove 1-2 old leaves near the ground to ensure that the tobacco leaves near the ground are well ventilated and light-permeable; b. Remove the film and add soil: Remove the film and add soil 35-45 days after transplanting. When adding soil, the loose soil on the surface of the soil should be closely combined with the base of the stem. After adding soil, the furrows should be straight, flat, and free of weeds. The surface of the soil should be tile-shaped and 30 cm high. All the remaining film removed should be removed from the tobacco field and centrally processed. Add soil in time after removing the film; c. Water-saving irrigation: Water-saving irrigation is carried out according to the water demand of tobacco plants at different growth stages and in combination with climatic conditions. No watering is done during the seedling stage and the early stage of clustering. In severe cases where tobacco leaves wilt and drought cannot be recovered in the afternoon, point irrigation or a small amount of irrigation is used for alternate rows. Pay attention to drought during the vigorous growth period and irrigate enough "vigorous growth water". Fertilizer is adjusted with water to keep soil moisture at 80-85% of the maximum water holding capacity. During the maturity period, dome water and mature yellowing water are irrigated according to the soil moisture conditions to keep soil moisture at 50-60% of the maximum water holding capacity. d. Optimize structure: (1) Secondary optimization: Before and after the tobacco plants bud, clean the 4-5 bottom leaves below, and top the plants when 50% of the central flowers are open. After topping, remove the lower leaves that are under-illuminated, poorly developed, and of poor quality. When harvesting and baking the upper leaves, discard the 2-3 top leaves that are poorly developed, poorly opened, and of poor quality. During the tobacco leaf harvesting process, the diseased and damaged leaves should be promptly cleaned out of the tobacco field and buried in a pit; (2) Removal of unsuitable tobacco leaves before roasting: Fresh tobacco is classified when it is braided, and fresh tobacco leaves of poor quality are further removed, including unripe leaves, overripe leaves, and diseased leaves; e. Topping and leaving leaves: The topping period and the number of leaves to be left should be determined according to the growth of tobacco plants and soil fertility. Normally, 50% of the tobacco plants in the tobacco field should be topped when the central flowers are in bloom, leaving 20-22 leaves. In drought, "topping is done twice". The first topping only removes the inflorescence. After rainfall, topping is done again according to the growth of the tobacco plants and the number of leaves to be left should be determined. Tobacco fields with high fertility and vigorous growth should be topped during the peak flowering period and more leaves should be left. Tobacco fields with low fertility and weak growth should be done the opposite. The height of topping and the number of leaves to be left should be based on the standard of whether the tobacco plants can form a "round top". It is necessary to prevent topping too low and leaving too few leaves, and the upper leaves being too large and thick, with coarse veins and exposed stems, forming "umbrella-shaped" tobacco plants. It is necessary to ensure that the upper leaves can open the stalks and pieces. After topping, artificial branch removal or chemical bud inhibitors are used to inhibit buds. In the mature period, it is ensured that there are no flowers in the tobacco fields and no messy branches on the tobacco plants. The removed flower branches and tobacco branches are promptly cleared out of the tobacco fields for centralized treatment.

7. The cultivation and production technology of the flue-cured tobacco variety Yu Nong Xiang 201 according to claim 1, characterized in that: In step (7), Viral disease prevention and control includes: s1. Virus-free seedling production: During seedling raising, follow the operating procedures, fully disinfect the seedling trays and greenhouses, set up insect-proof nets, hang insect-attracting boards in the greenhouses, disinfect the operating equipment during thinning and leaf cutting, and prohibit smoking in the seedling greenhouses to reduce the spread of viral diseases on tobacco seedlings; s2. Agricultural control: Antiviral agents should be sprayed before field operations. According to the principle of treating healthy plants first and then diseased plants, prevent artificial infection when digging seedlings, weeding, and removing film to build up soil. Diseased tobacco fields should be cleared, soiled, and top-dressed in a timely manner. Diseased and damaged leaves should be removed from the tobacco fields in a timely manner, and sprayed with pesticides; s3. Chemical control: 1-3 days before transplanting, spray 3000 times diluted 3% supersensitive protein microparticles on the seedbed, and spray once with 4000-5000 times diluted 7-10 days after transplanting. Spray for the third time during the clustering stage or the early stage of virus disease. When the disease occurs in the field, use 20% morpholino hydrochloride wettable powder 2000 times, or 20% morpholino copper acetate wettable powder 800--1200 times, or 8% ningnanmycin aqueous solution 1200--1600 times, and use trace elements at the same time, spray once every 7--10 days; Root and tuber disease control includes the following: s4. Prevention and control at the seedling stage: Strengthen the disinfection of seedling trays and seedling greenhouses, and use the substrate mixing technology to add biological agents to the substrate in a certain proportion, stir evenly and then raise seedlings; s5. Agricultural control: Rotate crops with gramineous crops for more than three years; plough and sun-dry in winter; build high ridges and plant tobacco deep, with the ridge height above 25cm; timely tillage and weeding, remove film and cultivate soil, and drain water after rain; timely remove diseased plants and disinfect the soil around diseased plants; s6. Biological control: Use biological agents to prevent root and stem diseases, apply charcoal-based organic fertilizer 200kg / mu; when transplanting, pour soluble biological agents into the holes with water; from the cluster stage to before vigorous growth, mix the biological agents into fully fermented soybean milk for root irrigation; s7. Chemical control: Observe the occurrence of the disease. At the early stage of the disease, find the diseased center plant and spray the stem base of the center plant and 10-20 tobacco plants around it with pesticides once every 7-10 days for two times in a row. For black shank disease, use 68% carbendazim·mancozeb water dispersible granules, or 600-800 times diluted 72% carbendazim·mancozeb wettable powder, or 600-800 times diluted 50% flumorph·ethylene aluminum wettable powder. For root rot, use 800-1000 times diluted 70% methyl thiophanate wettable powder by spraying the base of the stem or irrigating the roots.

8. The cultivation and production technology of the flue-cured tobacco variety Yu Nong Xiang 201 according to claim 7, characterized in that: The biological microbial agent comprises: Trichoderma harzianum, Bacillus subtilis, and Bacillus polymyxa; the biological microbial agent is injected into the holes along with water, and the mass percentage of the biological microbial agent used is 5%, and the injection amount is 15-20 mL per plant; the mass ratio of the biological microbial agent to the fully fermented soybean milk is 1:10-15; the root injection amount is 8-10 mL per plant; wherein, the bactericide cannot be applied within one week before and after the application of the biological microbial agent.

9. The cultivation and production technology of the flue-cured tobacco variety Yu Nong Xiang 201 according to claim 7, characterized in that: The harvesting of step (8) is specifically as follows: Maturity: Yu Nong Xiang 201 has medium leaf thickness; The lower leaves are harvested early when they are ripe and yellowish in color; The middle leaves are harvested when they are mature. The leaves turn yellow, 2 / 3--4 / 5 of the main veins turn white and shiny, the leaves droop, the groove under the leaf tip rolls inward, and the angle between the stem and the leaves increases. For the upper leaves, when the surface turns white and shiny, some leaves show mature spots, the leaf tips curl inward, and appear slightly scorched, and the main and branch veins turn white and shiny, and when they are fully mature, the upper 4-6 leaves can be harvested at one time.

10. The cultivation and production technology of the flue-cured tobacco variety Yu Nong Xiang 201 according to claim 7, characterized in that: The baking of step (9) comprises: (1) Early stage of yellowing: After the oven is ignited, the temperature rises at a rate of 1h / ℃ until the dry bulb temperature reaches 38℃ and the wet bulb temperature reaches 37℃, and the temperature is kept stable for 50-60 hours; (2) Middle stage of yellowing: Raise the dry-bulb temperature to 40°C at a rate of 2h / °C, maintain the wet-bulb temperature at 37°C, and keep the temperature steady for 15 hours; (3) Late yellowing stage: Raise the dry-bulb temperature to 42°C at a rate of 2h / °C, maintain the wet-bulb temperature at 37°C, and keep the temperature steady for 12-18 hours; (4) Early stage of color fixation: increase the dry bulb temperature to 45°C and the wet bulb temperature to 38°C at a rate of 2h / °C and keep the temperature stable for 12 hours; (5) Late color fixation: Raise the temperature to 54°C at 2h / °C, adjust the wet-bulb temperature to 38.5°C-39.5°C, and keep the temperature stable for 36 hours; (6) Early stage of drying: raise the temperature to 60°C at 1h / °C, adjust the wet-bulb temperature to 41°C, and keep the temperature stable for 12 hours; (7) Late drying stage: Raise the temperature to 68°C at 1h / °C, adjust the wet-bulb temperature to 42°C, and maintain the temperature for 26 hours until the main vein and stem are completely dry.

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