Production method of selenium-enriched annona squamosa
By applying sodium selenite pentahydrate solution through irrigation and foliar spraying during the flower bud differentiation and flowering and fruit setting stages of custard apples, the problem of low selenium content in custard apples was solved, resulting in a significant increase in fruit selenium content and improved quality, making it suitable for large-scale promotion.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- YUNNAN AGRICULTURAL UNIVERSITY
- Filing Date
- 2026-02-09
- Publication Date
- 2026-05-05
AI Technical Summary
The selenium content in existing custard apple cultivation is generally low, and there is a lack of systematic selenium enrichment production methods, resulting in low selenium utilization, high costs, complex operations, and unstable selenium content, making it difficult to achieve standardized and large-scale production.
Sodium selenite pentahydrate solution was applied by irrigation and foliar spraying during the flower bud differentiation and flowering and fruit setting stages of custard apple. The concentration for irrigation was 750 mg/L, and the concentration for foliar spraying was 50 mg/L. The timing and method of selenium application were optimized in conjunction with conventional water and fertilizer management and pest and disease control.
It significantly increases the selenium content of fruits to 49µg/kg, meeting national standards, improves fruit quality, enhances antioxidant capacity, is easy to operate, suitable for large-scale promotion, and has a high selenium utilization rate.
Smart Images
Figure CN121970642A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of agricultural planting technology and relates to a method for producing selenium-enriched custard apples. Background Technology
[0002] Selenium (Se) is an essential trace element for the human body, possessing various physiological functions such as anti-oxidation, immune enhancement, and prevention of cancer and cardiovascular diseases. However, the human body cannot synthesize selenium on its own and must obtain it through food. Approximately 72% of my country's land area is selenium-deficient or low-selenium, resulting in generally low selenium content in most crops and fruits, making it difficult to meet the body's daily needs. Therefore, increasing the selenium content of crops through agricultural techniques has become one of the important directions in functional agriculture research.
[0003] Custard apple (Annona atemoya L.), also known as sugar apple or Buddha's head fruit, is a famous tropical fruit. Its flesh is rich in nutrients, including amino acids, vitamins, minerals, and various active substances such as custard apple lactone and alkaloids, which possess excellent antioxidant, antitumor, and antibacterial activities. Currently, custard apple cultivation is still mainly based on conventional management, resulting in generally low selenium content and failing to realize its potential as a selenium-rich functional food.
[0004] In existing technologies, the main methods for selenium enrichment in crops are soil application and foliar spraying. However, research on selenium enrichment technology for fruit trees such as custard apples is limited, and there is a lack of systematic optimization schemes for the timing, concentration, and method of selenium application. Existing methods often suffer from low selenium utilization, high costs, complex operations, and unstable selenium content, making it difficult to achieve standardized and large-scale production.
[0005] Therefore, there is an urgent need to develop a simple, cost-effective, and stable selenium-content production method for custard apples that meets national selenium standards, in order to meet market demand for high-quality selenium-enriched fruits and enhance the added value and competitiveness of custard apples. Summary of the Invention
[0006] The technical problem to be solved by this invention is to provide a selenium-enriched custard apple production method that is simple to operate, cost-controllable, has stable selenium content, and can significantly improve fruit quality, addressing the issues of generally low selenium content and lack of systematic selenium-enriched production methods in existing custard apple cultivation.
[0007] To solve the above-mentioned technical problems, the present invention provides a method for producing selenium-enriched custard apples, comprising the following steps: S1. During the flower bud differentiation period of custard apple, apply selenium solution to the custard apple trees three times, with an interval of about 30 days between each application. S2. During the flowering and fruit setting period of custard apple, spray the custard apple trees with selenium solution twice, with an interval of about 30 days between each spray. S3. Simultaneously apply the irrigation treatment of step S1 and the spraying treatment of step S2 to the custard apple trees.
[0008] More preferably, the selenium solution is a sodium selenite pentahydrate solution, with an irrigation concentration of approximately 750 mg / L and a spraying concentration of 50 mg / L.
[0009] A further preferred method involves excavating a circular fertilization trench around the tree canopy, injecting the selenium solution evenly into the trench, and then covering it with soil after it has seeped in.
[0010] A further preferred method is to use a sprayer to evenly spray the selenium solution onto the entire fruit tree.
[0011] More preferably, the irrigation treatment is carried out once each during the flower bud differentiation period, the flowering and fruit setting period, and the fruit enlargement period.
[0012] More preferably, the spraying treatment is carried out once during the flowering and fruit setting period and once during the fruit enlargement period.
[0013] More preferably, the method also includes routine water and fertilizer management and pest and disease control during the selenium treatment.
[0014] Compared with the prior art, the present invention has the following beneficial effects: Firstly, it significantly increases selenium content. By applying selenium solutions of approximately 750 mg / L and 50 mg / L through irrigation and foliar spraying, this invention significantly increases the selenium content of 'Custard Apple' custard apples, achieving a selenium content of approximately 49 µg / kg, far exceeding the control group and within the national standard range (10-50 µg / kg). After applying selenium solution to the soil, the selenium content of the custard apple fruit shows a significant increase, meeting the raw material standards for selenium-enriched products. Furthermore, this fruit can be used as a basis for the research and development and production of selenium-enriched foods and related derivatives.
[0015] Secondly, it improves the overall quality of the fruit: This invention not only increases the selenium content and antioxidant capacity of the fruit, but also improves the overall quality of the fruit, including taste and nutritional value, thus enhancing the market competitiveness of custard apples.
[0016] Thirdly, this invention employs an irrigation method, which has a long-lasting effect, continuously supplying selenium while also considering crop growth and stress resistance. The foliar spraying method is simple and easy to implement, requires fewer applications, saves time and labor, and is suitable for large-scale application. Combining irrigation and foliar application methods improves the overall utilization rate of selenium, covering the selenium needs of crops throughout their entire growth cycle. Attached Figure Description
[0017] Figure 1 The effects of different selenium application methods on the intrinsic quality of leaves of 'Custard Apple Pineapple' (where AD represents experimental data from four groups of samples). Figure 2 This study investigated the effects of different selenium application methods on the total selenium content of 'Custard Apple' custard apple fruit. Detailed Implementation
[0018] The following detailed description, in conjunction with the accompanying drawings and specific embodiments, provides a further detailed explanation of the production method of selenium-enriched custard apples proposed by the present invention. The advantages and features of the present invention will become clearer from the following description. It should be noted that the accompanying drawings are all in a very simplified form and use non-precise proportions, and are only used to facilitate and clarify the illustration of the embodiments of the present invention. The same or similar reference numerals in the drawings represent the same or similar parts.
[0019] Example: A method for producing selenium-enriched custard apples 1. Experimental materials and locations Experimental location: Custard apple orchard in a dry-hot valley agricultural science and technology demonstration park in Yuanjiang County, Yuxi City, Yunnan Province.
[0020] Experimental materials: Select robust 3-year-old 'Pineapple Custard Apple' custard apple trees with uniform growth.
[0021] Selenium source: Sodium selenite pentahydrate (analytical grade).
[0022] Main equipment: manual sprayer (20L), ring trenching tool, atomic fluorescence spectrometer, ultraviolet-visible spectrophotometer, etc.
[0023] Protective equipment: Laboratory personnel should wear gloves, goggles, masks, etc. during operation.
[0024] 2. Experimental Design The selected custard apple trees were randomly divided into 4 groups of 3 trees each, with 3 replicates. The specific groupings are as follows: CK group (control group): The entire process was carried out using clean water for irrigation and spraying.
[0025] Group B (Irrigation Group): Only soil irrigation with selenium solution was performed.
[0026] Group C (Spraying Group): Only foliar spraying of selenium solution was performed.
[0027] Group D (irrigation + foliar spraying): Soil irrigation and foliar spraying were carried out simultaneously.
[0028] 3. Preparation of selenium solution Selenium solution for irrigation: Weigh 30g of sodium selenite pentahydrate, dissolve it in 40L of water, and stir thoroughly until completely dissolved to obtain a selenium solution with a mass concentration of approximately 750mg / L.
[0029] Spraying with selenium solution: Weigh 0.3g of sodium selenite pentahydrate, dissolve it in 6L of water, and stir thoroughly until completely dissolved to obtain a selenium solution with a mass concentration of 50mg / L.
[0030] 4. Implementation process (1) Irrigation treatment (for groups B and D) First application: At the early stage of flower bud differentiation of custard apple, dig a circular trench about 15-20cm deep around the outer edge of the tree canopy projection, pour the prepared selenium solution evenly into the trench, and cover it with soil after the solution has penetrated.
[0031] Second irrigation: Repeat the above operation during the flowering and fruit setting period (around mid-May).
[0032] Third irrigation: Repeat the above operation during the fruit enlargement period (around mid-June).
[0033] Each application should be spaced approximately 30 days apart, and a total of three applications should be made.
[0034] (2) Spraying treatment (for groups C and D) First application: During the flowering and fruit setting period (around mid-May), choose a windless or light-windy early morning or evening, and use a sprayer to evenly spray the selenium solution onto the entire plant's leaves and young fruit surface, until the leaves are moist but not dripping.
[0035] Second spraying: Repeat the above spraying operation during the fruit enlargement period (around mid-June).
[0036] Each spraying should be applied approximately 30 days apart, for a total of two sprayings.
[0037] (3) Control group (CK group) At the same time point, irrigation and spraying operations were carried out with the same amount of clean water.
[0038] (4) Other management During the trial, all groups maintained consistent field management practices, including irrigation, fertilization, and pest and disease control, in accordance with standard custard apple cultivation and management practices.
[0039] 5. Sample Collection and Measurement Sampling time: Sampling was carried out at the fruit ripening stage after all treatments were completed.
[0040] Sampling method: Collect 10 healthy leaves and 3 mature fruits from the middle of the canopy of each tree, mix them together and use them as the test samples for this replication.
[0041] 5.1. Leaf and fruit sample collection: After all irrigation and spraying treatments were completed, leaf samples and mature fruit samples of each group of custard apples were collected, and the selenium content of the custard apple leaves was tested.
[0042] 5.2 Effects of selenium solution on antioxidant enzymes in the leaves of 'Pineapple Custard Apple' nutmeg. like Figure 1As shown, the irrigation measures in treatment groups B and C had a greater impact on the POD (peroxidase) of 'Pineapple Custard Apple' custard apple.
[0043] like Figure 1 As shown, the irrigation and foliar spraying measures in treatment groups B, C, and D all affected the production of CAT (catalase) in 'Pineapple Custard Apple' custard apples, with treatment group B having the greatest impact.
[0044] like Figure 1 As shown, the irrigation measures in treatment group C had the greatest impact on SOD (superoxide dismutase) in 'Pineapple Custard Apple' custard apple.
[0045] like Figure 1 As shown, the irrigation and spraying measures of treatment groups B, C, and D all affected the production of MDA (malondialdehyde) in 'Pineapple Custard Apple' custard apples, with treatment group D having the greatest impact.
[0046] 5.3. Effect of selenium solution on selenium content in 'Pineapple Custard Apple' fruit As shown in Figure 2, the irrigation and foliar spraying methods used in treatment groups B, C, and D all had a positive effect on increasing the total selenium content of 'Pineapple Custard Apple' fruits. The selenium content detected in the control group fruits is presumably due to indirect diffusion from the selenium treatment in the environment, but this content was the lowest among all treatments. The results indicate that different selenium application methods can effectively increase the selenium accumulation in custard apple leaves and fruits, and soil application has the most significant effect on promoting selenium absorption by custard apples.
[0047] Results and Analysis Selenium content accumulation: The total selenium content in the custard apple fruits of all treatment groups (B, C, D) was significantly higher than that of the control group. Among them, the selenium content of the fruits in group D (irrigation + foliar spraying) was the highest, reaching 0.049 mg / kg, which meets the national standard for selenium-enriched agricultural products of fruits (selenium content 10-50 µg / kg).
[0048] Enhanced antioxidant capacity: Compared with the control group, all selenium treatments increased the activity of POD, CAT and SOD in the leaves to varying degrees and reduced the MDA content, indicating that the antioxidant capacity and stress resistance of the plants were enhanced.
[0049] Overall effect evaluation: Group D (irrigation + foliar spraying) showed a synergistic effect in increasing selenium content and improving antioxidant indicators, and the effect was better than single irrigation or foliar spraying treatments.
[0050] This embodiment applies selenium to 'Pineapple Custard Apple' custard apples using different methods, significantly increasing the selenium content and altering the plant's antioxidant capacity. This method is of great significance for increasing the added value of fruit products, meeting consumer demand, and increasing farmers' income.
[0051] The above description is merely a description of preferred embodiments of the present invention and is not intended to limit the scope of the present invention in any way. Any changes or modifications made by those skilled in the art based on the above disclosure shall fall within the protection scope of the claims.
Claims
1. A method for producing selenium-enriched custard apples, characterized in that, Includes the following steps: S1. During the flower bud differentiation period of custard apple, apply selenium solution to the custard apple trees three times, with an interval of about 30 days between each application. S2. During the flowering and fruit setting period of custard apple, spray the custard apple trees with selenium solution twice, with an interval of about 30 days between each spray. S3. Simultaneously apply the irrigation treatment of step S1 and the spraying treatment of step S2 to the custard apple trees.
2. The method for producing selenium-enriched custard apples according to claim 1, characterized in that, The selenium solution is a sodium selenite pentahydrate solution, with an irrigation concentration of approximately 750 mg / L and a spraying concentration of 50 mg / L.
3. The method for producing selenium-enriched custard apples according to claim 2, characterized in that, The method of applying selenium solution is as follows: dig a circular fertilization trench around the tree canopy, inject the selenium solution evenly into the trench, and cover it with soil after it has seeped in.
4. The method for producing selenium-enriched custard apples according to claim 1, characterized in that, The method of spraying selenium solution is as follows: use a sprayer to evenly spray the selenium solution onto the entire fruit tree.
5. The method for producing selenium-enriched custard apples according to claim 1, characterized in that, The irrigation treatment was carried out once each during the flower bud differentiation period, the flowering and fruit setting period, and the fruit enlargement period.
6. The method for producing selenium-enriched custard apples according to claim 1, characterized in that, The spraying treatment was carried out once during the flowering and fruit setting period and once during the fruit enlargement period.
7. The method for producing selenium-enriched custard apples according to claim 1, characterized in that, The method also includes routine water and fertilizer management and pest and disease control during the selenium treatment.