A method of reduced pressure fumigation specifically for control of ephestia cautella and its application

Abstract

The application discloses a fumigation method and device specially used for controlling Indian meal moth adult, adopts fumigation combining with SO2 and a special fumigation device to provide negative pressure, realizes low concentration and short time high efficiency fumigation, not only significantly improves the control efficiency on Indian meal moth larvae, but also realizes effective control on Indian meal moth eggs, pupae and adult, when the product of SO2 concentration and fumigation time is 10000, the pressure is 20kPa and the fumigation time is 20h, the mortality of Indian meal moth eggs, pupae, larvae and adult is 100%. The fumigation method provided by the application is simple, time and labor saving, the fumigation effect is good, the SO2 concentration is low, the quality of dry fruits is ensured, and the method has important practical significance for large-scale storage of dry fruits.

Description

Technical Field

[0001] This invention relates to the field of chemical gas fumigation technology for insect control, and in particular to a decompression fumigation method specifically for the control of Indian moth, as well as its applicable apparatus and applications. Background Technology

[0002] The Indian meal borer (Plodia interpunctella L.) is a major pest during the storage of dried fruits and is one of the most significant pests of stored foods worldwide. It not only affects product quality but also causes serious damage to various processed foods, including grains, flour products, and over 20 different types of nuts and fruits. As a major pest of dried fruits, the Indian meal borer severely impacts quality and causes substantial economic losses, with loss rates reaching 15%-20%, and potentially up to 100% if not treated promptly. In its larval stage, the Indian meal borer can directly penetrate the foil, polyester, and polypropylene films covering the stored products and attach to the surface of dried fruits. As the larvae grow, they spin webs on the surface and inside of the dried fruits, damaging their structure, and leaving excrement and molted skin residue. During the adult stage, females lay over 500 eggs, severely affecting the quality and commercial value of the dried fruits.

[0003] Methyl bromide and phosphine are the main methods for controlling the infestation of Indian meal borer in cereals and their processed products, dried goods, and traditional Chinese medicine. However, methyl bromide severely damages the environment and the ozone layer, and its use has been restricted both domestically and internationally. Phosphine is highly toxic to mammals, and insects have generally developed resistance to it. Since 2015, methyl bromide and phosphine have been gradually phased out in the fumigation of stored grains. High-pressure, high-carbon dioxide fumigation is also an effective way to control pests in stored products. However, most degenerated larvae are not very sensitive to carbon dioxide and require more than 168 hours of treatment to die completely. Furthermore, this method requires sealed containers, making it difficult to apply in large-scale storage. Existing fumigation methods suffer from problems such as cumbersome operation, complex equipment, long processing time, easy deterioration of the quality of stored products, and are not conducive to large-scale field promotion and application. There is an urgent need to find new alternatives to traditional insecticidal fumigants such as methyl bromide and phosphine.

[0004] While existing literature reports methods for controlling Indian meal borer using sulfur dioxide fumigation, these methods primarily target the eggs, larvae, and pupae of the Indian meal borer, with a mortality rate of 80-90%. They are not very effective against adult Indian meal borers. Furthermore, excessively high sulfur dioxide concentrations, excessive sulfur dioxide residues after storage, and prolonged fumigation times all negatively impact the quality of dried fruit storage. Therefore, there is an urgent need for an efficient method to control Indian meal borer, ensuring the storage quality of dried fruit, extending its shelf life, and increasing its commercial value. Summary of the Invention

[0005] To address the problems of traditional fumigation methods such as essential oil fumigation, nitrogen-filled airbag fumigation, phosphine, and carbon dioxide in controlling Indian meal borers, and the need to further improve the control efficiency of sulfur dioxide fumigation at ambient temperature and pressure against Indian meal borer larvae, as well as the technical issues of high sulfur dioxide concentration, long fumigation time, and low efficiency against eggs, pupae, and adults in ambient temperature and pressure fumigation methods, this invention aims to provide a depressurized fumigation method specifically for the control of Indian meal borers, along with its applicable device and application. This method combines depressurized fumigation with SO2, utilizing a dedicated depressurized fumigation device to provide low pressure, achieving low-concentration, short-duration, and highly efficient fumigation. This not only significantly improves the control efficiency against Indian meal borer larvae but also effectively controls Indian meal borer eggs, pupae, and adults. When the product of SO2 concentration and fumigation time is 10000 and the pressure is 20 kPa, the mortality rate of Indian meal borer eggs, pupae, larvae, and adults is 100%. This invention demonstrates that the decompression fumigation method for controlling the Indian eel borer provided by this invention is simple, time-saving, labor-saving, and has a significant fumigation effect. It also results in low sulfur dioxide concentration and low residual sulfur dioxide content, extending the shelf life of dried fruits, ensuring the quality of dried fruits, and increasing the commercial value of dried fruits. This method has important practical significance for the large-scale storage of dried fruits for insect control.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] This invention provides a depressurized fumigation method specifically for the control of Indian meal moth. The depressurized fumigation method specifically includes the following steps: placing a rearing tank containing Indian meal moths into a sealed fumigation container within a depressurized fumigation device, closing the fumigation container, setting the internal pressure of the fumigation container to 20 kPa, injecting sulfur dioxide gas into the fumigation container through a fumigation valve using a needle injection system, controlling the fumigation conditions inside the fumigation container to a temperature of 10-45℃, a humidity of 10-30%, a pressure of 20 kPa, and an SO2 concentration of 250-1000 ppm, and starting sealed fumigation for 4-42 hours.

[0008] The aforementioned pressure-reducing fumigation device includes a fumigation container, a negative pressure generating component, a fumigation introduction component, a monitoring component, and a control component. The fumigation container is used to hold the material to be fumigated. The negative pressure generating component is connected to the interior of the fumigation container and is used to extract gas from inside the fumigation container, creating a negative pressure environment inside. The fumigation introduction component is connected to the interior of the fumigation container and is used to introduce fumigant into the fumigation container. The monitoring component is connected to the interior of the fumigation container and is used to monitor internal parameters. The control component is connected to both the negative pressure generating component and the monitoring component. The negative pressure generating component includes a vacuum pump, the suction end of which is connected to the interior of the fumigation container. The vacuum pump is connected to the fumigation container. An isolation valve is provided to isolate the gas between the fumigation container and the vacuum pump, maintaining a negative pressure environment inside the fumigation container. The fumigation inlet assembly includes a fumigation valve installed on the fumigation container, which connects to an external injection assembly to inject external fumigant into the fumigation container. The monitoring assembly includes a thermometer and hygrometer and a pressure transmitter, both connected to the control assembly. The thermometer and hygrometer monitor the temperature and humidity data inside the fumigation container and transmit the data to the control assembly. The pressure transmitter monitors pressure changes inside the fumigation container and transmits the data to the control assembly. The control assembly includes a control cabinet, which is connected to the vacuum pump, isolation valve, fumigation valve, thermometer and hygrometer, and pressure transmitter.

[0009] The fumigation container is equipped with a pressure balancing component, which is used to balance the pressure environment inside the fumigation container to be the same as the external pressure environment.

[0010] The pressure balancing assembly includes an air inlet valve communicating with the interior of the fumigation container and an opening valve controlled by the air inlet valve. The air inlet valve is used for external gas to enter the fumigation container, and the opening valve is controlled by the control cabinet to control the opening and closing of the air inlet valve.

[0011] The fumigation container is equipped with a fan, which is connected to the control cabinet. The fan is used to agitate the gas inside the fumigation container.

[0012] The fumigation conditions are: temperature 28°C, humidity 25%, pressure 20 kPa, and the product of SO2 concentration and fumigation time is 10000.

[0013] The Indian meal borer is described in its egg, pupa, larva, and adult stages.

[0014] The Indian meal borer mentioned refers to the adult Indian meal borer.

[0015] The present invention further provides an application of a depressurized fumigation method specifically used for the control of Indian moth in the storage of dried apricots.

[0016] Through the above technical solution, the present invention achieves the following technical effects:

[0017] (1) This invention uses fumigation that combines depressurization and SO2. A dedicated depressurization fumigation device is used to provide depressurization, which achieves low-concentration, short-time and high-efficiency fumigation. This not only significantly improves the control efficiency of adult Indian meal borers, but also effectively controls Indian meal borer eggs, pupae and adults. When the product of sulfur dioxide concentration, SO2 concentration and fumigation time is 10000 and the pressure is 20 kPa, the mortality rate of Indian meal borer eggs, pupae, larvae and adults is 100%.

[0018] (2) The reduced-pressure fumigation method for controlling the Indian meal borer, a pest in dried fruit storage, provided by this invention, uses reduced-pressure SO2 as the fumigant and a corresponding technical process to fumigate and protect stored dried fruit from pests. Compared with other physical and chemical methods, reduced-pressure fumigation has advantages such as cost-effectiveness, low residue, good insecticidal effect, easy promotion, short treatment time, low environmental harm, and high safety factor. The effect of reduced-pressure fumigation is significantly better than other fumigation methods. The improved and optimized reduced-pressure fumigation process can maximize the protection of stored dried fruit. Reduced-pressure gas fumigation has the advantages of rapid penetration, low residue, easy control, wide contact area, uniform dispersion, and low residue. It can quickly penetrate into the gaps of the fumigated material and effectively act on the target material, making it an effective insecticidal method. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the overall structure of the pressure-reducing fumigation device used in this invention.

[0020] The components include: 1. Fumigation container; 2. Negative pressure generating component; 21. Vacuum pump; 22. Isolation valve; 3. Fumigation introduction component; 31. Fumigation valve; 4. Monitoring component; 41. Thermometer and hygrometer; 42. Pressure transmitter; 5. Control component; 51. Control cabinet; 6. Pressure balancing component; 61. Inlet valve; 62. Door opening valve; and 7. Fan. Detailed Implementation

[0021] The present invention is illustrated by the following embodiments; however, the present invention is not limited to the following embodiments.

[0022] All raw materials used in this invention can be purchased through public channels, and the equipment and instruments used in the process are all common in the art. The determination methods for all materials, reagents, and instruments selected in this invention are well-known in the art but do not limit the embodiments of this invention. Other well-known reagent kits and equipment can be applied to the embodiments of this invention described below.

[0023] Example 1: A reduced-pressure fumigation method specifically for the control of Indian moth

[0024] This embodiment provides a reduced-pressure fumigation method for controlling the Indian meal borer, a pest in dried fruit storage. The reduced-pressure fumigation method specifically includes the following steps: placing a rearing tank containing the Indian meal borer into a sealed fumigation container within a reduced-pressure fumigation device, closing the fumigation container, setting the internal pressure of the fumigation container to 20 kPa, injecting SO2 gas into the fumigation container through a fumigation valve using a needle injection system, controlling the fumigation conditions inside the fumigation container to a temperature of 10-45℃, a humidity of 10-30%, a pressure of 20 kPa, and an SO2 concentration of 250-1000 ppm, and starting sealed fumigation for 4-42 hours.

[0025] Example 2: A reduced-pressure fumigation device specifically designed for the control of the Indian moth. (See attached diagram.) Figure 1 The following is a detailed description of the specific embodiments of the pressure-reducing fumigation device of the present invention. In the description of the present invention, it should be understood that the terms "center," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention.

[0026] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature; in the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0027] It should be noted that the circuit connections involved in this invention all adopt conventional circuit connection methods and do not involve any innovation.

[0028] like Figure 1 As shown, the pressure-reducing fumigation device includes a fumigation container 1, a negative pressure generating component 2, a fumigation introduction component 3, a monitoring component 4, a control component 5, a pressure balancing component 6, and a fan 7. Wherein:

[0029] Fumigation container 1 is used to hold the material to be fumigated;

[0030] The negative pressure generating component 2 is connected to the inside of the fumigation container 1 and is used to extract the gas inside the fumigation container 1 to create a negative pressure environment inside the fumigation container 1. The negative pressure generating component 2 includes a vacuum pump 21, the suction end of the vacuum pump 21 is connected to the inside of the fumigation container 1, and an isolation valve 22 is provided at the connection between the vacuum pump 21 and the fumigation container 1. The isolation valve 22 is used to isolate the gas between the fumigation container 1 and the vacuum pump 21 to maintain a negative pressure environment inside the fumigation container 1.

[0031] The fumigation introduction component 3 is connected to the interior of the fumigation container 1 and is used to introduce fumigant into the fumigation container 1. The fumigation introduction component 3 includes a fumigation valve 31 disposed on the fumigation container 1. The fumigation valve 31 is used to connect to an external injection component so that external fumigant is injected into the fumigation container 1 through the fumigation valve 31.

[0032] The monitoring component 4 is connected to the inside of the fumigation container 1 and is used to monitor the internal parameters of the fumigation container 1. The monitoring component 4 includes a thermometer and hygrometer 41 and a pressure transmitter 42, which are respectively connected to the control component 5. The thermometer and hygrometer 41 is used to monitor the temperature and humidity data inside the fumigation container 1 and transmit it to the control component 5. The pressure transmitter 42 is used to monitor the pressure change data inside the fumigation container 1 and transmit it to the control component 5.

[0033] The control component 5 is connected to the negative pressure generating component 2 and the monitoring component 4 respectively. The control component 5 includes a control cabinet 51, which is connected to the vacuum pump 21, the isolation valve 22, the fumigation valve 31, the thermometer and hygrometer 41 and the pressure transmitter 42 respectively.

[0034] The fumigation container 1 is equipped with a pressure balancing component 6, which is used to balance the pressure environment inside the fumigation container 1 to be the same as the external pressure environment. The pressure balancing component 6 includes an air inlet valve 61 that communicates with the inside of the fumigation container 1 and an opening valve 62 that is controlled and connected to the air inlet valve 61. The air inlet valve 61 is used for external gas to enter the fumigation container 1, and the opening valve 62 is controlled and connected to the control cabinet 51 to control the opening and closing of the air inlet valve 61.

[0035] The fumigation container 1 is equipped with a fan 7, which is connected to the control cabinet 51. The fan 7 is used to agitate the gas inside the fumigation container 1.

[0036] The working method of the above embodiment is as follows: the material to be fumigated is placed in the fumigation container 1, the air inlet valve 61 and the fumigation valve 31 are closed, the vacuum pump 21 and the isolation valve 22 are turned on to evacuate the inside of the fumigation container 1, and the pressure inside the fumigation container 1 is judged according to the pressure data provided by the pressure transmitter 42 to determine whether the pressure inside the fumigation container 1 has reached the set pressure. Then, the vacuum pump 21 and the isolation valve 22 are turned off to maintain a negative pressure environment inside the fumigation container 1. Then, without affecting the negative pressure environment inside the fumigation container 1, the gaseous fumigant is injected into the fumigation container 1 through the fumigation valve 31 using the external injection component. The fan 7 is turned on to stir the gaseous fumigant so that the gaseous fumigant is evenly distributed inside the fumigation container 1, and the depressurized fumigation begins. After the fumigation is completed, the air inlet valve 61 is opened by the door opening valve 62 to allow external air to enter the inside of the fumigation container 1 through the air inlet valve 61, so that the pressure environment inside the fumigation container 1 is the same as the external pressure environment. The fumigated material can then be taken out.

[0037] The specific models of the above electronic components are not specifically specified; any commercially available ordinary products can be selected, as long as they can meet the usage requirements of this invention.

[0038] Example 3: A reduced-pressure fumigation method specifically for the control of Indian moth

[0039] Based on Examples 1-2, this embodiment provides a reduced-pressure fumigation method for controlling the Indian meal borer, a pest in dried fruit storage. The fumigation conditions are a temperature of 28°C, a humidity of 25%, a pressure of 20 kPa, and an SO2 concentration multiplied by the fumigation time of 10000.

[0040] Example 4: A reduced-pressure fumigation method specifically for the control of Indian moth

[0041] Based on Examples 1-2, this embodiment provides a reduced-pressure fumigation method for controlling the Indian meal borer, a pest in dried fruit storage. The fumigation conditions are: temperature 10°C, humidity 10%, pressure 20 kPa, and SO2 concentration multiplied by fumigation time is 2000.

[0042] Example 5: A reduced-pressure fumigation method specifically for the control of Indian moth

[0043] Based on Examples 1-2, this embodiment provides a reduced-pressure fumigation method for controlling the Indian meal borer, a pest in dried fruit storage. The fumigation conditions are a temperature of 45°C, a humidity of 30%, a pressure of 20 kPa, and an SO2 concentration multiplied by the fumigation time of 10000.

[0044] Example 6: A reduced-pressure fumigation method specifically for the control of Indian moth

[0045] Based on Examples 1-2, this embodiment provides a reduced-pressure fumigation method for controlling the Indian meal borer, a pest in dried fruit storage. The fumigation conditions are a temperature of 40°C, a humidity of 20%, a pressure of 20 kPa, and an SO2 concentration multiplied by the fumigation time of 8000.

[0046] Example 7: Optimization of a reduced-pressure fumigation method specifically for the control of Indian moth

[0047] Based on Examples 1-6, this embodiment optimizes the parameters of the method provided by the present invention. This experiment adopts the concept of C×T (ppm×h) product, and under reduced pressure, combined with SO2 and fumigation time, three SO2 concentrations (250, 500, 1000 ppm) were set to evaluate the effects of six C×T (0, 2000, 4000, 6000, 8000, 10000) on different life stages of Indian meal borer. Three replicates were set for each C×T. The specific statistical data of the experimental data of different life stages of Indian meal borer are shown in Table 1.

[0048] Table 1: Mortality of Indian meal borer due to different C×T values ​​after reduced pressure SO2 fumigation

[0049]

[0050]

[0051] Note: The data in the table are the mean ± standard error of three replicates. Different lowercase letters after the data in the same column indicate that the differences at different time points at the same concentration were statistically significant (P<0.05) according to Duncan's test.

[0052] Table 1 shows that the mortality rate of *Paecilomyces albuminosus* at different stages under different decompression concentrations increased with increasing C×T values ​​over time, and the time to death from fumigation gradually decreased with increasing concentration. During the egg stage, when SO2 concentrations were 250, 500, and 1000 ppm, and C×T values ​​reached 6000, 6000, and 2000 respectively, the egg mortality rate increased significantly. When C×T values ​​reached 10000, 8000, and 8000, the egg stage could be completely controlled. During the larval stage, the mortality rate was low when the C×T value was 2000. When the C×T value increased from 4000 ppm×h to 6000 ppm×h, the larval mortality rate increased significantly. When the C×T value reached a maximum of 10000 for all three concentrations, the larval mortality rate reached 100%. The effect of different C×T values ​​on the emergence rate of pupae during the pupal stage of SO2 fumigation was investigated. Increasing the C×T value from 4000 ppm×h to 6000 ppm×h significantly increased pupal mortality. At an SO2 concentration of 500 ppm and a C×T value of 8000, pupae were the first to be completely killed. At the maximum C×T value of 10000 across all three concentrations, complete control of each stage of the Indian meal borer was achieved. In the adult stage, at the lowest C×T value of 2000, adult mortality increased rapidly. At a concentration of 1000, a C×T value of 6000 completely killed adults. At a C×T value of 8000 across all three tested concentrations, the mortality rate of the tested adults reached 100%.

[0053] For each stage of the Indian meal moth, a lower C×T value determined a lower mortality rate compared to a higher C×T value. Specifically, when C×T increased from 4000 ppm×h to 6000 ppm×h, the mortality rate of all subjects at each stage of the Indian meal moth significantly increased. Significant differences in mortality rates were observed among the three different C×T concentrations fumigated under reduced pressure. A specific trend was found between SO2 concentration and fumigation time, but the percentage mortality rate differed for each concentration and time combination at each tested C×T value (P<0.05). During fumigation, a C×T value of 10000 was found to kill the Indian meal moth at every stage.

[0054] Table 2: Effects of different SO2 concentrations on the life-stage LT of Indian meal borer at different life stages 50and LT 95 The influence of value

[0055]

[0056] Table 2 shows the LT values ​​of different life stages of *Paecilomyces cerevisiae* treated with different SO2 concentrations under reduced pressure according to the present invention. 50 and LT 95 The values ​​and confidence intervals (h) for fumigation treatments with different SO2 concentrations (1000, 500, 250 ppm) under reduced pressure were determined. The adult stage of the Indian meal moth was the most sensitive; under reduced pressure SO2 fumigation (250, 500, 1000 ppm), its LT... 50 The values ​​were 10.70h, 6.11h, and 2.21h, respectively, representing the LT during the oviposition period. 50 The LT50 values ​​for the pupal, larval, and juvenile stages were 14.08h, 7.07h, and 2.90h, respectively. The LT50 values ​​for the larval, juvenile, and juvenile stages were 15.80h, 8.08h, and 3.36h, respectively. 50 The corresponding times were 19.13h, 10.30h, and 4.38h. These data indicate that, using the method of this invention, the sensitivity of different life stages of the Indian meal borer to different SO2 concentrations is: adult > egg > pupa > larva.

[0057] Example 8: Comparison of different methods for controlling the Indian eel borer

[0058] This embodiment, based on embodiments 1-7, compares the reduced-pressure fumigation method provided by the present invention with existing fumigation methods. The object of treatment is dried apricot fruit. The present invention uses the parameters provided in embodiment 3. Control 1 is the method of controlling pistachio navel orange larvae and pupae by short-time sulfur dioxide fumigation of blueberry fruit disclosed in the literature (“Blueberry fruit quality and control of blueberry maggot (Rhagoletis mendax Curran) larvae after fumigation with sulfur dioxide”, PATRICK J. ABLI PDF, RUFUS ISAACA R, et al., 179(2021)111568). Control 2 is the method of controlling pistachio navel orange larvae and pupae by short-time sulfur dioxide fumigation of blueberry fruit disclosed in the literature (“Curing raisins with sulfur dioxide suppresses population growth of Indian meal moth, Plodia interpunctella (Hubner) (Lepidoptera: Pyralidae)”, Rezanejad Sirus, Journal). The optimal process for treating Indian orange moth larvae by atmospheric pressure sulfur dioxide fumigation, as disclosed in the *Journal of Asia-Pacific Entomology* (2022-01-29), was compared with the control method provided in the published literature ("Efficacy and sorption of sulfur dioxide as a fumigant for control of navel orangeworm (Amyelois transitella) on stored pistachios", Liu YB., *Journal of Stored Products Research*, 2023, 102:102-109) for treating navel orange moth eggs, larvae, and pupae. The main investigation focused on the effects of different methods on the mortality rate, SO2 concentration, fumigation time, and sulfur dioxide residue after 90 days of storage (referring to the acid-base titration method in the determination of sulfur dioxide in food according to GB5009.34-2022 National Food Safety Standard). Specific data are shown in Table 3.

[0059] Table 3: Effects of different methods on Indian meal borer

[0060]

[0061] As shown in Table 3, the reduced-pressure sulfur dioxide fumigation method for controlling Indian meal borer provided by this invention is simple, time-saving, labor-saving, and has excellent fumigation effect. Furthermore, the sulfur dioxide concentration is low, and the residual sulfur dioxide level is minimal after 90 days of storage, meeting national standards. In contrast, apricot dried fruit treated with atmospheric pressure sulfur dioxide fumigation and rapid fumigation methods exceeded the standards after 90 days of storage. This demonstrates that the method provided by this invention not only uses less sulfur dioxide but also ensures that the residual sulfur dioxide level meets standards after 90 days of storage, guaranteeing the quality of the dried fruit. Simultaneously, this invention's method can use a relatively low concentration of sulfur dioxide to completely control all life stages of the Indian meal borer in a short time, achieving full-stage control. By adjusting the pressure and treatment time, the concentration and duration of sulfur dioxide gas during fumigation can be more precisely controlled to achieve highly efficient insecticidal effects.

[0062] In summary, the reduced-pressure fumigation method and its applicable device for controlling adult Indian meal borers provided by this invention combine reduced pressure with SO2 fumigation. Utilizing a dedicated reduced-pressure fumigation device, it achieves low-concentration, short-duration, and highly efficient fumigation. This not only significantly improves the control efficiency against adult Indian meal borers but also effectively controls their eggs, pupae, and adults. When the product of sulfur dioxide concentration, SO2 concentration, and fumigation time is 10000, and the pressure is 20 kPa, the mortality rate of Indian meal borer eggs, pupae, larvae, and adults is 100%. This demonstrates that the reduced-pressure sulfur dioxide fumigation method for controlling Indian meal borers provided by this invention is simple, time-saving, and labor-saving, with significant fumigation effects. Furthermore, the low sulfur dioxide concentration and minimal residual sulfur dioxide extend the shelf life of dried fruits, ensuring their quality and increasing their commercial value. This method has significant practical implications for large-scale insect control in the storage of dried fruits.

[0063] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A reduced pressure fumigation method specific for control of Ephestia cautella (Walker) characterized in that, The reduced pressure fumigation method specifically comprises the following steps: placing a sitotroga cerealella rearing tank containing sitotroga cerealella in a closed fumigation container of a reduced pressure fumigation device, closing the fumigation container, setting the internal pressure of the fumigation container to 20 kPa, injecting sulfur dioxide gas into the fumigation container through a fumigation valve by needle injection, and controlling the fumigation conditions in the fumigation container, including a temperature of 10-45 ℃, a humidity of 10-30%, a pressure of 20 kPa, and a SO2 concentration of 250-1000 ppm, and starting the closed fumigation for 4-42 h; The reduced pressure fumigation device comprises a fumigation container (1), a negative pressure generating assembly (2), a fumigation introduction assembly (3), a monitoring assembly (4), and a control assembly (5). The fumigation container (1) is used for placing materials to be fumigated. The negative pressure generating assembly (2) is in communication with the inside of the fumigation container (1) and is used for pumping out the gas in the fumigation container (1) to form a negative pressure environment in the fumigation container (1). The fumigation introduction assembly (3) is in communication with the inside of the fumigation container (1) and is used for introducing a fumigant into the fumigation container (1). The monitoring assembly (4) is in communication with the inside of the fumigation container (1) and is used for monitoring the parameters in the fumigation container (1). The control assembly (5) is respectively connected with the negative pressure generating assembly (2) and the monitoring assembly (4). The negative pressure generating assembly (2) comprises a vacuum pump (21), and the suction end of the vacuum pump (21) is in communication with the inside of the fumigation container (1). A cutoff valve (22) is arranged at the connection between the vacuum pump (21) and the fumigation container (1), and the cutoff valve (22) is used for cutting off the gas between the fumigation container (1) and the vacuum pump (21) to maintain a negative pressure environment in the fumigation container (1). The fumigation introduction assembly (3) comprises a fumigation valve (31) arranged on the fumigation container (1), and the fumigation valve (31) is used for being connected with an external injection assembly to inject an external fumigant into the fumigation container (1) through the fumigation valve (31). The monitoring assembly (4) comprises a temperature and humidity meter (41) and a pressure transmitter (42) connected with the control assembly (5). The temperature and humidity meter (41) is used for monitoring the temperature and humidity data in the fumigation container (1) and transmitting the data to the control assembly (5). The pressure transmitter (42) is used for monitoring the pressure change data in the fumigation container (1) and transmitting the data to the control assembly (5). The control assembly (5) comprises a control cabinet (51) connected with the vacuum pump (21), the cutoff valve (22), the fumigation valve (31), the temperature and humidity meter (41), and the pressure transmitter (42). A pressure balancing assembly (6) is arranged on the fumigation container (1), and the pressure balancing assembly (6) is used for balancing the internal pressure environment of the fumigation container (1) with the external pressure environment. The pressure balance assembly (6) in the reduced pressure fumigation device includes an air inlet valve (61) in communication with the inside of the fumigation container (1) and an open door valve (62) in control connection with the air inlet valve (61), the air inlet valve (61) is used for external gas to enter the fumigation container (1), and the open door valve (62) is in control connection with the control cabinet (51) and is used for controlling the opening and closing of the air inlet valve (61).

2. A reduced pressure fumigation method specifically for control of Ephestia cautella (Walker) as claimed in claim 1, wherein, The fumigation container (1) is provided with a fan (7) in the reduced pressure fumigation device, the fan (7) is connected with the control cabinet (51), and the fan (7) is used for stirring the gas in the fumigation container (1).

3. A reduced pressure fumigation method specifically for control of Ephestia cautella (Walker) as claimed in claim 1, wherein, The fumigation condition temperature is 28 DEG C, the humidity is 25%, the pressure is 20kPa, and the product of the concentration of SO2 and the fumigation time is 10000.

4. A reduced pressure fumigation method specifically for control of Ephestia cautella (Walker) as claimed in claim 1, wherein, The indian meal moth is an adult.

5. The application of the reduced pressure fumigation method for preventing and treating the indian meal moth in claim 1 in the storage of apricot dried fruits.

Images