METHOD FOR TAPPING YIELD POTENTIAL OF SACCHARUM OFFICINARUM BY CONTROLLING TIME OF PLASTIC MULCHING

Abstract

A method for tapping a yield potential of Saccharum officinarum by controlling a time of plastic mulching is provided. The method includes: (1) plastic mulching: mulching a Saccharum officinarum furrow in a Saccharum officinarum field fully with a wide plastic film in a direction parallel to the Saccharum officinarum furrow, and covering the plastic film directly above the Saccharum officinarum furrow with soil with a certain thickness along the Saccharum officinarum furrow, such that the plastic film is tightly attached to soil in the Saccharum officinarum furrow; (2) control of the time of plastic mulching, and (3) plastic film recycling treatment. The method of the present disclosure is advanced, practical, easy to operate, and easy to promote.

Claims

1. A method for tapping a yield potential of sugarcane by controlling a time of plastic mulching, comprising: a plastic mulching, a control of the time of plastic mulching, and a plastic film recycling treatment, and the method specifically comprising the following steps: (1) the plastic mulching: mulching a sugarcane furrow in a sugarcane field fully with a plastic film in a direction parallel to the sugarcane furrow, and covering the plastic film directly above the sugarcane furrow with a soil with a predetermined thickness along the sugarcane furrow, such that the plastic film is tightly attached to the soil in the sugarcane furrow; (2) the control of the time of plastic mulching: performing, based on two-year data comprising a complete degradation condition of the plastic film mulching a soil surface and a yield change pattern of the sugarcane, a logistic fitting on a yield impact according to a regression equation $y=\frac{k}{\left(1+{\mathrm{ae}}^{-\mathrm{bt}}\right)},$ and deriving a curve equation $y=\frac{1.55}{\left(1+3.5e^{-2.16t}\right)};$ accurately controlling the time of plastic mulching at three time points, namely $t_1=\frac{\left(\mathrm{In}a-1.317\right)}{b},t_2=\frac{\mathrm{In}a}{b},\mathrm{and}{t}_3=\frac{\left(\mathrm{In}a+1.317\right)}{b};$ deriving, through a 100-times descent iterative fitting, the three time points as endpoints, namely day 0, day 58, and day 119, wherein t.sub.1 is 3 through a formula calculation, but considering that the time of plastic mulching is a non-negative number, t.sub.1 is limited to 0, meaning that no plastic mulching is performed; in the 100-times descent iterative fitting, through an observation, there is no significant yield change after a time point defined by day 156; and therefore, the time of plastic mulching is divided into four mulching periods, namely a mulching period with a medium-to-low yield potential, defined by days 0-58, with a yield potential of 32.8-77.5 t/ha, a mulching period with a medium-to-high yield potential, defined by days 58-119, with a yield potential of 77.5-122.2 t/ha, a mulching period with a high yield potential, defined by days 119-156, with a yield potential of 122.2-138.8 t/ha, and an ineffective mulching period after day 156, with no significant yield increase; and (3) the plastic film recycling treatment: cleaning, by a plastic film recycling machine or a manual recycling method, the plastic film out of the sugarcane field, removing the soil on the plastic film, and sending a recycled plastic film to a plastic film recycling station for a centralized treatment.

2. The method for tapping the yield potential of the sugarcane by controlling the time of plastic mulching according to claim 1, wherein the plastic film is a fully biodegradable film, a weeding polyethylene film, or an ordinary polyethylene film.

3. The method for tapping the yield potential of the sugarcane by controlling the time of plastic mulching according to claim 1, wherein the plastic film has a width of 1.5-1.8 m and a thickness of 0.010-0.012 mm.

4. The method for tapping the yield potential of the sugarcane by controlling the time of plastic mulching according to claim 1, wherein the plastic film is intended for a fully mulching purpose, with an overlap of about 10 cm with an adjacent plastic film.

5. The method for tapping the yield potential of the sugarcane by controlling the time of plastic mulching according to claim 1, wherein the predetermined thickness of the soil covered is 3-4 cm.

6. The method for tapping the yield potential of the sugarcane by controlling the time of plastic mulching according to claim 1, wherein the time of plastic mulching is controlled at the three time points, namely day 0, day 58, and day 119, if the plastic film is a fully biodegradable film, the three time points refer to a degradation time of the fully biodegradable film; and if the plastic film is a weeding polyethylene film or an ordinary polyethylene film, the three time points refer to an uncovering time of the weeding polyethylene film or the ordinary polyethylene film.

7. A method for tapping a yield potential of sugarcane by controlling a time of plastic mulching, comprising: (1) performing, based on two-year data of a test site comprising a complete degradation condition of a plastic film covering a soil surface and a yield change pattern of a standard variety of the sugarcane, a logistic fitting on a yield impact according to a regression equation $y=\frac{k}{\left(1+{\mathrm{ae}}^{-\mathrm{bt}}\right)},$ and determining corresponding values of k, a, and h in the regression equation; (2) calculating, based on the corresponding values of k, a, and b, three time points, namely $t_1=\frac{\left(\mathrm{In}a-1.317\right)}{b},t_2=\frac{\mathrm{In}a}{b},\mathrm{and}{t}_3=\frac{\left(\mathrm{In}a+1.317\right)}{b};$ deriving, through a 100-times descent iterative fitting, mulching days corresponding to the three time points, namely T.sub.1, T.sub.2, and T.sub.3, wherein T.sub.1-T.sub.2 defines a mulching period with a medium-to-low yield potential; T.sub.2-T.sub.3 defines a mulching period with a medium-to-high yield potential; and T.sub.3- defines a mulching period with a high yield potential; and (3) substituting the mulching days T.sub.1, T.sub.2, and T.sub.3 into a curve equation of the 100-times descent iterative fitting to derive yield potentials corresponding to the mulching days, namely Y.sub.1, Y.sub.2, and Y.sub.3, wherein a yield potential defined by Y.sub.1-Y.sub.2 corresponds to the mulching period with the medium-to-low yield potential, a yield potential defined by Y.sub.2-Y.sub.3 corresponds to the mulching period with the medium-to-high yield potential, and a yield potential greater than Y.sub.3 corresponds to the mulching period with the high yield potential.

8. The method for tapping the yield potential of the sugarcane by controlling the time of plastic mulching according to claim 7, further comprising: selecting a mulching day T.sub.4 from a curve of the 100-times descent iterative fitting, wherein a daily yield increase after T.sub.4 is less than 5%; correcting the mulching period with the high yield potential to T.sub.3-T.sub.4 and an ineffective mulching period to T.sub.4-; and calculating a yield potential Y.sub.4 corresponding to the mulching day T.sub.4, and correcting the yield potential corresponding to the mulching period with the high yield potential to Y.sub.3-Y.sub.4.

9. The method for tapping the yield potential of the sugarcane by controlling the time of plastic mulching according to claim 8, wherein the mulching day T.sub.1 is non-negative; and if T.sub.1 is calculated as negative, T.sub.1 is taken as 0.

10. The method for tapping the yield potential of the sugarcane by controlling the time of plastic mulching according to claim 9, further comprising: correcting, if there is a temperature difference between a target planting site and the test site, the mulching days T.sub.1, T.sub.2, and T.sub.3 respectively through temperature correction coefficients .sub.1, .sub.2, and .sub.3, wherein after correction, T.sub.1=.sub.1T.sub.2, and .sub.1 denotes a ratio of an average temperature of a soil layer in the test site during the mulching period with the medium-to-low yield potential to an average temperature of a soil layer in the target planting site during the mulching period with the medium-to-low yield potential; T.sub.2=.sub.2T.sub.3, and .sub.2 denotes a ratio of an average temperature of the soil layer in the test site during the mulching period with the medium-to-high yield potential to an average temperature of the soil layer in the target planting site during the mulching period with the medium-to-high yield potential; and T.sub.3=.sub.3T.sub.4, and .sub.3 denotes a ratio of an average temperature of the soil layer in the test site during the mulching period with the high yield potential to an average temperature of the soil layer in the target planting site during the mulching period with the high yield potential.

11. The method for tapping the yield potential of the sugarcane by controlling the time of plastic mulching according to claim 10, further comprising: correcting, if there is a difference between an actual variety of the sugarcane planted and the standard variety of the sugarcane, the yield potential through a variety correction coefficient , wherein after correction, Y.sub.1=Y.sub.1, Y.sub.2=Y.sub.2, Y.sub.3=Y.sub.3, and Y.sub.4=Y.sub.4; and the variety correction coefficient is an empirical value trained and adjusted through an acquired learning.

12. The method for tapping the yield potential of the sugarcane by controlling the time of plastic mulching according to claim 11, wherein the plastic film is a fully biodegradable film, and the mulching day T of the plastic film lasts until a day when a 5-20 cm crack or break occurs in a surface of the plastic film.

13. The method for tapping the yield potential of the sugarcane by controlling the time of plastic mulching according to claim 11, wherein the plastic film is a weeding polyethylene film or an ordinary polyethylene film, and the mulching day T of the plastic film lasts until an uncovering time of the plastic film.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0039] To describe the technical solutions in the embodiments of the present disclosure more clearly, the drawings required for describing the embodiments are briefly described below. It should be understood that the following drawings show merely some embodiments of the present disclosure, and thus should not be regarded as a limitation to the scope. A person of ordinary skill in the art may still derive other related drawings from these drawings without creative efforts.

[0040] FIGURE is a fitting curve of a time of plastic mulching and a yield of sugarcane according to the present disclosure.

DETAILED DESCRIPTION OF THE EMBODIMENTS

[0041] To make the objective, technical solutions, and advantages of the examples of the present disclosure clearer, the technical solutions in the examples of the present disclosure will be described clearly and completely below. If no specific conditions are specified in the examples, the examples will be implemented under conventional conditions or the conditions recommended by the manufacturer. If the reagents or instruments used do not indicate the manufacturer, they are all conventional products that can be commercially available.

[0042] A method for tapping a yield potential of sugarcane by controlling a time of plastic mulching according to an embodiment of the present disclosure is specifically described below.

[0043] The features and properties of the present disclosure are further described in detail below in conjunction with examples.

Embodiment 1

[0044] The present disclosure provides a method for tapping a yield potential of sugarcane by controlling a time of plastic mulching. The method specifically includes the following steps:

[0045] (1) A test site is located at the Lengshuigou Base of the Sugarcane Research Institute of the Yunnan Academy of Agricultural Sciences (in Kaiyuan City, Yunnan Province, China), and a standard variety of sugarcane is Yunzhe 081609.

[0046] (2) Based on two-year data of a test site including a complete degradation condition of a plastic film covering a soil surface and a yield change pattern of a standard variety of sugarcane, logistic fitting is performed on a yield impact according to a regression equation

[00006]$y=\frac{k}{\left(1+{\mathrm{ae}}^{-\mathrm{bt}}\right)},$

and corresponding values of k, a, and b in the regression equation are determined, that is, k=1.55, a=3.5, and b=2.16. Therefore, through the fitting, a curve equation is derived, namely

[00007]$y=\frac{1.55}{\left(1+3.5e^{-2.16t}\right)}$

(shown in the FIGURE).

[0047] (3) Based on the corresponding values of k, a, and b, three time points, namely

[00008]$t_1=\frac{\left(\mathrm{In}a-1.317\right)}{b},t_2=\frac{\mathrm{In}a}{b},\mathrm{and}{t}_3=\frac{\left(\mathrm{In}a+1.317\right)}{b},$

are calculated. Through 100-times descent iterative fitting, three mulching days corresponding to the three time points are derived, namely T.sub.1=3, T.sub.2=58, and T.sub.3=119. T.sub.1 is taken as 0, and a mulching day T.sub.4=156 is selected from a curve of 100-times descent iterative fitting. Therefore, a mulching period with a medium-to-low yield potential is defined by days 0-58, a mulching period with a medium-to-high yield potential is defined by days 58-119, a mulching period with a high yield potential is defined by days 119-156, and an ineffective mulching period is defined by a period after day 156.

[0048] (4) The mulching days T.sub.1, T.sub.2, T.sub.3, and T.sub.4 are substituted into a curve equation of 100-times descent iterative fitting to derive yield potentials corresponding to the mulching days, namely Y.sub.1=32.8 t/ha, Y.sub.2=77.5 t/ha, Y.sub.3=122.2 t/ha, and Y.sub.4=138.8 t/ha. A yield potential corresponding to the mulching period with a medium-to-low yield potential is 32.8-77.5 t/ha, a yield potential corresponding to the mulching period with a medium-to-high yield potential is 77.5-122.2 t/ha, and a yield potential corresponding to the mulching period with a high yield potential is 122.2-138.8 t/ha.

[0049] (5) Based on the standard variety of sugarcane, some common varieties of sugarcane in Yunnan were tested using a single variable method. By comparing the yield differences derived with the single variable method, a variety correction coefficient of sugarcane is derived, as shown in Table 1.

TABLE-US-00001 TABLE 1 Variety Correction Coefficient of sugarcane Variety Yunzhe081609 Yunzhe0551 Yunzhe15505 Liucheng05-136 Yuetang93-159 / 1 0.98 0.88 0.98

[0050] It should be noted that the variety correction coefficient of sugarcane is generated based on the standard variety of sugarcane. If there is a change in the standard variety of sugarcane, the variety correction coefficient of sugarcane will change accordingly. The variety correction coefficient of sugarcane is an empirical value that can be continuously adjusted and optimized in actual production. For a sugarcane variety not shown in Table 1, the correction coefficient can also be assigned, adjusted, and optimized in the same way.

Application Example 1

[0051] This application example tests the method for tapping a yield potential of sugarcane by controlling a time of plastic mulching specifically according to the following steps.

[0052] (1) Variety selection. A high-quality sugarcane variety, Yunzhe 081609, was selected. In January, healthy seedlings of the high-quality sugarcane variety were planted at the Lengshuigou Base in Kaiyuan City, Honghe Prefecture, Yunnan Province.

[0053] (2) Plowing and furrowing. Deep plowing, deep loosening, and fine raking were carried out in a sugarcane field to finely break the soil. A sugarcane furrow was excavated along a contour line, with a depth of 40 cm, a bottom width of 25 cm, and a row spacing of 120 cm.

[0054] (3) Fertilization and pesticide application. 1,800 kg/ha of biological manure and 600 kg/ha of slow release fertilizer specially formulated for sugarcane were applied in the sugarcane furrow. For a sugarcane field with aphids and borers, 0.6 kg/ha of slow-release, low-toxicity, and efficient pesticide Fuge was mixed with fertilizer and applied to the sugarcane furrow for one time.

[0055] (4) Planting and soil covering. After the sugarcane furrow was excavated, the seedlings were planted in a timely manner, 10,000 seedlings per mu. After planting, the seedlings were mulched with about 10 cm of soil in a timely manner.

[0056] (5) Watering. After planting and soil covering, the seedlings were watered in a timely manner, with a watering amount of about 5 t.

[0057] (6) Mulching and soil covering. A fully biodegradable film with a width of 1.8 m, a thickness of 0.010 mm, and a degradation time of 100 days was used to mulch the sugarcane field in a direction parallel to the sugarcane furrow. The fully biodegradable film directly above the sugarcane furrow was mulched with 4 cm thick soil along the sugarcane furrow. The fully biodegradable film was overlapped for about 10 cm.

[0058] (7) Inter-tillage management. During the peak tillering period of sugarcane and after the degradation of the plastic film, inter-tillage, fertilization, and ridging were carried out in a timely manner. 1,200 kg/ha of slow-release fertilizer specifically formulated for sugarcane was applied. After fertilization, soil was ridged for a thickness of approximately 10 cm. During the elongation period of sugarcane, air tractors were flied for crop-dusting in a timely manner based on the pest condition.

[0059] (8) Harvesting. After the sugarcane matured, it was manually cut into the soil at a depth of 5 cm.

Application Examples 2 to 10

[0060] Application Examples 2 to 10 make minor adjustments based on Application Example 1, and the main differences are shown in Table 2.

TABLE-US-00002 TABLE 2 Planting Parameters of sugarcane Degradation Application Planting Film (uncovering) Example Variety time Location Film type thickness/mm time/day Application Yunzhe081609 January Lengshuigou, Kaiyuan City, Fully 0.01 100 Example 1 Honghe Prefecture, Yunnan biodegradable Province film Application Yunzhe0551 March Xiayun Village, Shangyun Polyethylene 0.01 119 Example 2 Town, Lancang County, film Puer City, Yunnan Province Application Yunzhe15505 March Baomu Village, Fengshan Fully 0.01 90 Example 3 Town, Jinggu County, Puer biodegradable City, Yunnan Province film Application Yunzhe081609 February Menghai County, Fully 0.01 120 Example 4 Xishuangbanna Prefecture, biodegradable Yunnan Province film Application Liucheng05136 March Yun County, Lincang City, Fully 0.012 75 Example 5 Yunnan Province biodegradable film Application Yuetang93159 March Nongba Village, Gengma Fully 0.01 90 Example 6 Town, Gengma County, biodegradable Lincang City, Yunnan film Province Application Yunzhe0551 December Mangguo Village, Gengma Polyethylene 0.01 130 Example 7 Town, Gengma County, film Lincang City, Yunnan Province Application Yunzhe081609 January Guichao Town Planting Polyethylene 0.01 120 Example 8 Region, Funing County, film Wenshan Prefecture, Yunnan Province Application Yunzhe081609 January Guichao Town Planting Polyethylene 0.01 50 Example 9 Region, Funing County, film Wenshan Prefecture, Yunnan Province Application Yunzhe081609 January Guichao Town Planting Polyethylene 0.01 160 Example 10 Region, Funing County, film Wenshan Prefecture, Yunnan Province

Test Example 1

[0061] Based on the function of Embodiment 1, the actual parameters of Application Examples 1 to 10 were corrected, and the correction results are shown in Table 3.

TABLE-US-00003 TABLE 3 Function Correction Results (T in days; and Y in t .Math. ha.sup.1) Application Example .sub.1 .sub.2 .sub.3 T.sub.2 T.sub.3 T.sub.4 Y.sub.1 Y.sub.2 Y.sub.3 Y.sub.4 Embodiment 1 1.00 1.00 1.00 58 119 156 1.00 32.8 77.5 122.2 138.8 Application Example 1 0.915 0.896 0.897 53 107 140 1.00 32.8 77.5 122.2 138.8 Application Example 2 0.798 0.821 0.868 46 98 135 1.00 32.8 77.5 122.2 138.8 Application Example 3 0.763 0.784 0.833 44 93 130 0.98 32.1 76.0 119.8 136.0 Application Example 4 0.946 0.924 0.956 55 110 149 1.00 32.8 77.5 122.2 138.8 Application Example 5 0.785 0.802 0.844 46 95 132 0.88 28.9 68.2 107.5 122.1 Application Example 6 0.804 0.825 0.868 47 98 135 0.98 32.1 76.0 119.8 136.0 Application Example 7 1.103 1.035 1.043 64 123 163 1.00 32.8 77.5 122.2 138.8 Application Example 8 0.935 0.927 0.910 54 110 142 1.00 32.8 77.5 122.2 138.8 Application Example 9 0.935 0.927 0.910 54 110 142 1.00 32.8 77.5 122.2 138.8 Application Example 10 0.935 0.927 0.910 54 110 142 1.00 32.8 77.5 122.2 138.8

[0062] The actual degradation (uncovering) times in Application Examples 1 to 10 were recorded, the mulching periods were determined according to Table 3, and the yield range was estimated. By comparing the estimated yield with the actual yield, the accuracy of the function was determined, with the results shown in Table 4.

TABLE-US-00004 TABLE 4 Function Accuracy Test Does it Actual comply Degradation Estimated yield with the Application (uncovering) yield/ Y/ corrected Example time/day Mulching period t .Math. ha.sup.1 t .Math. ha.sup.1 function Application 100 Mulching period with a 77.5-122.2 115.20 Yes Example 1 medium-to-high yield potential Application 119 Mulching period with a 122.2-138.8 128.70 Yes Example 2 high yield potential Application 90 Mulching period with a 76.0-119.8 108.90 Yes Example 3 medium-to-high yield potential Application 120 Mulching period with a 122.2-138.8 132.90 Yes Example 4 high yield potential Application 75 Mulching period with a 68.2-107.5 95.85 Yes Example 5 medium-to-high yield potential Application 90 Mulching period with a 76.0-119.8 107.85 Yes Example 6 medium-to-high yield potential Application 130 Mulching period with a 122.2-138.8 138.00 Yes Example 7 high yield potential Application 120 Mulching period with a 122.2-138.8 138.25 Yes Example 8 high yield potential Application 50 Mulching period with a 32.8-77.5 76.50 Yes Example 9 medium-to-low yield potential Application 160 Ineffective mulching 138.8 138.80 Yes Example 10 period

[0063] As shown in Table 4, the method of the present disclosure can accurately estimate the impact of different times of plastic mulching on the yield of sugarcane. The present disclosure takes three time points, namely T.sub.2, T.sub.3, and T.sub.4 as endpoints to divide the time of plastic mulching into four mulching periods, namely a mulching period with a medium-to-low yield potential, defined by 0-T.sub.2; a mulching period with a medium-to-high yield potential, defined by T.sub.2-T.sub.3 a mulching period with a high yield potential, defined by T.sub.3-T.sub.4; and an ineffective mulching period after T.sub.4, during which the yield of sugarcane is no longer significantly increased.

[0064] The present disclosure presents a local application example in Yunnan. The present disclosure takes three time points, namely day 58, day 119, and day 156, as endpoints to divide the time of plastic mulching into four mulching periods, namely a mulching period with a medium-to-low yield potential, defined by days 0-58, with a yield of 32.8-77.5 t/ha; a mulching period with a medium-to-high yield potential, defined by days 58-119, with a yield potential of 77.5-122.2 t/ha; a mulching period with a high yield potential, defined by days 119-156, with a yield potential of 122.2-138.8 t/ha; and an ineffective mulching period after day 156, during which the yield of sugarcane is no longer significantly increased.

[0065] The method of the present disclosure is not limited to the local application in Yunnan Province. When the method of the present disclosure is applied to other sugarcane varieties in other regions, further in-depth research is needed according to local conditions, so as to further optimize the variety correction coefficient of sugarcane and the yield potential range of different sugarcane varieties.

[0066] The above described are merely preferred embodiments of the present disclosure and is not intended to limit the present disclosure, and various changes and modifications of the present disclosure may be made by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and scope of the present disclosure should be included within the protection scope of the present disclosure.