Cultivation method of wheat sown by interplanting under high temperature and symbiotic with previous crop for more than 30 days

Abstract

The present invention discloses a cultivation method for wheat under high temperature with interplanting and symbiosis with the previous crop for more than 30 days, and the steps include: (1) Selecting suitable varieties for planting, (2) Seed treatment, (3) Timely interplanting, (4) Reducing the seeding rate and seedlings, (5) Light rolling to reduce injury, (6) Early promotion for strong growth, etc. The inventor found that when growing in a shaded environment with too high temperature and lack of soil fertility, and the number of single-plant green leaves is always less than 4, the main stem leaf age of semi-winter wheat reaches 15 leaves and no ear differentiation will start, and it can be transformed into strong seedlings before winter when transferred to the open environment 10 - 20 days after the upper limit of the suitable sowing period. The present invention aims at the seasonal contradiction, stubble contradiction in multi-cropping areas and the deficiencies of the existing interplanting cultivation technology, advances the wheat interplanting date to 20 - 40 days before the upper limit of the suitable sowing period, and cooperates with measures such as suitable varieties, light rolling to reduce injury, early promotion for strong growth, etc., eliminates the side effects of a long symbiotic period and heavy rolling injury resulting in a slow seedling stage of 10 - 20 days, ensures the safety of wheat growth and development, and can also achieve cost reduction, yield increase and efficiency improvement.

Description

Technical Field

[0001] The present invention relates to the technical field of agricultural cultivation, and particularly to a cultivation method for wheat sown in relay under high temperature and symbiotic with the previous crop for more than 30 days. Background Art

[0002] Existing common knowledge about the stage development of wheat: The total number of main stem leaves of semi-winter wheat is 12 - 14, with a maximum of 14.0. After the wheat seedlings are induced by low temperature of 0 - 7.0 °C, when the main stem leaf age reaches 4.5 - 6.5 leaves, it enters the elongation stage of the growth cone (i.e., starts young spike differentiation), and then goes through 7.5 leaf age periods to enter the booting stage. Among them, from the beginning of wintering to the fully unfolded flag leaf, it takes about 6.0 - 7.0 leaf age periods. The emergence process of the fourth leaf from the top is synchronous with the differentiation period of glume primordium and the biological jointing stage, and the emergence process of the third leaf from the top is synchronous with the differentiation period of stamens and pistils and the phenological jointing stage. Therefore, one of the indicators for strong seedlings of semi-winter wheat before winter is: the main stem leaf age is 6.0 - 7.0 leaves, and the accumulated temperature before winter is 540 °C - 680 °C (about 110 °C - 120 °C is required from sowing to emergence, and about 70 °C - 80 °C is required for each leaf growth before winter). Long-term large-area production practice has confirmed that sowing too early (main stem leaf age ≥ 8.0 before winter, accumulated temperature before winter ≥ 760 °C) will surely cause premature start of young spike differentiation and premature jointing in spring, resulting in a significant decline in cold resistance in winter and early spring, serious freezing damage or a large number of dead seedlings, and a significant reduction in yield; sowing too late (main stem leaf age ≤ 4.0 before winter, accumulated temperature before winter ≤ 400 °C) is difficult to cultivate strong seedlings before winter, the jointing in spring is relatively late, and the dates of heading and maturity are also significantly postponed.

[0003] Relay-sown wheat is a special wheat cropping method in multi-cropping areas with tight light and heat resources. In order to fully tap the potential of resource utilization, wheat seeds are sown in the field during the late growth stage of the previous crop until harvest. Compared with single-cropped wheat, its advantages are: (1) It can seize early sowing in the late stubble, avoiding excessive late sowing of wheat and ensuring wheat yield and the annual total yield; (2) It has strong disaster resistance and avoidance ability against continuous rain during autumn harvest and autumn sowing; (3) It avoids the autumn rush, simplifies the autumn sowing operation, saves labor, and meets the current actual needs of many large-scale management entities.

[0004] In multi-cropping areas with tight light and heat resources, relay-sown wheat is common and widely used. The previous crops are diverse, including rice, autumn corn, cotton... However, in the existing technology, the relay-sowing date of wheat is only 7 - 15 days or even just 0 - 3 days from the harvest date of the previous crop, generally after the upper limit of the suitable sowing period for wheat. Currently, due to the long-term bias in wheat planting experience, the relay-sowing technology emphasizes that wheat cannot be sown too early. The two main reasons are: First, when the main stem leaf age before winter ≥ 8.0 leaves, it will cause premature jointing in spring and serious freezing damage or a large number of dead seedlings. Second, an increase in the symbiotic period will lead to a significant extension of the slow seedling stage of relay-sown wheat and a substantial increase in the difficulty of cultivating strong seedlings before winter.

[0005] In summary, aiming at the seasonal and crop rotation contradictions among multiple cropping systems and the deficiencies of the existing wheat relay cropping cultivation technology, breaking through the existing consensus on the stage development of wheat, innovating and developing the wheat relay cropping cultivation technology, cultivating winter pre-strong seedlings and the same single-plant ear-bearing ability as the single-cropped wheat sown at the appropriate time, and then steadily increasing the yield of relay cropped wheat and the annual yield. Therefore, it is of great significance to improve the competitiveness of wheat relay cropping cultivation technology, expand the area of relay cropped wheat, and ensure China's food security under the new situation. Summary of the Invention

[0006] The technical problem to be solved by the present invention: Aiming at the deficiencies of the existing wheat relay cropping cultivation technology, breaking through the existing consensus on the stage development of wheat, innovating and developing the wheat relay cropping cultivation technology, and proposing a cultivation method for wheat relay cropping at high temperature and symbiotic with the previous crop for more than 30 days, so that the wheat relay cropping cultivation technology has better adaptability to large-scale and full-process mechanized crop production, and further ensuring the yield of relay cropped wheat, the annual yield and the net benefit.

[0007] The present invention is realized through the following technical solutions:

[0008] A cultivation method for wheat relay cropping at high temperature and symbiotic with the previous crop for more than 30 days, including:

[0009] (1) Select suitable varieties: Select semi-winter late-maturing varieties suitable for local planting, and spring and weak spring varieties are prohibited;

[0010] (2) Seed treatment: Select a suitable seed dressing agent for seed dressing to prevent pest and disease damage and other biological hazards during the symbiotic period;

[0011] (3) Timely relay cropping: The upper limit of the suitable sowing period for wheat is October 10th. Sow wheat seeds into the field 20 - 40 days before the upper limit of the suitable sowing period for wheat, that is, from September 1st to September 20th; when the previous crop is rice, the paddy field relay cropping requires the surface of the paddy field to be wet but without waterlogging. When the previous crop is dryland crops such as autumn corn and cotton, the dryland relay cropping must sow wheat seeds into the topsoil; the population size of the previous crop must be moderate. When the population is too large to the extent that it is airtight and the ground cannot be seen from above, or when the population is too small to the extent that the ground between rows more than 1m away can be seen with the naked eye along the row direction, relay cropping cannot be carried out;

[0012] (4) Reduce the seeding rate and seedlings: Determine the wheat seeding rate of 5.0 - 17.5 kg / 667m 2 ;

[0013] (5)Light pressure damage reduction: Harvest the previous crop from October 20th to October 30th, which is 10 to 20 days after the upper limit of the suitable sowing period, and try to reduce the damage to the wheat seedlings during harvesting; all the straw must be transported out of the field within 4 days after harvesting.

[0014] (6)Early promotion and strong growth: Apply appropriate amounts of high-quality organic fertilizer, compound fertilizer and micronutrient fertilizer within 5 days after harvesting the previous crop.

[0015] For further improvement, in step (4), when the harvesting date is earlier, the estimated damage to the wheat seedlings by rolling is lighter, there is irrigation condition in the wheat season, and the co-growing period is long, the sowing rate of wheat takes a low value; when the harvesting date is late, the estimated damage to the wheat seedlings by rolling is heavier, there is no irrigation condition in the wheat season, and the co-growing period is short, the sowing rate of wheat takes a high value.

[0016] For further improvement, in step (4), the paddy field adopts drone seeding, and when the drone is seeding, it must fly more than 3 m above the rice canopy.

[0017] Now for further improvement, in step (5), it is prohibited to use large machinery to enter the field to pick up and bale straw.

[0018] Data from the special experiments conducted by the inventor team in Huai'an City from 2019 to 2020: For the semi-winter wheat variety Huaimai 33 sown on June 9, August 3, and September 8, 2019, when grown in a shaded environment with high temperatures and infertile soil (average daily temperature ≥ 20 °C, maximum daytime light intensity ≤ 2500 lux, unfertilized soil and no top dressing throughout the growth period), and with the number of green leaves per plant remaining below 4, by October 26 (16 days after the upper limit of the suitable sowing period for wheat in Huai'an City) when the wheat seedlings were transferred to the open field, the main stem leaf ages of the wheat seedlings reached 16.9 leaves and 8.9 leaves respectively; by November 10, the main stem leaf ages reached 18.3 leaves and 10.5 leaves respectively; by December 29, the main stem leaf ages reached 20.3 leaves and 13.8 leaves respectively; by January 18, the main stem leaf ages reached 21.1 leaves and 14.6 leaves respectively; by April 8, the wheat seedlings of both sowing dates entered the booting stage, and the total number of main stem leaves was 27 leaves and 21 leaves respectively. The maturity dates were both June 6, 2020, and the number of ears per plant was 29 ears and 39 ears respectively, and the number of filled grains in the main stem ears was 85 grains. The above special experiments showed that when grown in a shaded environment with high temperatures and infertile soil and with the number of green leaves per plant always less than 4, the semi-winter wheat would not start young spike differentiation even when the main stem leaf age reached 15 leaves, nor would it show premature jointing in spring. If transferred to the open field 10 - 20 days after the upper limit of the suitable sowing period, it could be transformed into strong seedlings before winter. This was because the total number of main stem leaves of semi-winter wheat would increase significantly compared to that of single-cropped wheat sown at the appropriate time. After being transferred to the open field, it would take another 10.1 and 12.1 leaf age periods to enter the booting stage, that is, it would take another 2.6 and 4.6 leaf age periods to enter the growth cone elongation stage (i.e., start young spike differentiation). However, if the maximum daytime light intensity during the shading period of the wheat seedlings was increased to above 6000 lux, or the soil was fertilized, or balanced top dressing was applied to keep the number of green leaves per plant at 6 or more, the semi-winter wheat would surely head in August - September before being transferred to the open field, and the total number of main stem leaves was generally only 15 - 16 leaves.

[0019] Principle of the present invention: By utilizing the above research results of the inventor, the sowing date of semi-winter wheat is advanced to 20 - 40 days before the upper limit of the suitable sowing period (i.e., sowing from September 1st to 20th in Huai'an City, and the upper limit date of the suitable sowing period for wheat in Huai'an City is approximately October 10th). Although the co-growing period is significantly increased and the leaf age of wheat at the time of the previous crop harvest (October 20th - 30th in Huai'an City) is increased, when entering the booting stage, the total number of main stem leaves finally increases by 2 - 5 leaves and reaches 15 - 18 leaves. Since the number of green leaves per plant has been kept below 4 before the previous crop harvest, after transferring to the open-field environment, it generally still needs to go through a seedling-slowing period and 2 - 3 leaf age periods, and will enter the growth cone elongation stage (i.e., the beginning of young spike differentiation, generally in the first and second ten days of December) when the main stem leaf age reaches 7.5 - 10.5 leaves. Therefore, the start date of its young spike differentiation is not earlier than that of the single-cropped wheat sown at the appropriate time. At the time of the previous crop harvest in the present invention, the main stem leaf age of semi-winter wheat is already 5 - 8 leaves, 5 seminal roots have already deeply penetrated into the soil, and even some secondary roots have penetrated into the soil. Even when encountering autumn drought, continuous autumn and winter drought and being unable to irrigate after harvesting the previous crop, the inhibitory effect is much smaller than that of traditional relay-sown wheat (at most 2 leaves and 1 heart, shallow seminal roots or even not yet in the soil). The increase of 2 - 5 in the total number of main stem leaves means an increase of 2 - 5 in the effective tillering nodes, and the potential for effective tillering is huge. Coupled with measures such as suitable varieties, reducing seeding rate and seedlings, reducing the degree of seedling rolling damage, and early application of fertilizers to promote weak seedlings, the side effects of a 10 - 20-day seedling-slowing period caused by a long co-growing period and heavy rolling damage are eliminated, and it is easy to obtain strong winter seedlings, the same number of ears per plant, and the same high actual yield as the single-cropped wheat sown at the appropriate time, ensuring the safety of wheat growth and development while achieving cost reduction, yield increase, and efficiency improvement.

[0020] Compared with the existing wheat relay-sowing cultivation technology, the present invention has the following two obvious advantages:

[0021] 1. The seedlings are strong before winter in the present invention. By utilizing the new results of the inventor, the sowing date of wheat is advanced to 20 - 40 days before the upper limit of the suitable sowing period. The wheat seedlings grow in a shaded environment with high temperature and lack of soil fertilizer. At the time of the previous crop harvest, the main stem leaf age is already 5 - 8 leaves, and the seminal roots have already deeply penetrated into the soil, and even secondary roots have penetrated into the soil. Even when encountering autumn drought, continuous autumn and winter drought and being unable to irrigate, the inhibitory effect is much smaller than that of traditional relay-sown wheat (at most 2 leaves and 1 heart, shallow seminal roots or even not yet in the soil). At the same time, with measures such as suitable varieties, reducing seeding rate and seedlings, reducing pressure and damage, and early application of fertilizers to promote weak seedlings, the side effects of a 10 - 20-day seedling-slowing period caused by a long co-growing period and heavy rolling damage are eliminated, and it is possible to obtain strong winter seedlings like those of the single-cropped wheat sown at the appropriate time, without causing premature young spike differentiation or premature spring jointing, and improving the cold resistance of the seedlings in winter and early spring.

[0022] 2. The present invention has strong applicability. The wheat plants in the present invention have the potential to produce 2 to 3 more effective tillers at the same time because the total number of leaves on the main stem and the effective tillering nodes are generally 2 to 5 more than those of suitable sowing wheat. Therefore, the present invention can easily obtain a more ideal number of ears and actual yield. Therefore, the present invention makes inter-seeding wheat more competitive in terms of cost saving, yield increase, and efficiency improvement compared with single-crop wheat sown at the right time, adapts to the current farming needs of inter-seeding wheat by new business entities, expands the area of ​​inter-seeding wheat, and steadily increases the yield of inter-seeding wheat and the annual yield. DETAILED DESCRIPTION

[0023] The upper limit of the suitable sowing period for wheat in Huai'an City is approximately October 10 (annual temperature 17.5°C, annual accumulated temperature before winter 665°C), 20 to 40 days before the upper limit of the suitable sowing period for wheat in Huai'an City, that is, September 20 (annual temperature 20.8°C, annual accumulated temperature before winter 1052°C) to September 1 (annual temperature 24.5°C, annual accumulated temperature before winter 1507°C), 10 to 20 days after the upper limit of the suitable sowing period for wheat in Huai'an City, that is, October 20 (annual temperature 14.4°C, annual accumulated temperature before winter 501°C) to October 30 (annual temperature 13.0°C, annual accumulated temperature before winter 360°C). The inventor established the experimental demonstration fields of the present invention at three locations in Huai'an City from 2019 to 2022. The specific cultivation technology scheme is as follows:

[0024] 1. Select suitable varieties: Select suitable late-maturing varieties of semi-winter plants through local special experiments, especially those with good cold resistance and high yield, such as Huaimai 33 and Huaimai 46. It is forbidden to use spring wheat varieties or weak spring wheat varieties;

[0025] 2. Seed treatment: Choose appropriate seed dressing agent to mix with seeds to prevent pests and diseases and other biological damage during the symbiotic period; when the previous crop is rice, the agent is mainly used to prevent damage from sheath blight, gray leafhoppers, and field snails; when the previous crop is dryland crops such as autumn corn and cotton, the agent should not only be able to prevent damage from sheath blight, gray leafhoppers, and field snails, but also be able to prevent damage from mole crickets, field mice, birds, etc.;

[0026] 3. Timely interplanting: interplant wheat seeds into the previous crop field from September 1 to 20; when interplanting wheat in rice fields, the surface must be moist but without water accumulation. Interplanting is not allowed when the surface is dry or there is water accumulation in some areas. When interplanting in dry fields, wheat seeds must be sown into the topsoil and cannot be directly sown on the soil surface; the size of the previous crop group must be moderate. When the group is too large and dense to the point where the ground is completely invisible when looking down, or when the group is too small to the point where the ground between rows 1m away can be seen with the naked eye along the row direction, interplanting is also not allowed;

[0027] 4. Reducing the variety and seeding rate: Determine the seeding rate based on factors such as the harvest date of the previous crop, the estimated degree of damage to the wheat seedlings by rolling, the length of the co - growth period, and the irrigation conditions in the wheat season. Generally, it is 5.0 - 17.5 kg / 667m 2 , when the harvest date is earlier, the estimated damage to the wheat seedlings by rolling is lighter, there is irrigation condition in the wheat season, and the co - growth period is long, take a lower value for the wheat seeding rate; when the harvest date is late, the estimated damage to the wheat seedlings by rolling is heavier, there is no irrigation condition in the wheat season, and the co - growth period is short, take a higher value for the wheat seeding rate; for paddy fields, drone seeding can be adopted, and when operating the drone for seeding, it must fly more than 3 m above the rice canopy;

[0028] 5. Light rolling to reduce damage: Harvest the previous crop between October 20th and October 30th. When harvesting, the degree of damage to the wheat seedlings must be minimized as much as possible; within 4 days after harvesting, all the straw must be transported out of the field; it is prohibited to use large machinery to enter the field to pick up and bale the straw;

[0029] 6. Dig through the internal and external ditch systems: Dig through the internal and external ditch systems as early as possible. Dig a vertical ditch every 4 m and a cross - ditch every 50 m in length. It is required that the internal and external ditch systems are complete and unobstructed, so that waterlogging can be drained, waterlogging can be reduced, and drought can be resisted;

[0030] 7. Early promotion and turning strong: Apply commercial organic fertilizer at more than 200 kg / 667m 2 and 45% (15 - 15 - 15) compound fertilizer at 30 kg / 667m 2 , zinc sulfate at 1 kg / 667m 2 , borax at 1 kg / 667m 2 within 5 days before and after the harvest of the previous crop;

[0031] 8. Applying ear and grain fertilizers: Do not apply green - turning and tillering fertilizers, but "catch the yellow patches" is allowed; apply urea in two times while it is raining from late March to early April, with a dosage of 15 - 20 kg / 667m 2 ;

[0032] 9. Comprehensive prevention and control: Conduct chemical weeding in mid - to late November (when the average daily temperature is stable above 7℃ and lasts for more than 5 days); the prevention and control targets in mid - November are small brown planthoppers, aphids and sheath blight; the prevention and control targets at the end of February are sheath blight and wheat spider mites; the prevention and control targets at the end of March are powdery mildew, sheath blight and aphids; conduct comprehensive prevention and control mainly for scab control more than 2 times during the full - heading and flowering stage, and concurrently control powdery mildew, rust, rice planthoppers, aphids.

[0033] Test and demonstration results:

[0034] 1. Built in the Rice - Wheat Science and Technology Comprehensive Demonstration Base in Jiangsu Province (in the rice - wheat original seed farm in Huaiyin District, Huai'an City) from 2019 to 2020: The demonstration field area is 0.60 hm 2 , clay soil, the variety is Huaimai 46, sown into the machine - transplanted japonica paddy field by interplanting on September 16th, and the seeding rate is 8.0 kg / 667m2 On October 20, the rice was harvested with a stubble height of 18 cm. Wheat and machine-transplanted japonica rice coexisted for 34 days. The straw was picked up and transported out on October 23. Base fertilizer was applied on October 24. In the case of severe autumn drought, urea was applied on November 4 and irrigation was immediately carried out. Because large machinery was used for harvesting rice, picking up straw and baling straw, the wheat seedlings were severely damaged by rolling. As a result, more than 30% of the area had late tillering and the number of panicles in the group was obviously insufficient. In areas with less rolling damage, tillering occurred early, the number of panicles in the group was sufficient and the panicle shape was larger. The final total average yield reached 513 kg / 667m 2 , which is slightly higher than the wheat sown after rice harvesting in the demonstration base. The results of this test site show that wheat interplanting under high temperature will not show symptoms of premature jointing or freezing in spring despite the warm winter and late spring cold.

[0035] 2. The inventor’s own vegetable garden built in Wuli Town, Huaiyin District, Anshi City from 2020 to 2021: area 12.0m 2 , sandy soil, variety Huaimai 46, sown into the topsoil between rows of autumn corn on September 11, with a sowing rate of about 5.0kg / 667m 2 On October 21, corn stalks and stubbles were cut off manually. Wheat and autumn corn coexisted for 40 days. On October 22, all base fertilizer was applied to the soil between wheat rows, and sufficient water was applied once after fertilization. No frost damage symptoms were shown in winter and spring. Because the wheat plants were not obviously damaged when the corn cobs were harvested manually and the corn stalks were cut off, and the base fertilizer was applied early and efficiently, effective tillering occurred vigorously, resulting in a large population in spring, and insufficient jointing and ear formation fertilizer was not applied, and foliar fertilizer was not implemented. The yield of the cutting square reached 607kg / 667m 2 , there was a wheat seedling in the field with 116 ears per plant. The results of this test site show that interplanting wheat under high temperature, as long as the right variety is selected, not only is its growth and development safe, but its single plant tillering and ear formation ability is also much higher than that of single wheat sown at the right time.

[0036] 3. Built in Tianli Family Farm, Hewang Township, Lianshui County in 2021-2022: Clay soil, Huaimai 46 variety, inter-seeded into hand-planted indica rice fields and direct-seeded japonica rice fields on September 20, with a hand-planted indica rice field area of ​​1.1 hm 2 The wheat sowing rate is 15kg / 667m 2 , direct-seeded rice field area 1.5hm 2 During the rice-wheat symbiosis period in the two fields, the wheat population density was appropriate and the individual growth conditions were in line with expectations. When the hand-planted indica rice was harvested on November 4 (i.e., harvested 25 days after the upper limit of the suitable sowing period, and the symbiosis period was 45 days), the wheel tracks were not obvious and the damage to the wheat seedlings was within the expected range. On November 5, when large-scale straw baling machinery entered the field for operation, a large number of wheel tracks with a depth of more than 17 cm were left. There were no wheel tracks near the edge of the field and the amount of residual wheat seedlings was slightly insufficient at 2000m2 was preserved, and the final actual yield was 473 kg / 667m 2 , which was 22.5 kg / 667m higher than the yield of the area where it was destroyed and reseeded 2 ; On November 24, the direct-seeded japonica rice was harvested (i.e., harvested 45 days after the upper limit of the suitable sowing period, with a symbiotic period of 65 days). Although manual labor was hired to collect and transport the straw out of the field, due to the too late harvesting date, strong seedlings before winter could not be cultivated, resulting in a small number of panicles per plant and insufficient panicles, and the actual yield was only 365 kg / 667m 2 . The results of this experimental site show that under high temperature, the relay-intercropped wheat is easier to ensure the seedling quantity of wheat during the symbiotic period than the existing relay-intercropping cultivation technology. However, only by timely harvesting the previous crop 10 - 20 days after the upper limit of the suitable sowing period, paying attention to reducing mechanical rolling damage, and applying fertilizers to promote weak seedlings early can strong seedlings before winter be cultivated and sufficient panicles be ensured.

Claims

1. A cultivation method for wheat sown in relay under high temperature and symbiotic with the previous crop for more than 30 days, characterized in that: including (1) Select suitable varieties for planting: Select semi-winter late-maturing varieties suitable for local planting, and spring and weak spring varieties are prohibited; (2) Seed treatment: Select a suitable seed coating agent for seed dressing to prevent pest and disease damage and other biological hazards during the co-growth period; (3) Timely interplanting: The upper limit of the suitable sowing period for wheat is October 10. Sow wheat seeds into the field 20 - 40 days before the upper limit of the suitable sowing period for wheat, that is, from September 1 to September 20. When the previous crop is rice, the surface of the paddy field for interplanting should be wet but without waterlogging. When the previous crop is dry field crops such as autumn corn and cotton, the wheat seeds must be sown into the topsoil during dry field interplanting. The population size of the previous crop must be moderate. When the population is too large to the extent that it is airtight and the ground cannot be seen at all from above, or when the population is too small to the extent that the ground between rows can be seen more than 1 m away along the row direction with the naked eye, interplanting cannot be carried out; (4)Reducing the variety and seeding rate: Determine the wheat seeding rate of 5.0 - 17.5 kg / 667m according to the harvesting date of the previous crop from October 20th to October 30th, the estimated degree of damage to the wheat seedlings by rolling, the availability of irrigation conditions during the wheat season, and the length of the co-growing period 2 ; (5) Light pressing to reduce damage: Harvest the previous crop 10 - 20 days after the upper limit of the suitable sowing period, that is, from October 20 to October 30, and try to reduce the damage to the wheat seedlings during harvesting; The whole amount of straw must be transported out of the field within 4 days after harvesting; (6) Early promotion and strengthening: Apply appropriate amounts of high-quality organic fertilizer, compound fertilizer and micronutrient fertilizer within 5 days after harvesting the previous crop.

2. The cultivation method for wheat sown in relay under high temperature and symbiotic with the previous crop for more than 30 days according to claim 1, characterized in that: In step (4), when the harvesting date is earlier, the estimated damage to the wheat seedlings by rolling is lighter, there is irrigation condition in the wheat season, and the co-growth period is long, the sowing rate of wheat takes a lower value. When the harvesting date is late, the estimated damage to the wheat seedlings by rolling is heavier, there is no irrigation condition in the wheat season, and the co-growth period is short, the sowing rate of wheat takes a higher value.

3. The cultivation method for wheat sown in relay under high temperature and symbiotic with the previous crop for more than 30 days according to claim 1, characterized in that: In step (4), unmanned aerial vehicles are used for sowing in the paddy field. When operating the unmanned aerial vehicle for sowing, it must fly more than 3 m above the rice canopy.

4. The cultivation method for wheat sown in relay under high temperature and symbiotic with the previous crop for more than 30 days according to claim 1, characterized in that: In step (5), it is prohibited to use large machinery to enter the field to pick up and bale straw.