A method for predicting the heading date of photosensitive three-line male-sterile japonica rice
By constructing a photosensitive three-line male-sterile rice heading date prediction model, and combining latitude and altitude to predict the rice heading date, the problem of inconsistent flowering dates between male and female parents was solved, thereby improving pollination effect and increasing rice yield.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- ZHEJIANG ACADEMY OF AGRICULTURE SCIENCES
- Filing Date
- 2023-09-22
- Publication Date
- 2026-07-17
AI Technical Summary
Current technology requires the male and female parents to have good flowering periods during the rice pollination stage. When there is a large difference in the heading time between the male and female parents, the pollination effect is poor, which affects the rice yield and delays the breeding process.
By recording and analyzing the sunshine duration during the plant's growing season, a model for predicting the heading date of photosensitive three-line male-sterile japonica rice was constructed. Combined with latitude and altitude, the rice heading date was predicted to guide timely sowing during planting, ensuring that the overlap time between the heading dates of the female and male parents is greater than 50%, thus guaranteeing pollination effectiveness.
It improved pollination efficiency during the pollination stage, increased rice yield, and accelerated the breeding process.
Smart Images
Figure CN117252010B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the technical field of rice cultivation, and in particular to a method for predicting the heading date of a photosensitive three-line male-sterile japonica rice. Background Technology
[0002] Rice is one of my country's most important food crops, and my country is a major rice producer and consumer. Hybrid indica-japonica rice not only has the fluffy aroma of indica rice but also the smooth, slightly sweet taste of japonica rice, and its yield is significantly higher.
[0003] Chinese patent CN1014298B discloses a method for producing interspecific hybrid rice of indica and japonica varieties, including chemical emasculation, safety isolation, timely sowing, reasonable planting, appropriate row ratio, regulating flowering period, artificial pollination, and measures for removing impurities and inferior varieties. Specifically, in the stage of regulating flowering period and artificial pollination: under favorable flowering conditions, one day before the male parent heads, spray "920 Power" 1-2 times at a rate of 3-4 grams per mu to raise the male parent's flower position by 15-20 cm; after the female parent heads, spray "920 Power" once more at a rate of 1 gram per mu. After spraying the female parent with "920 Power", cut off 1 / 3 of the female parent's canopy leaves. During full bloom, collect pollen for artificial pollination.
[0004] The existing technical solutions mentioned above have the following drawbacks: During the rice pollination stage, it is often necessary for the male and female parents to have good flowering periods. When the male and female parents have significantly different heading times, the pollination effect during the pollination stage cannot be guaranteed, which can easily have a significant impact on rice yield and delay the research process of rice breeding.
[0005] The inventors of this application selected the male parents Zhehui H818 and Zhehui F1015, which are late-maturing medium-grain indica rice varieties in various regions. Their growth period is mainly determined by the temperature during the growing season, and the heading date can be predicted relatively well based on the statistics of effective accumulated temperature. The inventors selected a photosensitive three-line male-sterile japonica rice as the female parent. The ecological planting area of photosensitive japonica rice is the entirety of Zhejiang Province and Shanghai Municipality in the middle and lower reaches of the Yangtze River, southern Jiangsu Province, the Yangtze River basin in Hubei Province and Anhui Province, and also high-altitude areas of the Yunnan-Guizhou Plateau. When producing indica-japonica hybrid rice of the Japonica-male-sterile / Indica-male-sterile combination in different locations in southern rice-growing areas, it is still necessary to more accurately predict the heading date of the photosensitive japonica rice male-sterile line, ensuring that the overlap time between the female and male parent heading dates is greater than 50% of the male parent's heading date, thereby guaranteeing the pollination effect during the pollination stage. Summary of the Invention
[0006] To address the shortcomings of existing technologies, the purpose of this invention is to provide a method for predicting the heading date of photosensitive three-line male-sterile japonica rice. By predicting the heading date of photosensitive three-line male-sterile japonica rice, the method guides timely sowing during planting, ensures that the overlap time between the heading dates of the female and male parents is greater than 50% of the heading date time of the male parent, and guarantees the pollination effect during the pollination stage.
[0007] The above-mentioned objective of this invention is achieved through the following technical solutions:
[0008] A method for predicting the heading date of a photosensitive three-line male-sterile japonica rice, characterized by the following steps: S1, recording and analyzing the changes in day length during the plant's growing season and plotting curves;
[0009] S2, based on the daily sunshine duration data of the region, the regression equation is fitted and obtained;
[0010] S3, taking Hangzhou as the benchmark, calculate the difference in latitude between each test point and Hangzhou and the difference in the number of days with the same sunshine duration, and the ratio of the two is the influence coefficient k of the local shortened days;
[0011] S4. Analyze the data and construct a model to predict the heading date of indica-japonica hybrid rice, using Hangzhou as a benchmark.
[0012] Shortened days: D = (Hangzhou latitude - test point latitude) × k + (test point altitude - 100) / 100 × k × i, where k is the influence coefficient;
[0013] i is the correction factor
[0014] When the altitude (m) of the test point ∈ [0, 200], i = 0.
[0015] When the altitude (m) of the test point ∈ (200, 400], i = 0.5.
[0016] When the altitude of the test point is greater than 400m, i = 1;
[0017] S5, Verify the model constructed in S4.
[0018] By adopting the above technical solution, based on the characteristics of photosensitive three-line male-sterile japonica rice, the sunshine duration during its growing season is recorded and analyzed. Based on the regression equation obtained from the daily sunshine duration data of the region, using Hangzhou as a benchmark, the latitude difference between each experimental site and Hangzhou, as well as the difference in the number of days with the same sunshine duration between each experimental site and Hangzhou, are calculated. The ratio obtained by dividing the two is the influence coefficient k of the local shortened days. By fully utilizing the characteristics of the photosensitive three-line male-sterile japonica rice, the influence coefficient k is made more accurate. A prediction model for the heading period of the photosensitive three-line male-sterile japonica rice is constructed, combining latitude and altitude to predict the heading period of the rice. This guides timely sowing, ensuring that the heading times of the female and male parents are similar, and that the overlap time between the heading periods of the female and male parents is greater than 50% of the male parent's heading period, ensuring good pollination during the pollination stage. This, to a certain extent, increases rice yield and accelerates the research process of rice breeding.
[0019] Preferably, in step S3, when the latitude of the test point ∈ (27N °, 34N °), the value of k is 3.7; when the latitude of the test point ∈ (26.9N °, 18N °), the value of k is 2.16.
[0020] By adopting the above technical solution, the influence coefficient k can be further determined based on the latitude of the test point, which has a good guiding effect and can further increase the yield of rice to a certain extent.
[0021] Preferably, in S1 and S5, Zhe04A is selected as the rice material for planting.
[0022] By adopting the above technical solution and selecting Zhe04A, a high-quality rice material that is disease-resistant, early-flowering, has a high cross-pollination rate, compact plant type, strong combining ability, and good late-stage maturity, the obtained model is more accurate.
[0023] Preferably, in step S5, Zhejiang 04A seedlings are planted in different areas. After sowing at the same time, the seedlings are transplanted to the field after growing for 25 days. Each Zhejiang 04A seedling is planted in three plots in the corresponding area, with 240 seedlings in each plot, to conduct parallel trials and implement unified management.
[0024] By adopting the above technical solution, Zhejiang 04A can be planted in different areas at the same time and managed in a unified manner, resulting in a more accurate model.
[0025] Preferably, the suitable ambient temperature for planting the Zhejiang 04A variety is 22–38℃.
[0026] By adopting the above technical solution, the rice growth conditions are suitable under this ambient temperature, and the resulting model is relatively accurate, avoiding errors caused by extreme temperatures to a certain extent.
[0027] Preferably, nitrogen fertilizer is applied when planting the Zhe04A rice, and nitrogen fertilizer is also applied in a timely manner during the rice growth period.
[0028] By adopting the above technical solutions, appropriate nitrogen fertilizer is maintained during the rice growth process, which is suitable for rice growth and thus ensures the accuracy of the model to a certain extent.
[0029] Preferably, the model constructed in S4 is applicable to a latitude range of 18N°~34N°.
[0030] By adopting the above technical solution, this model has good accuracy in the range of 18°N to 34°N, and rice cultivation is a widespread agricultural activity in this latitude range.
[0031] Preferably, when validating the model in S5, field planting or artificial climate chamber planting is used for verification.
[0032] By adopting the above technical solutions, the model can be verified either through field planting or by simulating the local climate in an artificial climate chamber, which can save manpower and time costs to a certain extent.
[0033] In summary, the present invention has the following beneficial technical effects:
[0034] 1. Construct a predictive model for the heading date of a photosensitive three-line male-sterile japonica rice, and combine latitude and altitude to predict the heading date of this rice.
[0035] During the heading stage, the timing of planting is guided to ensure that the heading time of the female and male parents is similar, thus guaranteeing a good pollination effect during the pollination stage, which to some extent increases the yield of rice and accelerates the research process of rice breeding.
[0036] 2. Further determining the influence coefficient k based on the latitude of the test points has a good guiding effect and can further increase rice yield to a certain extent. Attached Figure Description
[0037] Figure 1 The duration of daylight in different regions recorded in this application is the duration of daylight in the growing season (May to November). Detailed Implementation
[0038] The present invention will now be described in further detail.
[0039] In this application, Zhe04A was used as the rice material in the experiment. Zhe04A is a BT-type late-season japonica rice three-line sterile line bred by the Institute of Crop and Nuclear Technology Utilization of Zhejiang Academy of Agricultural Sciences. Its main characteristics are high quality, disease resistance, early flowering, high cross-pollination rate, compact plant type, strong combining ability, and good late-stage maturity, resulting in a relatively accurate model. The hybrid combinations bred with Zhe04A generally have the following characteristics: moderate growth period, obvious heterosis, high yield potential, thick stems and lodging resistance, high quality and disease resistance, large panicles and many grains, good late-stage color change, and green stems with yellow maturity.
[0040] S1, record and analyze the changes in day length during the plant's growing season and plot the curves:
[0041] To analyze the differences in the heading period of rice plants from various regions (heading period of rice is defined as when 50% of the plants in a population have emerged 1-2 cm from the flag leaf; the date of heading is recorded, and the number of days between sowing and heading is calculated), the inventors meticulously recorded and analyzed the changes in photoperiod (i.e., sunshine duration) from May to November during the growing season. This involved investigating the sunrise and sunset times at the experimental site and calculating the daily sunshine duration from sowing to maturity, and then plotting the curves (see [link]). Figure 1The photoperiod variation curves show that the length of sunshine in various regions first increases, reaching its maximum in late June, and then decreases until November. Specifically, Jianhu County in Jiangsu Province reaches its maximum length of sunshine on June 25th, Fengxian District in Shanghai reaches its maximum sunshine duration on June 21st, and the remaining areas all reach their maximum sunshine duration on June 21st. As the latitude decreases from south to north by 33.45°N to 23.75°N (from Jianhu County in Jiangsu Province to Baise City in Guangxi Zhuang Autonomous Region), the maximum sunshine duration also decreases, from 14.37 hours to 13.60 hours.
[0042] S2, based on the daily sunshine duration data of the region, yields the regression equation:
[0043] Based on the daily sunshine duration data for each region, a scatter plot was drawn, and SPSS was used to fit the curve to obtain the regression equation. The formulas for calculating sunshine duration for each region are listed in Table 1. y represents the sunshine duration value, and x represents the date, with May 1st as x=0 and so on.
[0044] Table 1 Formula for sunshine duration at the experimental site
[0045] Table 3.1Experimental sunshine duration formula
[0046]
[0047] Note a: L1 = Qingfeng Town, Jianhu County, Jiangsu Province; L2 = Xinghui Farm, Fengxian District, Shanghai; L3 = Shuanglin Town, Nanxun District, Huzhou City, Zhejiang Province; L4 = Xucun Town, Haining City, Zhejiang Province; L5 = Experimental Farm of Zhejiang Academy of Agricultural Sciences, Hangzhou City, Zhejiang Province; L6 = Qiantan Town, Jiande City, Hangzhou City, Zhejiang Province; L7 = Huzhen Town, Longyou County, Quzhou City, Zhejiang Province; L8 = Laodaohe Subdistrict, Kaifu District, Changsha City, Hunan Province; L9 = Paishang Town, Xiangdong District, Pingxiang City, Jiangxi Province; L10 = Jinshi Town, Xinning County, Hunan Province; L11 = Lixin Town, Jianning County, Fujian Province; L12 = Tianzhou Town, Tianyang District, Baise City, Guangxi Zhuang Autonomous Region.
[0048] S3, taking Hangzhou as the benchmark, calculate the difference in latitude between each test point and Hangzhou and the difference in the number of days with the same sunshine duration, and the ratio of the two is the influence coefficient k of the local shortened days;
[0049] Based on the sunshine duration formulas for various regions, sunshine duration values y of 13.87, 13.50, and 13.17 were selected, and the dates corresponding to the x values were calculated. Taking Hangzhou as the benchmark, the difference in latitude between each test point and Hangzhou and the difference in the number of days with the same sunshine duration value were calculated, and the ratio of the two was the influence coefficient k of the local shortened days (Table 2).
[0050] Table 2 Influence coefficients of the heading stage prediction model
[0051]
[0052] Note a: Locations L1 to L12 are the same as Table 1;
[0053] Note b: y is the sunshine duration value of the test point, Xi is the difference in the number of days between the test point and the benchmark point Hangzhou for the same sunshine duration value, Li is the latitude difference between the test point and the benchmark point Hangzhou, and Xi / Li is the influence coefficient k.
[0054] S4. Analyze the data and construct a model to predict the heading date of indica-japonica hybrid rice, using Hangzhou as a benchmark, to shorten the time by several days:
[0055] D = (Latitude of Hangzhou - Latitude of test point) × k + (Elevation of test point - 100) / 100 × k × i, where k is the influence coefficient;
[0056] i is the correction factor
[0057] When the altitude (m) of the test point ∈ [0, 200], i = 0.
[0058] When the altitude (m) of the test point ∈ (200, 400], i = 0.5; when the altitude of the test point is greater than 400m, i = 1.
[0059] When the latitude of the test point ∈ (27N °, 34N °), the average values of the ratios (i.e., the influence coefficients) when y = 13.87 and y = 13.50 are 4.60 and 2.68 respectively, and the total average value of the two is 3.64; that is, Formula 1: Shortened days: D = (Latitude of Hangzhou - Latitude of test point) × 3.7 + (Altitude of test point - 100) / 100 × 3.7 × i.
[0060] When the latitude of the test point ∈ (26.9N °, 18N °), the average values of the ratios (i.e., the influence coefficients) when y = 13.50 and y = 13.17 are 2.68 and 1.64 respectively, and the total average value of the two is 2.16; that is, Formula 2: Shortened days: D = (Latitude of Hangzhou - Latitude of test point) × 2.16 + (Altitude of test point - 100) / 100 × 2.16 × i.
[0061] S5, verify the model formula 1 (Table 3) and formula 2 (Table 4) constructed in S4.
[0062] Conduct field trials
[0063] Field trials were conducted in multiple locations. Sowing and planting took place on May 28, 2022, in 12 different regions: Zhejiang Academy of Agricultural Sciences Experimental Farm in Hangzhou, Zhejiang Province; Shuanglin Town, Nanxun District, Huzhou City, Zhejiang Province; Huzhen Town, Longyou County, Quzhou City, Zhejiang Province; Xinning County, Hunan Province; Lixin Town, Jianning County, Fujian Province; Qingfeng Town, Jianhu County, Jiangsu Province; Xinghui Farm, Fengxian District, Shanghai; Xucun Town, Haining City, Zhejiang Province; Qiantan Town, Jiande City, Hangzhou City, Zhejiang Province; Laodaohe Street, Kaifu District, Changsha City, Hunan Province; Paishang Town, Xiangdong District, Pingxiang City, Jiangxi Province; and Tianyang County, Baise City, Guangxi Zhuang Autonomous Region. The experimental material, Zhe04A, was planted at these locations at the same time. After 25 days of growth, the seedlings were transplanted to the field. Zhe04A was planted in three plots within each region, with 240 plants in each plot, conducting parallel trials. The growth period of the materials was within the suitable environmental temperature range of 22-38℃. The field management methods were consistent across all experimental sites. Water and fertilizer management were carried out at the appropriate time, nitrogen fertilizer was applied at planting, and nitrogen fertilizer was applied in a timely manner during the rice growth period. Pest and disease control were also carried out.
[0064] Planting verification can also be carried out by simulating corresponding climate conditions in artificial climate chambers.
[0065] Table 3. Validation data for model formula 1 predicting heading date.
[0066]
[0067] Note a: *The number of days shortened is taken as an integer.
[0068] Note b: Location L1_L9 is the same as Table 1
[0069] Note c: K takes the value 3.7
[0070] Table 4. Validation data for Model Formula 2 predicting heading date.
[0071]
[0072] Note a: *The number of days shortened is rounded down.
[0073] Note b: Locations L10-L12 are the same as in the table above.
[0074] Note c: K takes the value 2.16
[0075] The data above shows that the heading date model has a certain guiding role in predicting heading. For regions with latitudes of 27-33°N, the predicted heading date is basically consistent with the actual heading date. For regions with latitudes of 23-26.5°N, the predicted heading date largely overlaps with the actual heading date, indicating that the prediction model has a certain degree of accuracy and feasibility. The predicted date can also provide some guidance based on the corresponding latitude and altitude, playing a role in timely sowing during planting. This ensures that the heading time of the female and male parents is similar, guaranteeing good pollination during the pollination stage. It also facilitates the implementation of corresponding remedial measures based on actual farmland conditions, thereby increasing rice yield to a certain extent and accelerating the research process of rice breeding.
[0076] This specific embodiment is merely an explanation of this application and is not intended to limit it. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they fall within the scope of the claims of this application.
Claims
1. A method for predicting the heading date of a photosensitive three-line male-sterile japonica rice, characterized in that: Includes the following steps: S1, record and analyze the changes in day length during the plant's growing season and plot the curves; S2, based on the daily sunshine duration data of the region, the regression equation is fitted and obtained; S3, taking Hangzhou as the benchmark, calculate the difference in latitude between each test point and Hangzhou and the difference in the number of days with the same sunshine duration, and the ratio of the two is the influence coefficient k of the local shortened days; S4. Analyze the data and construct a model to predict the heading date of indica-japonica hybrid rice, using Hangzhou as a benchmark. Shortened days: D = (Latitude of Hangzhou - Latitude of test point) × k + (Elevation of test point - 100) / 100 × k × i, Where k is the influence coefficient; i is the correction factor When the altitude (m) of the test point ∈ [0, 200], i = 0. When the altitude (m) of the test point ∈ (200, 400], i = 0.
5. When the altitude of the test point is greater than 400m, i=1; S5, Verify the model constructed in S4.
2. The method for predicting the heading date of a photosensitive three-line male-sterile japonica rice according to claim 1, characterized in that: In S3, when the latitude of the test point is (27N°, 34N°), the value of k is 3.7; when the latitude of the test point is (26.9N°, 18N°), the value of k is 2.
16.
3. The method for predicting the heading date of a photosensitive three-line male-sterile japonica rice according to claim 1, characterized in that: In S1 and S5, Zhe04A rice was selected as the rice material for planting.
4. The method for predicting the heading date of a photosensitive three-line male-sterile japonica rice according to claim 3, characterized in that: In step S5, Zhejiang 04A seedlings are planted in different areas. After sowing at the same time, the seedlings are transplanted to the field after growing for 25 days. Zhejiang 04A seedlings are planted in three plots in the corresponding areas, with 240 seedlings in each plot, to carry out parallel trials and uniform management.
5. The method for predicting the heading date of a photosensitive three-line male-sterile japonica rice according to claim 4, characterized in that: The suitable ambient temperature for planting the Zhejiang 04A variety is 22~38℃.
6. The method for predicting the heading date of a photosensitive three-line male-sterile japonica rice according to claim 4, characterized in that: When planting the Zhe04A variety, nitrogen fertilizer should be applied, and nitrogen fertilizer should be applied in a timely manner during the rice growth period.
7. The method for predicting the heading date of a photosensitive three-line male-sterile japonica rice according to claim 1, characterized in that: The model built in S4 is applicable to a latitude range of 18 N° to 34 N°.
8. The method for predicting the heading date of a photosensitive three-line male-sterile japonica rice according to claim 1, characterized in that: When validating the model in S5, field planting or artificial climate chamber planting is used for verification.