Planting method for winter rape straw mulching no-tillage direct seeding

Abstract

The invention relates to the technical field of agricultural planting. The invention provides a winter rape straw mulching no-tillage direct seeding planting method which comprises the following steps: (1) collecting straws on the earth surface of a to-be-planted area, ditching on the earth surface of the to-be-planted area, and constructing a planting bed; (2) precisely sowing on the planting bed, and covering the straw collected in the step (1) on the surface. The three-layer structure of the subsoil layer, the seed layer and the straw covering layer is innovatively constructed, and the problem of'high seedlings' caused by seed suspension in the traditional straw returning mode is effectively solved. According to the method, the straw covering layer is used for preserving heat and soil moisture and inhibiting weed and bird damage, meanwhile, the subsoil layer is used for ensuring that seed implantation is stable, the emergence rate and the overwintering survival rate of the oilseed rape are remarkably increased, and cooperation of straw resource utilization and high yield and high efficiency of the oilseed rape in the rice-oil rotation cropping mode is achieved.

Description

Technical Field

[0001] This invention relates to the field of agricultural planting technology, and in particular to a method for direct seeding of winter rapeseed using straw mulch and no-till cultivation. Background Technology

[0002] Rapeseed, as my country's largest oilseed crop and one of the four major oilseed crops that can be planted in winter, is of strategic significance for ensuring the country's edible oil supply security. However, with the popularization of high-yield rice cultivation techniques, the total amount of rice straw has increased significantly. To reduce the workload of harvesters, rice straw is usually left whole during harvest without being shredded, resulting in a large amount of long, intertwined whole stalks covering the field surface. This physical barrier of straw severely hinders the operation of agricultural machinery such as rotary tillers, ditchers, and seeders.

[0003] Currently, the rice-rapeseed or rice-rice-rapeseed rotation planting model is implemented in southern my country. Winter rapeseed planting in this model suffers from a short rice-rapeseed cropping period. If the late rice harvest is delayed, the rapeseed's growing season is insufficient, making it difficult for strong seedlings to survive the winter. This problem is even more pronounced in areas implementing the rice-rice-rapeseed triple cropping system. To address this, many regions are actively promoting rapeseed seedling transplanting techniques (such as mechanized transplanting of rapeseed mat-like seedlings) to advance seedling cultivation and transplanting, seizing the opportune time for planting. However, as mentioned above, the increased straw in rice stubble fields makes it difficult to create suitable fields for rapeseed transplanting, and rapeseed seedling cultivation requires more manpower and resources, resulting in poor economic returns for rapeseed cultivation.

[0004] Therefore, it is essential to provide a winter rapeseed straw mulching no-till direct seeding method that can transform the aforementioned rice straw problems into favorable conditions for rapeseed seed germination and seedling growth, thereby enhancing the overall benefits of the rice-rapeseed rotation system. Summary of the Invention

[0005] The purpose of this invention is to provide a method for no-till direct seeding of rapeseed under straw mulch. By constructing a three-layer structure of "subsoil-seed-straw", it not only solves the problem of seed suspension, but also significantly improves the germination rate and overwintering survival rate of rapeseed, realizing the synergistic effect of straw resource utilization and high yield and efficiency of rapeseed under the rice-rapeseed rotation mode.

[0006] To achieve the above-mentioned objectives, the present invention provides the following technical solution: This invention provides a method for no-till direct seeding of winter rapeseed covered with straw, comprising the following steps: (1) Collect straw from the surface of the area to be planted and dig trenches on the surface of the area to be planted to construct planting beds; (2) Precision seeding is carried out on the planting bed and the straw collected in step (1) is covered on the surface.

[0007] As a preferred method, the method of collecting surface straw in the planting area in step (1) includes collecting only the surface straw in the planting area while keeping the stubble without crushing, or collecting both the surface straw and the crushed stubble in the planting area at the same time.

[0008] As a preferred method, when the method of collecting surface straw in the planting area is to collect only the surface straw and leave the stubble uncrushed, the height of the stubble is 30-40cm; when the method of collecting surface straw in the planting area is to collect both the surface straw and the crushed stubble, the length of the crushed stubble is 5-10cm.

[0009] Preferably, the planting bed is constructed using the soil from the bottom of the trench, with a soil cover of 16-28 kg / m². 2 .

[0010] Preferably, the thickness of the soil at the bottom of the planting bed trench is 2-3 cm, and the width of the planting bed is 1.5-2.5 m.

[0011] Preferably, the amount of seeds sown in step (2) is 350-500g / mu.

[0012] Preferably, the straw mulch amount in step (2) is 250-500 g / m². 2 .

[0013] Preferably, the rapeseed is an early-maturing, cold-resistant, and lodging-resistant variety.

[0014] By adopting the above technical solution, the present invention has the following beneficial effects: This invention innovatively constructs a three-layer structure: a subsoil layer, a seed layer, and a straw covering layer. This significantly improves seedling quality and stress resistance, overcoming the drawback of traditional direct seeding where seeds are mixed with straw. By digging trenches and laying a layer of moist, fine subsoil, the seeds are ensured to be sown directly on the soil, solving the problem of "leggy seedlings" caused by seeds being suspended in the air. This promotes rapid root development and enhances lodging resistance. The subsequent straw covering layer creates a greenhouse-like microenvironment, which reduces soil moisture evaporation (moisture retention) and buffers against low winter temperatures (heat preservation), thus ensuring the rapeseed's safe overwintering.

[0015] The planting method described in this invention has a flexible operation mode and strong adaptability. It fully considers areas where stubble is not crushed and areas where it is completely returned to the field. It has good inclusiveness for the treatment of previous rice stubble. Whether only straw is collected without crushing the stubble or both straw is collected and the entire stubble is crushed, the planting scheme described in this invention can be applied and can achieve the technical effects described in this invention. Attached Figure Description

[0016] Figure 1This is a schematic diagram of the "soil-seed-straw" planting model described in this invention. Detailed Implementation

[0017] This invention provides a method for no-till direct seeding of winter rapeseed under straw mulch (e.g.) Figure 1 As shown), it includes the following steps: (1) Collect straw from the surface of the area to be planted and dig trenches on the surface of the area to be planted to construct planting beds; (2) Precision seeding is carried out on the planting bed and the straw collected in step (1) is covered on the surface.

[0018] In this invention, the straw from the previous rice crop is collected after harvesting, leaving the soil surface of the planting area exposed. The methods for collecting the previous rice straw include collecting only the surface straw of the planting area while leaving the stubble intact, or collecting both the surface straw and the shredded stubble simultaneously.

[0019] In this invention, when the method of collecting surface straw in the planting area is to collect only the surface straw while leaving the stubble uncrushed, the height of the stubble is preferably 30-40cm, more preferably 32-38cm, and even more preferably 35cm; when the method of collecting surface straw in the planting area is to collect both surface straw and crushed stubble, the length of the crushed stubble is preferably 5-10cm, more preferably 6-9cm, and even more preferably 8cm.

[0020] In this invention, mechanical (double-disc ditching machine) ditching is performed on the surface of the planting area (or between stubble rows). The soil from the ditch bottom is then evenly spread and covered onto the ridges on both sides of the ditch, forming a flat sowing subsoil layer, which constitutes the planting bed. The preferred soil coverage of the ditch bottom soil in this invention is 16-28 kg / m². 2 A further preferred value is 21-24 kg / m³. 2 A further preferred value is 22 kg / m³. 2 .

[0021] In this invention, when the method of collecting surface straw in the planting area is to collect only the surface straw in the planting area while keeping the stubble intact and not crushing it, the scattered soil will fall on the surface between the stubble, which can still form a planting bed and does not affect the logic of this invention.

[0022] In this invention, the thickness of the soil at the bottom of the planting bed trench is preferably 2-3 cm, more preferably 2.1-2.6 cm, and even more preferably 2.1-2.2 cm; the width of the planting bed is preferably 1.5-2.5 m, more preferably 1.8-2.2 m, and even more preferably 2 m. The thickness of the planting bed in this invention is determined according to the trenching depth.

[0023] In this invention, the preferred method of applying a slow-release compound fertilizer specifically for rapeseed before planting is to use a dosage of 40-50 g / m². 2 A further preferred value is 42-48 g / m³. 2 A further preferred value is 45g / m 2 .

[0024] In this invention, rapeseed seeds are precision-sown on a planting bed. The preferred sowing amount is 420-480g / mu, more preferably 430-460g / mu, and even more preferably 450g / mu.

[0025] In this invention, after sowing, the straw collected in step (1) is used as a surface covering, and the straw covering amount is preferably 250-500 g / m². 2 A further preferred value is 300-450 g / m³. 2 A further preferred value is 400g / m 2 .

[0026] In this invention, the rapeseed is an early-maturing, cold-resistant, and lodging-resistant variety.

[0027] The technical solutions provided by the present invention will be described in detail below with reference to the embodiments, but they should not be construed as limiting the scope of protection of the present invention.

[0028] Example 1

[0029] A method for no-till direct seeding of winter rapeseed covered with straw, the steps of which are as follows: (1) Collect the straw in the field after the previous rice harvest, and only collect the straw on the surface of the area to be planted, leaving the stubble exposed; the height of the stubble is 35cm. (2) Mechanical trenching is carried out on the surface of the planting area (or between stubble rows). The soil from the trench bottom is evenly spread and covered on the ridges on both sides of the trench to form a flat sowing bottom soil layer, which is the planting bed. The soil coverage of the trench bottom soil is 22 kg / m². 2 The soil thickness at the bottom of the planting bed trench is 2.1 cm, and the width is 2 m; (3) Precision sowing of rapeseed seeds at a sowing rate of 450g / mu on the planting bed; (4) After sowing, apply 400g / m 2 The amount of coverage is the amount of straw covered in step (1).

[0030] Example 2

[0031] A method for no-till direct seeding of winter rapeseed covered with straw, the steps of which are as follows: (1) Collect the straw in the field after the previous rice harvest, collect only the straw on the surface of the area to be planted and leave the stubble uncrushed, so that the surface of the area to be planted is exposed; the height of the stubble is 30cm. (2) Mechanical trenching is carried out on the surface of the planting area (or between stubble rows). The soil from the trench bottom is evenly spread and covered on the ridges on both sides of the trench to form a flat sowing bottom soil layer, which is the planting bed. The soil coverage of the trench bottom soil is 16 kg / m². 2 The soil thickness at the bottom of the planting bed furrow is 2cm, and the width is 1.5m; (3) Precision sowing of rapeseed seeds at a sowing rate of 420g / mu on the planting bed; (4) After sowing, apply 250g / m 2 The amount of coverage is the amount of straw covered in step (1).

[0032] Example 3

[0033] A method for no-till direct seeding of winter rapeseed covered with straw, the steps of which are as follows: (1) Collect the straw in the field after the previous rice harvest, only collect the straw on the surface of the area to be planted, and leave the stubble uncrushed, so that the surface of the area to be planted is exposed; the height of the stubble is 40cm. (2) Mechanical trenching is carried out on the surface of the planting area (or between stubble rows). The soil from the trench bottom is evenly spread and covered on the ridges on both sides of the trench to form a flat sowing bottom soil layer, which is the planting bed. The soil coverage of the trench bottom soil is 28 kg / m². 2 The soil thickness at the bottom of the planting bed trench is 3cm, and the width is 2.5m; (3) Sow rapeseed seeds in the planting bed with precision at a sowing rate of 480g / mu. (4) After sowing, apply 500g / m 2 The amount of coverage is the amount of straw covered in step (1).

[0034] Example 4

[0035] A method for no-till direct seeding of winter rapeseed covered with straw, the steps of which are as follows: (1) Collect the straw in the field after the previous rice harvest, and collect the straw and crushed stubble on the ground in the area to be planted, so that the ground in the area to be planted is exposed; the length of the crushed stubble is 8cm. (2) Mechanical trenching is carried out on the surface of the planting area (or between stubble rows). The soil from the trench bottom is evenly spread and covered on the ridges on both sides of the trench to form a flat sowing bottom soil layer, which is the planting bed. The soil coverage of the trench bottom soil is 22 kg / m².2 The soil thickness at the bottom of the planting bed trench is 2.2cm, and the width is 2m; (3) Precision sowing of rapeseed seeds at a sowing rate of 450g / mu on the planting bed; (4) After sowing, apply 400g / m 2 The amount of coverage is the amount of straw covered in step (1).

[0036] Experimental Example 1

[0037] An experiment was conducted in the Southern Rice-Oil Rotation Area of ​​Xiejia Village, Xibianshanxia, ​​Xinjian District, Nanchang City, Jiangxi Province. The rapeseed variety used was Ganyouza 906, an early-maturing variety promoted by Jiangxi Province. Based on Example 1, the effects of different planting structure patterns (positional relationships of straw (J), soil (T), and seeds (Z)) and different amounts of straw (G) and soil cover (R) on the seedling rate and the rate of "leggy seedlings" of rapeseed were investigated.

[0038] (a) JTZ mode

[0039] In the rice-oilseed rotation area in the south, there are two conventional methods for planting winter rapeseed: sowing first and then furrowing, and furrowing first and then ridging before sowing. If the method of furrowing first and then ridging before sowing is used, it forms a three-layer structure of "straw-soil-seed", which is abbreviated as JTZ.

[0040] To investigate the optimal amount of straw and soil cover required for rapeseed under the best growing conditions, a two-factor experiment was conducted, involving both soil and straw. The straw amount was set at 100 g / m². 2 250g / m 2 400g / m 2 These are designated as G1, G2, and G3 respectively; the soil cover levels are 16 kg / m². 2 22kg / m 2 28kg / m 2 Let them be denoted as R1, R2, and R3 respectively.

[0041] The straw quantity level was determined by observing the straw distribution in the field after the actual harvest of late rice, resulting in three levels: upper, middle, and lower. The soil cover quantity was determined by observing the soil distribution based on the different ditching depths of the double-disc ditching machine, resulting in three levels: upper, middle, and lower.

[0042] The soil moisture content was measured to be 20%-30%, and the sampling points for each treatment were selected. Excluding soil cover and straw content, other treatments were consistent with the sowing treatments used by local farmers. Rapeseed was planted at a density of 450g / mu using precision artificial sowing to ensure even seed distribution. Each treatment was replicated three times, and each treatment group was tested in a 1m × 1m field. Rapeseed data for each treatment were measured every 3 days after sowing, continuing until the cotyledons fell off and the seedlings had 3-5 true leaves, indicating they could safely overwinter. This was considered the final seedling stage.

[0043] Table 1. Rapeseed seedling rate and "leggy seedling" rate in different treatment groups.

[0044] As shown in Table 1, under the JTZ model, the presence of a large amount of straw in the lower layer blocked capillary water uptake, resulting in poor soil water retention and making it difficult for seed roots to penetrate the straw layer and reach the subsoil. The experimental results showed that the seedling rate was generally low in all treatments (the highest being only 41.27%), and fluctuated greatly depending on the amount of straw, making it difficult to meet high-yield requirements.

[0045] (II) JZT Mode

[0046] In the rice-oilseed rotation areas in the south, if winter rapeseed is planted by sowing first and then digging furrows, it forms a three-layer structure of "straw-seed-soil", abbreviated as JZT.

[0047] Similar to (a), the straw content level is set at 100g / m³. 2 250g / m 2 400g / m 2 These are designated as G1, G2, and G3 respectively; the soil cover levels are 16 kg / m². 2 22kg / m 2 28kg / m 2 The results were denoted as R1, R2, and R3. The locations of the sampling points for each treatment were selected. Excluding soil cover and straw amount, the other treatments were consistent with the local farmers' sowing practices. Rapeseed was planted at a density of 450 g / mu using precision artificial sowing to ensure even seed distribution. Each treatment was replicated three times, and each treatment group was tested in a 1m × 1m field. The seedling emergence rate and the rate of "leggy" seedlings were analyzed.

[0048] Table 2. Rapeseed seedling rate and "leggy seedling" rate in different treatment groups.

[0049] The results are shown in Table 2. Under the JZT mode, the rate of "tall seedlings" was extremely high. As the soil cover increased (R1 to R3), the seedling rate actually decreased. This is because the excessively thick soil cover, combined with the susceptibility of the bottom straw, resulted in high resistance to seed germination and difficulty in water absorption. Although the seedling rate was acceptable under low soil cover (R1), the rate of tall seedlings was as high as about 40%.

[0050] (III) The TZJ mode of this invention

[0051] In the rice-oilseed rotation area in the south, the amount of straw greatly affects the existing rapeseed planting. Now, by utilizing the crushed straw, a three-layer structure of "soil-seed-straw" is formed, which is abbreviated as TZJ.

[0052] Similar to (a), the straw content level is set at 100g / m³. 2 250g / m 2 400g / m 2 These are designated as G1, G2, and G3 respectively; the soil cover levels are 16 kg / m². 2 22kg / m 2 28kg / m 2 The results were denoted as R1, R2, and R3. The locations of the sampling points for each treatment were selected. Excluding soil cover and straw amount, the other treatments were consistent with the local farmers' sowing practices. Rapeseed was planted at a density of 450 g / mu using precision artificial sowing to ensure even seed distribution. Each treatment was replicated three times, and each treatment group was tested in a 1m × 1m field. The seedling emergence rate and the rate of "leggy" seedlings were analyzed.

[0053] Table 3. Rapeseed seedling rate and "leggy seedling" rate in different treatment groups.

[0054] The results are shown in Table 3. The overall seedling survival rate of the planting method described in this invention is significantly better than that of the JTZ and JZT models. Under high straw content G3 (400g / m²), the seedling survival rate was also significantly higher. 2 Under the specified conditions, the seedling survival rates of treatments R1 and R2 reached 56.78% and 53.03%, respectively, significantly higher than the control group. This indicates that the straw cover layer played a good role in moisture retention and protection.

[0055] In summary, the rapeseed seedling emergence rate of the three-layer structure "soil-seed-straw (TZJ)" described in this invention is generally good under different straw and soil amounts. The rapeseed seedling emergence rate under the three-layer structure "straw-soil-seed (JTZ)" is generally poor, but the rate of "leggy seedlings" is low under soil amounts R1 and R2. The rapeseed seedling emergence rate under the three-layer structure "straw-seed-soil (JZT)" is generally high, with a better emergence rate under soil amount R1 and worse under soil amounts R2 and R3. From the above results, it can be seen that, from the perspective of seedling emergence rate, covering rapeseed with crushed straw has a significant protective effect on seedling emergence. Table 3 shows that the rapeseed seedling emergence rates of treatments R1G3 and R2G3 are both high, but considering the leggy seedlings and actual planting conditions, the R2G3 treatment is preferred for planting winter rapeseed to obtain better overall benefits.

[0056] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for cultivating winter rape straw mulching no-tillage direct seeding, characterized in that, The method comprises the following steps: (1) collecting straw on the surface of the area to be planted and digging a ditch on the surface of the area to be planted to form a planting bed; (2) precision seeding on the planting bed and covering the surface with the straw collected in step (1).

2. The method of planting of claim 1, wherein, The method for collecting the straw on the surface of the area to be planted comprises only collecting the straw on the surface of the area to be planted without crushing the stubble or simultaneously collecting the straw on the surface of the area to be planted and crushing the stubble.

3. The method of planting of claim 2, wherein, When the method for collecting the straw on the surface of the area to be planted is only collecting the straw on the surface of the area to be planted without crushing the stubble, the height of the stubble is 30-40 cm. When the method for collecting the straw on the surface of the area to be planted is simultaneously collecting the straw on the surface of the area to be planted and crushing the stubble, the length of the crushed stubble is 5-10 cm.

4. The method of planting of claim 1, wherein, A planting bed is constructed using the trench bottom soil produced by trenching, and the soil covering amount of the trench bottom soil is 16-28 kg / m 2 .

5. The method of planting of claim 4, wherein, The thickness of the soil at the bottom of the ditch of the planting bed is 2-3 cm, and the width of the planting bed is 1.5-2.5 m.

6. The method of planting of claim 1, wherein, The amount of seeding in step (2) is 350-500 g per mu.

7. The method of planting of claim 1, wherein, Step (2) straw covering amount is 250-500 g / m 2 .

8. The method of planting of claim 1, wherein, The rape is an early-maturing, cold-tolerant and lodging-resistant variety.

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