Prediction method and system for overripening stage of middle tobacco leaves of tobacco plant

Abstract

The present invention relates to the technical field of overripening stage prediction of tobacco leaves, and particularly to a prediction method and system for an overripening stage of middle tobacco leaves of a tobacco plant. The method comprises: acquiring a topping date of a tobacco plant to be predicted and a ripening date of middle tobacco leaves, and calculating the number of days from the topping date to the ripening date of the middle tobacco leaves; and inputting the number of days from the topping date to the ripening date of the middle tobacco leaves into a preset prediction model, outputting the number of days from the topping date to an overripening date of the middle tobacco leaves of the tobacco plant to be predicted, and on the basis of the number of days from the topping date to the overripening date of the middle tobacco leaves, predicting a date on which the middle tobacco leaves of the tobacco plant to be predicted reach an overripe state, wherein the prediction model is constructed on the basis of the law of the number of days from the topping date to the ripening date of the middle tobacco leaves and the number of days from the topping date to the overripening date of the middle tobacco leaves of the tobacco plant in terms of time amount. The present invention can accurately predict the arrival time of the overripening stage of the middle tobacco leaves of the tobacco plant, and has practical guidance significance for determining the optimal harvesting deadline of the tobacco leaves and guaranteeing the quality of the tobacco leaves.

Description

Method and system for predicting overripe period of middle flue-cured tobacco leaves Technical Field

[0001] The present invention relates to the technical field of tobacco leaf over-ripe period prediction, and in particular to a method and system for predicting the over-ripe period of middle tobacco leaves in flue-cured tobacco. Background Art

[0002] The over-maturity period of tobacco leaves refers to the critical period when the appearance and internal quality of tobacco leaves begin to decline and decay significantly after they have grown and developed in the field and have undergone technological maturity, and are no longer suitable for harvesting and processing.

[0003] Tobacco leaves need to be harvested after they mature but before they become overripe, otherwise their quality will significantly decline. Predicting the overripe stage in advance is crucial for production practice. It provides crucial information for planning and managing various production resources (such as harvesting personnel, transportation capacity, storage space, supporting production materials, and curing and processing capacity) during tobacco harvesting, helping to avoid quality losses caused by harvesting overripe leaves.

[0004] The current method for determining tobacco leaf overripeness involves first determining whether a leaf is "overripe" based on its appearance, such as the degree of yellowing on the leaf surface and changes in leaf shape. This method relies on manual, on-site qualitative evaluation to produce results. It characterizes, records, and describes past events, and can be used to summarize past events, but it cannot predict when the "overripe" stage will occur. Therefore, a method and system for predicting the overripe stage of mid-flue tobacco leaves is urgently needed.

[0005] Summary of the Invention

[0006] The purpose of the present invention is to provide a method for predicting the over-ripe period of the middle tobacco leaves of flue-cured tobacco, which can accurately predict when the over-ripe period of the middle tobacco leaves of flue-cured tobacco will arrive, ensure the quality of tobacco leaves harvested, and has guiding significance for production practice.

[0007] To achieve the above object, the present invention provides the following solutions:

[0008] A method for predicting the overripe period of middle flue-cured tobacco leaves comprises:

[0009] Obtain the dates of "topping" and "maturity of middle tobacco leaves" for the flue-cured tobacco to be predicted, and calculate the number of days from "topping to maturity of middle tobacco leaves";

[0010] The number of days from "topping to middle tobacco leaves maturing" is input into a preset prediction model, the number of days from "topping to middle tobacco leaves over-maturity" of the flue-cured tobacco to be predicted is output, and the date on which the middle tobacco leaves of the flue-cured tobacco to be predicted reach an over-maturity state is predicted based on the number of days from "topping to middle tobacco leaves maturing" and "topping to middle tobacco leaves over-maturity" of the flue-cured tobacco is predicted, wherein the prediction model is constructed based on the regularity of the time quantity between the number of days from "topping to middle tobacco leaves maturing" and the number of days from "topping to middle tobacco leaves over-maturity" of the flue-cured tobacco.

[0011] Optionally, the process of constructing the prediction model based on the temporal regularity of the number of days from "topping to middle tobacco leaves becoming mature" and "topping to middle tobacco leaves becoming overripe" in flue-cured tobacco includes:

[0012] Set different levels of cultivation influencing factors to cultivate tobacco sample groups with different growth and development progress;

[0013] Record the "topping" date of the flue-cured tobacco sample population, as well as the date when the flue-cured tobacco sample population "reaches maturity" and "reaches overmaturity", and obtain the number of days from "topping to middle tobacco leaves maturity" and "topping to middle tobacco leaves overmaturity" for the flue-cured tobacco sample population;

[0014] The prediction model is constructed based on the regression relationship between the number of days from "topping to maturity of middle tobacco leaves" and the number of days from "topping to over-maturity of middle tobacco leaves" of the flue-cured tobacco sample population.

[0015] Optionally, the cultivation influencing factors include fertilization, number of leaves left and planting density.

[0016] Optionally, constructing the prediction model based on the regression relationship between the number of days from "topping to middle tobacco leaves maturity" and the number of days from "topping to middle tobacco leaves overripe" of the flue-cured tobacco sample population includes:

[0017] Constructing an index based on the number of days from "topping to middle tobacco leaves maturity" and "topping to middle tobacco leaves overripe" of the flue-cured tobacco sample population;

[0018] The regression relationship between each of the two indicators is calculated, and the regression relationship formula with the largest fitting degree involving both the number of days from "topping to maturity of the middle tobacco leaves" and the number of days from "topping to over-maturity of the middle tobacco leaves" is screened out, i.e., the prediction model.

[0019] Optionally, the indicators include: the number of days from "topping - middle tobacco leaves mature" and the number of days from "topping - middle tobacco leaves over-mature", as well as derived indicators based on the number of days from "topping - middle tobacco leaves mature" and the number of days from "topping - middle tobacco leaves over-mature".

[0020] Optionally, the derived indicators include: "Topping - Middle Tobacco Leaves Over-mature" Days - "Topping - Middle Tobacco Leaves Mature" Days", "Topping - Middle Tobacco Leaves Mature" Days + "Topping - Middle Tobacco Leaves Over-mature", "Topping - Middle Tobacco Leaves Over-mature" Days / "Topping - Middle Tobacco Leaves Mature" Days, "Topping - Middle Tobacco Leaves Mature" Days × "Topping - Middle Tobacco Leaves Over-mature", "Topping - Middle Tobacco Leaves Mature" Days × "Topping - Middle Tobacco Leaves Mature" Days, "Topping - Middle Tobacco Leaves Over-mature" Days × "Topping - Middle Tobacco Leaves Mature" Days.

[0021] Optionally, the prediction model is: d2 = (d1 - 7.9236) / 0.6783

[0022] Among them, d2 is the number of days from "topping to over-ripening of the middle tobacco leaves", and d1 is the number of days from "topping to ripening of the middle tobacco leaves".

[0023] To further achieve the above-mentioned object, the present invention also provides a prediction system for the over-ripe period of the middle tobacco leaves of flue-cured tobacco, comprising: a collection module, a prediction module;

[0024] The acquisition module is used to obtain the dates of "topping" and "maturity of middle tobacco leaves" of the flue-cured tobacco to be predicted, and calculate the number of days from "topping to maturity of middle tobacco leaves";

[0025] The prediction module is used to input the number of days from "topping to maturity of middle tobacco leaves" into a preset prediction model, output the number of days from "topping to over-maturity of middle tobacco leaves" of the flue-cured tobacco to be predicted, and predict the date on which the middle tobacco leaves of the flue-cured tobacco to be predicted will reach an over-mature state based on the number of days from "topping to over-maturity of middle tobacco leaves"; wherein the prediction model is constructed based on the regularity of the time quantity between the number of days from "topping to maturity of middle tobacco leaves" and the number of days from "topping to over-maturity of middle tobacco leaves" of flue-cured tobacco.

[0026] The beneficial effects of the present invention are:

[0027] The present invention uses the number of days from "topping to middle tobacco leaves maturing" and the number of days from "topping to middle tobacco leaves being overripe" as basic variable indicators, and based on this, constructs a series of derived indicators with different calculation relationships, and then explores the time law of the number of days from "topping to middle tobacco leaves maturing" and the number of days from "topping to middle tobacco leaves being overripe", establishes a regression relationship expression, constructs a prediction model, and verifies through error calculation that the prediction model of the present invention is reasonable, applicable, and effective, and can accurately predict when the tobacco leaves will be overripe, ensure the quality of tobacco leaves harvested, has guiding significance for production practice, and can provide important decision-making for the planning and operation of various production resources in tobacco leaves harvesting work, and avoid quality loss caused by harvesting overripe tobacco leaves. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0029] FIG1 is a flow chart of a method for predicting the over-ripe stage of middle flue-cured tobacco leaves according to an embodiment of the present invention;

[0030] Figure 2 is a schematic diagram of the number of days from "topping to middle tobacco leaves mature" and "topping to middle tobacco leaves overripe" in the flue-cured tobacco of an embodiment of the present invention, wherein d1 is the number of days from "topping to middle tobacco leaves mature" and d2 is the number of days from "topping to middle tobacco leaves overripe";

[0031] FIG3 is a regression analysis diagram of the index relationship formula with the largest degree of fit screened out according to an embodiment of the present invention;

[0032] FIG4 is a comparative analysis diagram of the predicted value and the measured value of the number of days for “topping—overripeness of the middle tobacco leaves” according to an embodiment of the present invention. DETAILED DESCRIPTION

[0033] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0034] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0035] "Maturity" and "overmaturity" are two distinct physiological stages of tobacco leaf growth and development under specific environmental conditions. They represent the orderly expression of tobacco leaf genes and the gradual development of physiological and biochemical processes, driven by the combined effects of environmental conditions and the regulatory mechanisms of tobacco leaf gene expression. They are the manifestation of objective biological laws of growth and development in tobacco leaves. The two are interconnected throughout the tobacco leaf life cycle, exhibiting a causal relationship and a temporal order. "Accumulated temperature" in the environment refers to the sum of the average daily temperatures over a specific period of time. It is an important indicator for studying the relationship between temperature and the growth rate of biological organisms, and can be used to characterize the impact of temperature on the growth and development of organisms in terms of both intensity and duration. It is clear that accumulated temperature during tobacco leaf maturation and aging is directly proportional to the number of growing days. Therefore, the number of days tobacco leaves grow in the field can be used as an independent variable influencing tobacco leaf senescence, and a model of its relationship with senescence can be established.

[0036] This embodiment examines the number of days from the "topping" of the tobacco plant to the time when the fresh tobacco leaves in the middle reach "maturity", and the number of days from the "topping" to the time when the fresh tobacco leaves in the middle reach "senescence"; using these as basic variable indicators, a series of derivative indicators with different calculation relationships are constructed to explore the laws of the two in terms of time quantity and establish a regression relationship expression; and then based on the regression relationship expression, the over-maturity period of the tobacco leaves is predicted according to the maturity period of the tobacco leaves.

[0037] This embodiment provides a method for predicting the over-ripe stage of middle flue-cured tobacco leaves, as shown in FIG1 , comprising:

[0038] Obtain the dates of "topping" and "maturity of middle tobacco leaves" for the flue-cured tobacco to be predicted, and calculate the number of days from "topping to maturity of middle tobacco leaves";

[0039] The number of days from "topping to maturity of the middle tobacco leaves" is input into a preset prediction model, and the number of days from "topping to over-maturity of the middle tobacco leaves" of the flue-cured tobacco to be predicted is output. The date on which the middle tobacco leaves of the flue-cured tobacco to be predicted reach an over-mature state is predicted based on the number of days from "topping to maturity of the middle tobacco leaves" and "topping to over-maturity of the middle tobacco leaves". The prediction model is constructed based on the regularity of the time quantity between the number of days from "topping to maturity of the middle tobacco leaves" and the number of days from "topping to over-maturity of the middle tobacco leaves" of the flue-cured tobacco.

[0040] "Topping" refers to cutting off the entire inflorescence when the top buds of the tobacco plant are fully open to terminate its reproductive growth.

[0041] "Mature middle tobacco leaves" means that the leaves in the middle of the tobacco plant have reached the standard of maturity for harvesting. Its appearance characteristics are that 6-7% of the tobacco leaf surface area is yellow-green to light yellow, and 2 / 3 of the main veins turn white and shiny.

[0042] "Topping - Middle Tobacco Leaves Mature" refers to the time from "topping" to "maturity of middle tobacco leaves" of the tobacco plant.

[0043] The specific process of building a prediction model is as follows:

[0044] Step 1. Cultivating flue-cured tobacco sample groups at different overmaturity stages;

[0045] Fertilization, number of leaves left, and tobacco planting density are important factors influencing the maturity and overmaturity of tobacco leaves. To obtain tobacco leaf samples with different overmaturity stages, this study selected three important cultivation practices: fertilization rate, number of leaves left, and planting density. The setting levels of each factor are shown in Table 1.

[0046] Table 1

[0047] The Box-Behnken experimental design method was used to develop a three-factor, three-level response surface experimental design with a total of 16 treatments, as shown in Table 2.

[0048] Table 2

[0049] The experimental field is located in Dazhai Township, Gulin County, Luzhou City, Sichuan Province. The soil is primarily composed of yellow and purple soils with a heavy clay texture. Soil physical and chemical properties include a pH of 6.49, organic matter of 3.11 g / kg, alkaline nitrogen of 140.93 mg / kg, available phosphorus of 40.06 mg / kg, and available potassium of 121 mg / kg. The flue-cured tobacco variety used in the experiment was Zhongchuan 208. Tobacco seedlings were transplanted at the appropriate time, with 60 plants planted in each treatment plot. Field management measures other than the treatment factors were implemented according to the high-quality flue-cured tobacco cultivation and management plan.

[0050] Step 2. Record the inspection of relevant indicators of tobacco leaves during the over-ripening period;

[0051] When the tobacco plants in each treatment entered the budding and topping stage, topping was performed to remove the inflorescence at the top of the tobacco plants. Twenty tobacco plants with normal growth were randomly selected from each treatment plot, and their topping dates were recorded. Then, the appearance characteristics of their middle tobacco leaves (9-11 leaves) were inspected every day, and the dates on which they reached "maturity" and "overmaturity" were determined and recorded. As shown in Figure 2, d1 is the number of days from "topping to maturity of the middle tobacco leaves"; d2 is the number of days from "topping to overmaturity of the middle tobacco leaves".

[0052] The data of the 20 materials recorded in each treatment were averaged and used, and the results are shown in Table 3. The values ​​of the two indicators d1 and d2 were obtained through actual field surveys. "d2-d1", "d1+d2", "d2 / d1", "d1×d2", "d1×d1", and "d2×d2" are all derived indicators generated by calculation.

[0053] Table 3

[0054] Step 3. The expression of the number of days d2 for "topping--middle tobacco leaves are overripe" is established, i.e., the prediction model is established;

[0055] In order to explore the relationship between the number of days from topping to the maturity of the middle tobacco leaves (d1) and the number of days from topping to the over-maturity of the middle tobacco leaves (d2), the regression relationship between these indicators was calculated in order to screen out the relationship formula that involves both indicators (d1) and (d2) and has the highest degree of fit. The expressions reflecting the regression relationship between d1 and d2 based on the indicators in Table 3 are shown in Table 4. The degree of fit R of each regression equation in the table is 1. 2 The range of values ​​is [0.5573-0.9966]. Most of the R 2 The value is above 0.8, which indicates that there is an obvious and regular correlation between the two indices d1 and d2 in the process of tobacco leaf aging, showing a high correlation; 2 The maximum value of the relationship is y = 1.6783x + 7.9236, R 2=0.9966, where the x variable is d2 and the y variable is d1+d2. The regression analysis is shown in Figure 3.

[0056] This shows that among the indicators involved, this relationship can most accurately reflect the relationship between d1 and d2.

[0057] Substituting the independent variable x for "d2" and the dependent variable y for "d1+d2", we get the following expression: d1+d2=1.6783×d2+7.9236 d1-7.9236=0.6783×d2

[0058] The final formula, i.e. the prediction model, is: d2 = (d1-7.9236) / 0.6783.

[0059] This results in a relationship with d1 as the independent variable and d2 as the dependent variable. After knowing the number of days d1 from "topping to middle tobacco leaves maturing" through field surveys, this relationship can be used to determine the number of days d2 from "topping to middle tobacco leaves becoming overripe," further predicting the specific date when the leaves will reach overripeness in the future.

[0060] Table 4

[0061] To further optimize the technical solution, this embodiment also provides a prediction system for the over-ripe period of the middle tobacco leaves of flue-cured tobacco, comprising: a collection module, a prediction module;

[0062] The acquisition module is used to obtain the number of days from "topping to maturity of middle tobacco leaves" of the flue-cured tobacco to be predicted;

[0063] The prediction module is used to input the number of days from "topping to maturity of middle tobacco leaves" into a preset prediction model, output the number of days from "topping to over-maturity of middle tobacco leaves" of the flue-cured tobacco to be predicted, and predict the date when the middle tobacco leaves of the flue-cured tobacco to be predicted will reach the over-maturity state based on the number of days from "topping to over-maturity of middle tobacco leaves"; wherein the prediction model is constructed based on the regularity of the time quantity of the number of days from "topping to maturity of middle tobacco leaves" and the number of days from "topping to over-maturity of middle tobacco leaves" of flue-cured tobacco.

[0064] To verify the application effect of this embodiment, the measured value d1 in Table 5 is substituted into the prediction model to obtain the predicted value d2', and the relative error between d2' and d2 is calculated. The results are shown in Table 5 below, and the comparative analysis of d2' and d2 is shown in Figure 4.

[0065] Table 5

[0066] The relative errors between all predicted values ​​d2' and d2 are between -1.96% and 5%, and most of them are within ±2%. The root mean square error (RMSE) is used to measure the error size of the prediction results. Where yi is the actual value, is the predicted value, and n is the number of samples. When the root mean square error is less than 2, it indicates that the model is reasonable and usable. The RMSE of the prediction model in this embodiment is 0.9354, which is less than 2, proving that the obtained model has excellent prediction effect and excellent usability.

[0067] The embodiments described above are merely descriptions of preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Without departing from the design concept and spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should fall within the scope of protection determined by the claims of the present invention.

Claims

1. A method for predicting the over-ripe stage of middle tobacco leaves, characterized in that: include: Obtain the dates of "topping" and "maturity of middle tobacco leaves" for the flue-cured tobacco to be predicted, and calculate the number of days from "topping to maturity of middle tobacco leaves"; The number of days from "topping to middle tobacco leaves maturing" is input into a preset prediction model, and the number of days from "topping to middle tobacco leaves over-maturity" of the flue-cured tobacco to be predicted is output, and the date on which the middle tobacco leaves of the flue-cured tobacco to be predicted reach an over-maturity state is predicted based on the number of days from "topping to middle tobacco leaves maturing" and "topping to middle tobacco leaves over-maturity" of the flue-cured tobacco. The prediction model is constructed based on the regularity of the time quantity between the number of days from "topping to middle tobacco leaves maturing" and the number of days from "topping to middle tobacco leaves over-maturity" of the flue-cured tobacco.

2. The method for predicting the overripe stage of the middle tobacco leaves of flue-cured tobacco according to claim 1, characterized in that: The process of constructing the prediction model based on the time pattern of the number of days from "topping to middle tobacco leaves becoming mature" and "topping to middle tobacco leaves becoming over-mature" in flue-cured tobacco includes: Set different levels of cultivation influencing factors to cultivate tobacco sample groups with different growth and development progress; Record the "topping" date of the flue-cured tobacco sample population, as well as the date when the flue-cured tobacco sample population "reached maturity" and "reached overmaturity", and obtain the number of days from "topping to middle tobacco leaves maturity" and "topping to middle tobacco leaves overmaturity" for the flue-cured tobacco sample population; The prediction model is constructed based on the regression relationship between the number of days from "topping to middle tobacco leaves maturity" and the number of days from "topping to middle tobacco leaves overripe" of the flue-cured tobacco sample population.

3. The method for predicting the over-ripe stage of the middle part of the flue-cured tobacco leaves according to claim 2, characterized in that: The cultivation influencing factors include fertilization, number of leaves left and planting density.

4. The method for predicting the over-ripe stage of the middle part of the flue-cured tobacco leaves according to claim 2, characterized in that: The prediction model is constructed based on the regression relationship between the number of days from "topping to middle tobacco leaves maturity" and the number of days from "topping to middle tobacco leaves overripe" of the flue-cured tobacco sample population, including: Constructing an index based on the number of days from "topping to middle tobacco leaves maturity" and "topping to middle tobacco leaves overripe" of the flue-cured tobacco sample population; The regression relationship between each of the two indicators is calculated, and the regression relationship formula with the largest fitting degree involving both the number of days from "topping to maturity of middle tobacco leaves" and the number of days from "topping to over-maturity of middle tobacco leaves" is screened out, i.e., the prediction model.

5. The method for predicting the over-ripe stage of the middle tobacco leaves of flue-cured tobacco according to claim 4, characterized in that: The indicators include: the number of days from "topping to the maturity of the middle tobacco leaves" and the number of days from "topping to the over-maturity of the middle tobacco leaves", as well as derived indicators based on the number of days from "topping to the maturity of the middle tobacco leaves" and the number of days from "topping to the over-maturity of the middle tobacco leaves".

6. The method for predicting the over-ripe stage of the middle tobacco leaves of flue-cured tobacco according to claim 5, characterized in that: The derived indicators include: "topping - middle tobacco leaves over-mature" days - "topping - middle tobacco leaves mature" days, "topping - middle tobacco leaves mature" days + "topping - middle tobacco leaves over-mature" days, "topping - middle tobacco leaves over-mature" days / "topping - middle tobacco leaves mature" days, "topping - middle tobacco leaves mature" days × "topping - middle tobacco leaves over-mature" days, "topping - middle tobacco leaves mature" days × "topping - middle tobacco leaves mature" days, "topping - middle tobacco leaves over-mature" days × "topping - middle tobacco leaves over-mature" days.

7. The method for predicting the over-ripe stage of the middle tobacco leaves of flue-cured tobacco according to claim 1, characterized in that: The prediction model is: d2 = (d1 - 7.9236) / 0.6783 Among them, d2 is the number of days from "topping to over-ripening of the middle tobacco leaves", and d1 is the number of days from "topping to ripening of the middle tobacco leaves".

8. A system for predicting the over-ripe stage of middle tobacco leaves, characterized in that: For implementing the method for predicting the over-maturity period of the middle part of the flue-cured tobacco leaves according to any one of claims 1 to 7, the system comprises: a collection module, a prediction module; The acquisition module is used to obtain the dates of "topping" and "maturity of middle tobacco leaves" of the flue-cured tobacco to be predicted, and calculate the number of days from "topping to maturity of middle tobacco leaves"; The prediction module is used to input the number of days from "topping to middle tobacco leaves maturing" into a preset prediction model, output the number of days from "topping to middle tobacco leaves over-maturity" of the flue-cured tobacco to be predicted, and predict the date on which the middle tobacco leaves of the flue-cured tobacco to be predicted will reach an over-maturity state based on the number of days from "topping to middle tobacco leaves over-maturity"; wherein the prediction model is constructed based on the regularity of the time quantity between the number of days from "topping to middle tobacco leaves maturing" and the number of days from "topping to middle tobacco leaves over-maturity" of flue-cured tobacco.

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