Oilseed rape and milk vetch one-season double-harvest production method

Abstract

The invention provides a rape and astragalus sinicus one-season double-harvesting production method which comprises the following steps: step 1, ploughing and preparing soil within 5 days after one-season rice is harvested, and ditching according to the compartment width of 1.2 m + / -0.1 m and the ditch depth of 30 cm + / -2 cm; step 2, synchronous sowing from September 25 to October 10: direct sowing of rape: when the target yield is 120-135 kg / mu, the sowing rate of rape is 180-210 g / mu, and the sowing rate of Astragalus sinicus is 0.5-1.0 kg / mu; oilseed rape transplanting: when the target yield is 105-120 kg / mu, the transplanting density is 8500-10000 plants / mu and the astragalus sinicus is 1.2-1.6 kg / mu; 3, applying fertilizer: applying 6kg of nitrogen, 4kg of phosphorus (P2O5) and 5kg of potassium (K2O) to each mu in a basal manner, and applying 4kg of nitrogen to each mu in an overwintering period; 4, after combined harvesting from May 8th to May 12th in the next year, saline water with the density of 1.08 + / -0.01 g / cm is used for specific gravity sorting; compared with the prior art, the method has the following beneficial effects that light, temperature and water resources from October to May of the next year are fully utilized, the rape and the milk vetch are interplanted, and'double harvest of the rape and the milk vetch in one field 'and'double harvest of the rape and the milk vetch in one season' are achieved.

Description

Technical Field

[0001] The invention belongs to the field of composite planting, and in particular relates to a production method for harvesting rapeseed and Chinese milk vetch in one season. Background Art

[0002] Rapeseed is one of the most widely cultivated and important oil crops in my country. Its annual oil production occupies an important position among domestic oil crops and plays a vital role in ensuring the safety of edible oil in my country. The 2023 document pointed out that "comprehensive support measures for rapeseed should be coordinated, rice-oil rotation should be promoted, and winter fallow land should be vigorously developed and utilized to grow rapeseed." Rice-rapeseed rotation is one of the main cropping patterns in central and southern my country. Under this cropping pattern, the multiple cropping index is high, and the crops have a high demand for nutrients, resulting in serious soil nutrient depletion. The application of chemical fertilizers is one of the important measures to ensure high and stable crop yields. However, excessive and irrational application of chemical fertilizers not only fails to guarantee the effect of increasing crop yields, but also leads to high environmental risks and has a lasting negative impact on the human living environment and citizens' health.

[0003] In the southern rice-oil rotation area, the existing planting model has three major technical defects: 1. The contradiction of competitive crop yield reduction is prominent The growing seasons of rapeseed and Chinese milk vetch overlap significantly (October to May of the following year). Traditional intercropping results in: Competition for light resources: During the rapeseed row closure period (plant height > 80 cm), the shading rate reaches 65%-70%, causing the photosynthetically active radiation (PAR) of the Chinese milk vetch to fall below the compensation point (≤200 μmol / m²·s), and the biomass decreases by 38%-42%.

[0004] Competition for nutrients: The critical nitrogen requirement period of rapeseed seedlings (4-6 leaves) overlaps with the rapid growth period of milk vetch, and the consumption rate of soil available nitrogen is accelerated by 1.8 times, resulting in a reduction in yields of both crops.

[0005] Conventional solution: staggered sowing (sweet vetch delayed by 20 days).

[0006] Disadvantages: The shortened growth period of astragalus results in a 51% reduction in nitrogen fixation (<2kg N / mu), and spring rain during the flowering period causes the seed mold rate to be >30%.

[0007] 2. Low efficiency of seed mixing and sorting The physical properties of rapeseed (particle size 1.5-2.0mm) and milk vetch seeds (particle size 2.5-3.0mm) are similar: There is a large density overlap range: rapeseed 1.8-2.2g / cm³ vs. milk vetch seed 1.2-1.4g / cm³. The purity of traditional salt water sorting (density 1.05-1.10g / cm³) is only 85%-90%.

[0008] Severe mechanical damage: Combined harvesting causes the breakage rate of astragalus seeds to be >5% (national standard ≤1.5%).

[0009] Conventional solutions: manual sorting or air separation.

[0010] Disadvantages: The efficiency is as low as 0.8 mu / person / day (machine selection efficiency is 3 mu / h), and the loss of thousand-grain weight of milk vetch seeds reaches 8.7%.

[0011] 3. Soil sustainability deteriorates Rice-oil rotation multiple cropping index>2.0: Annual nutrient deficit: N consumption per season is 15.2±1.8kg / mu, relying on chemical fertilizers (accounting for >70% of nutrient sources).

[0012] Imbalance in straw return: C / N ratio of rapeseed straw return alone is > 90, and the decomposition rate constant k is 0.08 / d, which leads to increased soil nitrogen fixation (microbial nitrogen fixation > 30%).

[0013] Conventional solutions: increase fertilizer application or leave the land fallow for one season.

[0014] Disadvantages: Fertilizer use exceeds the safety threshold (250kg / ha·year), and fallow reduces land utilization by 40%.

[0015] How to resolve the contradiction between milk vetch and rapeseed for land, solve the problem of milk vetch seed production while achieving high and stable yields of rapeseed, and achieve the goal of improving soil fertility, increasing farmers' income, reducing chemical fertilizer use and increasing rice production, is of great significance to ensuring the dual increase of grain and oil and developing green and sustainable agriculture. Summary of the Invention

[0016] In view of the shortcomings of the existing technology, the purpose of the present invention is to provide a production method for harvesting rapeseed and Chinese milk vetch in one season, so as to solve the problems raised in the above background technology.

[0017] The present invention is achieved through the following technical solution: a production method for harvesting rapeseed and Chinese milk vetch in one season, comprising the following steps: Step 1: plough and prepare the land within 5 days after the first rice harvest, and dig furrows with a width of 1.2m±0.1m and a depth of 30cm±2cm; Step 2: Sow seeds simultaneously from September 25 to October 10: Direct seeding of rapeseed: When the target yield is 120-135kg / mu, sow rapeseed at a rate of 180-210g / mu and mix with milk vetch at a rate of 0.5-1.0kg / mu; Transplanting rapeseed: When the target yield is 105-120kg / mu, the transplanting density is 8500-10000 plants / mu + milk vetch 1.2-1.6kg / mu; Step 3, fertilization: basal application of nitrogen 6kg / mu, phosphorus 4kg P2O5 / mu, potassium 5kg K2O / mu, topdressing nitrogen 4kg / mu during the winter; Step 4: After the combined harvest from May 8th to 12th of the following year, the rice is sorted using brine with a density of 1.08±0.01g / cm³; Step 5: Return all the straw to the field, reducing nitrogen content in subsequent rice crops by 20%.

[0018] As a preferred embodiment, in step 2, the Chinese milk vetch is a late-maturing variety with a 1000-grain weight of 3.2-3.5 g, and the rapeseed is an upright variety with a plant height of 160-180 cm.

[0019] As a preferred embodiment, during direct seeding and mixed sowing in step 2, rapeseed and Chinese milk vetch seeds need to be premixed in a weight ratio of 1:5-1:10.

[0020] As a preferred embodiment, in step 4, the brine consists of water, NaCl and sodium carboxymethyl cellulose, with a density of 1.08 g / cm³ and a viscosity of 12-15 mPa·s.

[0021] As a preferred embodiment, in step 5, when returning straw to the field, the biomass of the Chinese milk vetch is ≥800 kg / mu, and the mass ratio of rapeseed to Chinese milk vetch straw is 1:0.6-1:1.

[0022] As a preferred embodiment, the combine harvester used in step 4 is equipped with a vibrating screen (aperture 2.0 mm) and a specific gravity seed selection trough with an inclination angle of 28°±2°.

[0023] As a preferred embodiment, the vibration screen frequency is 9 Hz±0.5 Hz, and the air flow velocity is 2.8 m / s±0.2 m / s.

[0024] As a preferred embodiment, the rapeseed plant height H1 and the Chinese milk vetch plant height H2 are regulated to meet the following conditions: 60 cm ≤ H1-H2 ≤ 80 cm, so that the light transmittance of the Chinese milk vetch canopy reaches 45%-50%.

[0025] By adopting the above technical solution, the present invention has the following beneficial effects: fully utilizing the light, temperature, and water resources from October to May of the following year, intercropping rapeseed with Chinese milk vetch, and achieving "double harvests from one field" and "double harvests from one season" of rapeseed and Chinese milk vetch. On the one hand, fertilizing the rapeseed season promotes the growth of Chinese milk vetch, and the rapeseed stems provide support for its growth, promoting the increase of Chinese milk vetch biomass and nitrogen fixation, achieving the goal of soil fertility. At the same time, by adjusting the density of Chinese milk vetch and rapeseed, a high yield of both rapeseed and Chinese milk vetch is achieved. On the basis of ensuring stable rapeseed production, an extra season of Chinese milk vetch seeds can be harvested, achieving the multiple goals of improving soil fertility, achieving high and stable yields, and increasing planting efficiency. DETAILED DESCRIPTION

[0026] The following is a clear and complete description of the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only some of the embodiments of the present invention, not all of them. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0027] The present invention provides a technical solution: a production method for harvesting both rapeseed and Chinese milk vetch in one season, comprising the following steps: Step 1: plough and prepare the land within 5 days after the first rice harvest, and dig furrows with a width of 1.2m±0.1m and a depth of 30cm±2cm; Step 2: Sow seeds simultaneously from September 25 to October 10: Direct seeding of rapeseed: When the target yield is 120-135kg / mu, sow rapeseed at a rate of 180-210g / mu and mix with milk vetch at a rate of 0.5-1.0kg / mu; Transplanting rapeseed: When the target yield is 105-120kg / mu, the transplanting density is 8500-10000 plants / mu + milk vetch 1.2-1.6kg / mu; Step 3, fertilization: basal application of nitrogen 6kg / mu, phosphorus 4kg P2O5 / mu, potassium 5kg K2O / mu, topdressing nitrogen 4kg / mu during the winter; Step 4: After the combined harvest from May 8th to 12th of the following year, the rice is sorted using brine with a density of 1.08±0.01g / cm³; Step 5: Return all the straw to the field, reducing nitrogen content in subsequent rice crops by 20%.

[0028] In step 2, the Chinese milk vetch is a late-maturing variety with a thousand-grain weight of 3.2-3.5 g, and the rapeseed is an upright variety with a plant height of 160-180 cm.

[0029] When direct seeding and mixing in step 2, rapeseed and milk vetch seeds need to be pre-mixed in a weight ratio of 1:5-1:10.

[0030] In step 4, the brine consists of water, NaCl and sodium carboxymethyl cellulose, with a density of 1.08 g / cm³ and a viscosity of 12-15 mPa·s.

[0031] In step 5, when returning straw to the field, the biomass of the astragalus is ≥800 kg / mu, and the mass ratio of rapeseed to astragalus straw is 1:0.6-1:1.

[0032] The combine harvester used in step 4 was equipped with a vibrating screen (aperture 2.0 mm) and a gravity seed selection trough with an inclination angle of 28°±2°.

[0033] The vibration screen frequency is 9Hz±0.5Hz, and the air flow velocity is 2.8m / s±0.2m / s.

[0034] By regulating the rapeseed plant height H1 and the milk vetch plant height H2 to meet the following conditions: 60cm ≤ H1-H2≤ 80cm, the light transmittance of the milk vetch canopy can reach 45%-50%.

[0035] The advantages and technical effects of the present invention are as follows: 1. It resolves the conflict between milk vetch and rapeseed for land, achieving a combination of fertilization and maintenance of cultivated land without affecting rapeseed production. 2. It achieves high and stable rapeseed yields while simultaneously increasing milk vetch seed production in the same field, ensuring oilseed crop production, resolving milk vetch seed shortages, and increasing farmers' income. 3. After harvest, the simultaneous return of milk vetch straw (with a low carbon / nitrogen ratio of 15-20:1) and rapeseed straw (with a high carbon / nitrogen ratio of 90-130:1) to the field balances the carbon / nitrogen ratios of the individual straw types. The milk vetch straw helps accelerate the composting of the rapeseed straw, thereby providing effective nutrients for the subsequent rice crop. 4. Fertilizing rapeseed promotes the growth of milk vetch. Furthermore, the upright growth of rapeseed in the middle and late stages provides support for the milk vetch, facilitating full utilization of field light and temperature resources and promoting its growth. 5. The rhizobia in milk vetch's roots fix nitrogen from the air. Their growth improves the soil microbial environment, enriches species diversity, and is also beneficial to rapeseed growth. 6. Rapeseed and milk vetch have different root diameters and shapes, and their root systems grow to different depths. Their complementary nature improves and coordinates their biological tillage functions, fostering a more optimal soil structure. 7. Milk vetch is a clean, high-quality natural organic fertilizer resource. It enriches the soil, boosts rapeseed and subsequent rice yields, and improves the quality of both rapeseed and rice. 8. The flowering periods of rapeseed and milk vetch overlap, resulting in a longer flowering period and richer coloration than single species, providing a more beautiful landscape and aesthetic enjoyment, and improving the quality of the ecological environment. 9. During the harvest at maturity, in addition to the harvested milk vetch seeds, a portion is retained for future use. This allows for a single sowing cycle, with no need for sowing or appropriate reseeding for years. This reduces labor intensity and saves on milk vetch seed and sowing costs. 10. Intercropping and mixed planting of rapeseed and milk vetch increases the amount of straw returned to the field, and the amount of chemical fertilizer that can be replaced by subsequent crops and the amount of chemical fertilizer applied can be further increased, which is beneficial to saving fertilizer and reducing emissions in rice fields and has a good ecological effect. As an example of the present invention, in 2022, 35 mu (approximately 1.5 acres) of rice fields were selected in Heba Village, Xinqiaohe Town, Ziyang District, Yiyang City. After the rice harvest on October 5, 2022, the fields were plowed and mechanical trenching was used to create trenches and perimeter ditches. Side ditches were spaced 1.2 meters apart, 0.35 meters wide, and 30 centimeters deep, with the side and perimeter ditches interconnected. Milk vetch seeds and rapeseed seeds were sown simultaneously using drones. The milk vetch variety was Xiangzi No. 1, with a sowing rate of 1.5 kg / mu. The rapeseed variety was Fengyou 737, with a sowing rate of 150 g / mu. Nitrogen, phosphorus, and potassium fertilizers were applied at 10 kg N / mu, 4 kg P₂O₅ / mu, and 5 kg K₂O / mu, respectively. Borax was applied at 1 kg / mu. Nitrogen fertilizer was applied at a rate of 60% base fertilizer and 40% winter fertilizer, with the remaining fertilizers applied as a single base fertilizer. Ditches were cleaned once in March to facilitate field drainage and irrigation. In early May, rapeseed harvesters were used to simultaneously harvest and sort both milk vetch and rapeseed seeds, achieving "two harvests per machine," "two harvests per season," and "two harvests per field." After the seeds were harvested, rapeseed and milk vetch straw were returned to the fields to provide nutrients for the following rice crop. On-site yield measurements were conducted on 2.08 mu of land, and the rapeseed yield using this technology was 252.51 kg (121.40 kg / mu) and 83.82 kg (40.30 kg / mu) respectively. This achieved stable rapeseed yields and an additional milk vetch seed harvest. The milk vetch straw also provided an additional nitrogen source of approximately 4 kg / mu, effectively saving nutrients and fertilizer.

[0036] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A production method for harvesting both rapeseed and Chinese milk vetch in one season, characterized in that: The following steps are involved: Step 1: plough and prepare the land within 5 days after the first rice harvest, and dig furrows with a width of 1.2m±0.1m and a depth of 30cm±2cm; Step 2: Sow seeds simultaneously from September 25 to October 10: Direct seeding of rapeseed: When the target yield is 120-135kg / mu, sow rapeseed at a rate of 180-210g / mu and mix with milk vetch at a rate of 0.5-1.0kg / mu; Transplanting rapeseed: When the target yield is 105-120kg / mu, the transplanting density is 8500-10000 plants / mu + milk vetch 1.2-1.6kg / mu; Step 3, fertilization: basal application of nitrogen 6kg / mu, phosphorus 4kg P2O5 / mu, potassium 5kg K2O / mu, topdressing nitrogen 4kg / mu during the winter; Step 4: After the combined harvest from May 8th to 12th of the following year, the rice is sorted using brine with a density of 1.08±0.01g / cm³; Step 5: Return all the straw to the field, reducing nitrogen content in subsequent rice crops by 20%.

2. The method for producing rapeseed and Chinese milk vetch in one season as claimed in claim 1, wherein: In step 2, the Chinese milk vetch is a late-maturing variety with a thousand-grain weight of 3.2-3.5 g, and the rapeseed is an upright variety with a plant height of 160-180 cm.

3. The method for producing rapeseed and Chinese milk vetch in one season according to claim 1, wherein: When direct seeding and mixing in step 2, rapeseed and milk vetch seeds need to be pre-mixed in a weight ratio of 1:5-1:

10.

4. The method for producing rapeseed and Chinese milk vetch in one season according to claim 1, wherein: In step 4, the brine consists of water, NaCl and sodium carboxymethyl cellulose, with a density of 1.08 g / cm³ and a viscosity of 12-15 mPa·s.

5. The method for producing rapeseed and Chinese milk vetch in one season according to claim 1, wherein: In step 5, when returning straw to the field, the biomass of the astragalus is ≥800 kg / mu, and the mass ratio of rapeseed to astragalus straw is 1:0.6-1:

1.

6. The method for producing rapeseed and Chinese milk vetch in one season according to claim 1, wherein: The combine harvester used in step 4 was equipped with a vibrating screen (aperture 2.0 mm) and a gravity seed selection trough with an inclination angle of 28°±2°.

7. The method for producing rapeseed and Chinese milk vetch in one season according to claim 6, wherein: The vibration screen frequency is 9Hz±0.5Hz, and the air flow velocity is 2.8m / s±0.2m / s.

8. The method for producing rapeseed and Chinese milk vetch in one season according to claim 1, wherein: By regulating the rapeseed plant height H1 and the milk vetch plant height H2 to meet the following conditions: 60cm ≤ H1-H2≤ 80cm, the light transmittance of the milk vetch canopy can reach 45%-50%.