Annual crop rotation method for soybeans, rice and oilseed rapes

Abstract

The invention provides an annual crop rotation method for soybeans, rice and oilseed rapes, which comprises the following steps: continuously cropping soybeans, rice and oilseed rapes (spring soybean-late rice-oilseed rape annual crop rotation system) on the same land in the same year (within 12 months), and regulating and controlling rhizosphere local nutrients of crops by adopting a lateral deep fertilization technology, so that the soil health is improved, and the crop yield is increased. The multiple cropping index is increased, high yield of grain and oil feed is promoted, and multiple improvements of environmental and economic benefits are realized. According to the technical scheme, through crop rotation, a single rice continuous cropping mode is broken through, extension of root systems in the growth process of soybeans and oilseed rapes can be utilized, the soil structure is improved, the air permeability and the water-retaining property of soil are enhanced, an excellent growth environment is provided for succeeding crops, the comprehensive yield of rice, soybeans and oilseed rapes is increased, and high economic benefits are achieved; in addition, in a crop rotation system, application of lateral deep fertilization is closely combined with growth characteristics of soybeans, rice and oilseed rapes, and the goals of increasing yield and efficiency, saving cost and protecting environment are achieved.

Description

Technical Field

[0001] The invention relates to the field of planting technology, in particular to an annual crop rotation method of soybean, rice and rapeseed. Background Art

[0002] The middle and lower reaches of the Yangtze River have abundant light, temperature and water resources, and superior climatic conditions. They have significant advantages such as sufficient light radiation, an average annual accumulated temperature of more than 10℃ and more than 4500℃, and an annual rainfall of more than 800 mm. The region is an important rice producing area in my country. The frost-free period suitable for safe rice production is 186 to 236 days, forming a rice-based planting pattern. In addition, soybeans, as a short-day, thermophilic crop, have 195 to 210 days of growth in the region, and also have good growth conditions, which can form a rotation complement with rice. Rapeseed, as my country's second largest oil crop and the only oil crop in winter, plays an important role in the middle and lower reaches of the Yangtze River. Planting rapeseed can not only effectively utilize winter land resources, but also improve soil structure and fertilize soil fertility. It is one of the typical representatives of "using land to support land" and "combining use and support". These natural conditions have provided the middle and lower reaches of the Yangtze River with the basic conditions for the production of rice, soybeans and rapeseed. Multiple cropping of cultivated land is a common agricultural planting system in China, which is of great significance to increasing the total crop output. In the context of limited arable land resources in my country, improving the multiple cropping index is an effective way to ensure my country's food security.

[0003] However, for a long time, the middle and lower reaches of the Yangtze River have mainly relied on a single continuous rice cropping model, accompanied by high-intensity fertilizer input, which has led to a series of soil and environmental problems. Long-term continuous rice cropping has gradually compacted the soil, affecting soil structure and fertility, and causing problems such as nitrogen loss and increased greenhouse gas emissions. These factors not only restrict the increase in rice yields, but also affect the quality of rice. In addition, the deterioration of soil health has also led to severe challenges to the sustainability of agricultural production.

[0004] In order to solve the above problems, existing technologies have made some attempts. For example, technical measures such as variety screening, fertilizer-saving experiments, and soil cultivation have significantly improved the fertility of cultivated land, reduced environmental pollution, and improved resource utilization efficiency, and have played a positive role in improving product quality and increasing comprehensive benefits. However, although these individual technologies have achieved certain results, the grain-soybean-oil rotation system with higher ecological and economic benefits has not yet been widely used. Increasing the multiple cropping index and implementing annual rotation of soybeans, rice, and rapeseed can also alleviate the conflict between grain crops and cash crops for land to a certain extent. Especially in the middle and lower reaches of the Yangtze River, the annual efficient rotation cultivation technology of rice, soybeans, and rapeseed based on full mechanization is still in the initial exploration stage, and a mature plan for large-scale promotion and application has not yet been formed.

[0005] In view of this, it is necessary to design an improved annual rotation method of soybean, rice and rapeseed to solve the above problems. Summary of the invention

[0006] The purpose of the present invention is to provide a year-round crop rotation method for soybean, rice and rapeseed.

[0007] To achieve the above-mentioned purpose, the present invention provides a method for annual crop rotation of soybean, rice and rapeseed, which is applicable to the middle and lower reaches of the Yangtze River and comprises the following steps:

[0008] S1. Sow soybeans in early May. The sowing method is direct seeding. Sow in holes with a hole spacing of 10-13 cm and a row spacing of 40-43 cm. Sow 2-3 seeds per hole. The seed rate is 7-9 kg per mu and the sowing depth is 3-5 cm. After sowing, use a mixture of isothiocarb and glyphosate for closed weeding.

[0009] S2. 2-3 inter-row cultivations were carried out before closing the soybean rows. In the second node stage of soybeans, topdressing was carried out by deep lateral fertilization. In the second node stage of soybeans, avermectin and high-efficiency cyfluthrin were applied for pest and disease control. In the flowering and pod stage, avermectin, high-efficiency cyfluthrin, Bacillus thuringiensis and polythrin were applied. Soybeans were harvested in mid-August.

[0010] S3. In mid-August, the seedlings that have been cultivated for 20-25 days are transplanted from the nursery to the rice field. The row spacing during the transplanting process is 30 cm, the plant spacing is 13.3 cm, and the number of seedlings per stalk is two. A rice transplanting and side deep fertilization machine is used. Base fertilizer is applied to one side of the seedlings by side deep fertilization during transplanting. After transplanting, a shallow water layer of 2-3 cm is maintained to protect the seedlings and promote the growth of the seedlings.

[0011] S4. After the rice turns green 7 days after transplanting, irrigate the field to maintain a 3-5 cm water layer, apply rice tillering fertilizer, spread 3 kg nitrogen fertilizer per mu, and mix benzylsulfuron-methyl into the fertilizer to control weeds in the rice field; drain and dry the field after the rice reaches the peak tillering period to control ineffective tillering;

[0012] Topdressing before rice ear formation: during the rice ear differentiation period, apply rice ear fertilizer, spread 3kg nitrogen fertilizer and 2.14kg potassium fertilizer per mu; 8cm deep water can be irrigated before topdressing to maintain water retention in the field, which is conducive to rice filling. After rice filling, dry-wet alternation irrigation can be used;

[0013] S5. During the rice seedling period, tebuconazole, avermectin and pymetrozine were applied; during the rice cracking period, jinggangmycin, kasugamycin, avermectin and high-efficiency cyfluthrin were applied; in early November, the rice was harvested with low pile retention;

[0014] S6. In early November, 35-40-day-old rapeseed seedlings were transplanted into the rapeseed field with a row spacing of 35-40 cm and a plant spacing of 20-23 cm, with one seedling per hole; while transplanting, basal fertilizer was applied using the side deep fertilization method;

[0015] S7. Topdressing during the rapeseed seedling stage. 9 days after transplanting, apply fertilizer for greening and growth. Apply 2.80 kg of nitrogen fertilizer per mu. Spray boron fertilizer 2-3 times during the rapeseed seedling stage, stalk stage, and before initial flowering. Use 3 packs of Sulebor per mu each time. Add 1 bucket of water to each pack of Sulebor and spray on the leaves.

[0016] Thinning and topdressing of rapeseed seedlings. Generally, the seedlings are thinned twice in the seedbed. The first time is when the cotyledons are flat. The second time is when the first true leaf appears. It is required that the leaves are not overlapping, and the seedlings are not close to each other. The seedlings are evenly dense and thinned. According to the seedling conditions, when the rapeseed seedlings have 3 leaves and 1 heart, paclobutrazol is diluted with water and sprayed evenly, with a dosage of 30g per mu.

[0017] S8. Apply cypermethrin, thiamethoxam and ethotripsy during the seedling stage; apply fluazifop-butyl, chloranil and fucymidone during the bud stage; harvest the rapeseed in late April of the following year and start a new round of soybean, rice and rapeseed rotation.

[0018] Furthermore, in step S2, the topdressing position is 10-12 cm deep between the two rows; 1.86 kg of nitrogen fertilizer and 1.50 kg of potassium fertilizer are applied per mu during the topdressing.

[0019] Furthermore, in step S3, the topdressing position is 5-8 cm deep between the two rows; when topdressing, 10.00 kg of nitrogen fertilizer, 2.84 kg of potassium fertilizer, and 11.41 kg of phosphorus fertilizer are applied per mu as base fertilizer.

[0020] Further, in step S6, the topdressing position is 8-10 cm deep between the two rows; the application rule of base fertilizer is: 6.00 kg of nitrogen fertilizer, 3.44 kg of phosphorus fertilizer, 1.20 kg of potassium fertilizer, and 0.75 kg of borax per mu.

[0021] Furthermore, the cultivation of rice seedlings is carried out as follows: in late July, the rice seeds are soaked in warm water at about 40°C until they turn white, and then the seeds are kept warm for germination. When the buds are about 1 cm long, they are sown. The seed amount is about 3.5 kg per mu for conventional seeds and about 1.5 kg for hybrid seeds. For rice sowing and seedling raising, the soaked rice seeds are sown in the pre-prepared nursery field to cultivate seedlings. The width of the nursery bed in the nursery field is about 1.5 m, and the depth of the nursery bed furrow is 25 cm.

[0022] Furthermore, in late September, rapeseed seeds are sown 35 days before rice harvest, and the rapeseed is sown in the pre-prepared seedbed with a bed width of 1.4-1.6m, a ditch width of 25-30cm, a side ditch depth of 20-25cm, and a middle ditch depth of 15-20cm, which is conducive to draining water; the ratio of field area to seedbed area is 1:(0.1-0.12), that is, 100 mu of rapeseed prepares 10-12 mu of seedbed; when sowing, seeds and urea are mixed at a weight ratio of 1:4 and then sown. After sowing, 100 grams of carbendazim diluted with 30 kilograms of water per mu of seedbed is evenly sprayed to prevent diseases.

[0023] The beneficial effects of the present invention are:

[0024] 1. The crop rotation method provided by the present invention not only breaks the single rice continuous cropping pattern by continuously planting soybeans, rice and rapeseed on the same land in the same year (within 12 months), but also can utilize the extension of the root system of soybeans and rapeseed during their growth, improve soil structure, alleviate soil compaction problems, enhance soil permeability and water retention, and provide an excellent growth environment for subsequent crops; in addition, crop rotation helps to restore microbial activity in the soil, improve soil fertility, and thus promote the high-yield stability of crops, increase the comprehensive yield of rice, soybeans and rapeseed, and have higher economic benefits.

[0025] 2. The crop rotation method provided by the present invention regulates the local nutrients in the rhizosphere by adopting the side deep fertilization technology, so as to accurately apply fertilizer to a specific depth near the root system according to the differences in rooting depths and nutrient requirements of different crops during their growth, thereby increasing the nutrient concentration around the crop root system, thereby significantly improving the fertilizer utilization rate and crop absorption efficiency. The above fertilization method not only reduces the use of chemical fertilizers and environmental pollution, but also improves the soil nutrient retention capacity, reduces soil nutrient loss, and enables soil health and productivity to be maintained for a long time; at the same time, side deep fertilization can be carried out simultaneously with sowing, which simplifies the operation process and improves production efficiency; in addition, in the crop rotation system, the application of side deep fertilization is closely combined with the growth characteristics of soybeans, rice, and rapeseed, thereby achieving the goals of increasing production and efficiency, saving costs and protecting the environment.

[0026] 3. The crop rotation method provided by the present invention, through the annual crop rotation of rice, soybeans and rapeseed, optimizes the planting pattern of soybeans in the rice rotation system (i.e., the pattern of planting soybeans after harvesting rice), fully utilizes the natural resource advantages of the middle and lower reaches of the Yangtze River, and significantly increases the yield of soybeans while ensuring the stable production of rice. The introduction of the crop rotation system provides a more suitable growth environment for soybeans, effectively prolongs the growth cycle of soybeans, and ensures the stability of its yield; in addition, the technology relies on full mechanized operations, simplifies the planting and management process of soybeans, reduces labor costs, and further improves production efficiency.

[0027] 4. The crop rotation method provided by the present invention uses soybeans as the previous crop of rice, and can use the unique biological nitrogen fixation of soybeans to fix the nitrogen element in the atmosphere, providing part of the nitrogen nutrition for the subsequent rice. This process effectively reduces the use of nitrogen fertilizers in the rice planting process, reduces the planting cost, and effectively reduces the negative impact of nitrogen fertilizers on the soil and the environment; by introducing the rotation system of spring soybeans-late rice-rapeseed, the natural climate conditions of the four seasons of the year are fully utilized, the plant coverage of the whole year is guaranteed, and the utilization rate of the land is maximized. Through the plant coverage of the whole year, not only the continuous and efficient utilization of land resources is achieved, but also the frequency of weeds and pests is reduced, thereby reducing the use of pesticides and further achieving the goal of green agriculture. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 This article provides the key growth periods of soybean, rice and rapeseed in the spring soybean-late rice-rapeseed annual rotation system, as well as brief cultivation and management information. DETAILED DESCRIPTION

[0029] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0030] It should also be noted that, in order to avoid obscuring the present invention due to unnecessary details, only structures and / or processing steps closely related to the scheme of the present invention are shown in the drawings, while other details that are not closely related to the present invention are omitted.

[0031] In addition, it should be noted that the terms "comprises", "includes" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or apparatus that includes a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or apparatus.

[0032] See also Figure 1 As shown, the annual crop rotation method of soybean, rice and rapeseed provided by the present invention is applicable to the middle and lower reaches of the Yangtze River, and comprises the following steps:

[0033] S1. Soybean planting: plough and level the land in advance, with a tillage depth of 22-25cm, plow the whole field and form ridges with a ridge width of 1.2-1.8m; sow soybeans in early May, direct sowing, sowing in holes, with a hole spacing of 10-13cm, a row spacing of 40-43cm, 2-3 seeds per hole, 7-9kg of seeds per mu, and a sowing depth of 3-5cm; after sowing, 140g of isothiocarb and 180g of glyphosate are mixed and diluted with 60kg of water and sprayed for closed weeding;

[0034] S2. Field management and harvesting: 2-3 inter-row cultivation is performed before closing the soybean rows (when the leaves of the soybean plants completely cover the ground, forming a continuous green cover layer) to remove weeds and loosen the soil, which can enhance root development and plant resistance. Inter-row cultivation and weeding should be performed regularly throughout the soybean growth period;

[0035] During the second node of soybeans, use a side deep fertilizer machine to apply topdressing at a depth of 10-12cm between the two rows, and apply 1.86kg of nitrogen fertilizer (with urea as the fertilizer source) and 1.50kg of potassium fertilizer (with potassium chloride as the fertilizer source) per mu as topdressing to promote the growth of strong stalks and branches of soybeans and enhance their resistance to lodging; during the soybean pod and grain filling stage, spread 0.93kg of nitrogen fertilizer per mu as topdressing to promote the full growth of pods and improve yield and quality;

[0036] In the second node stage of soybean, 10 ml of avermectin and 60 ml of high-efficiency flucythrinate were mixed and then diluted with 60 kg of water for spraying to control pests and diseases. In the flowering and pod stage, 10 ml of avermectin, 60 ml of high-efficiency flucythrinate, 200 ml of Bacillus thuringiensis and 10 ml of polyphenthrin were mixed and then diluted with 60 kg of water for spraying to strengthen pest and disease control and reduce insect-infested pods and diseased spotted pods. In mid-August, soybeans were harvested mechanically. After harvesting, the soybean kernels were dried to the storage moisture content and stored properly, and the soybean straw was removed from the field.

[0037] S3, rice planting: After the soybean-planted field is irrigated and soaked for 1 day, a rotary tiller is used to plow the field to a depth of 20-25 cm, and a harrow is used to level the rice field, maintaining a 1 cm shallow water layer; in mid-August, the seedlings cultivated for 20-25 days are transplanted from the nursery field to the rice field, with a row spacing of 30 cm and a plant spacing of 13.3 cm during the transplanting process, and two seedlings per plant; a rice transplanting and side deep fertilization integrated machine is used, and base fertilizer is applied at a depth of 5-8 cm on one side of the seedlings during transplanting, that is, 10.00 kg of nitrogen fertilizer, 2.84 kg of potassium fertilizer, and 11.41 kg of phosphate fertilizer (with superphosphate as fertilizer source) are applied per mu as base fertilizer, and a 2-3 cm shallow water layer is maintained after transplanting to protect the seedlings and promote the growth of the seedlings;

[0038] S4. Fertilization: 7 days after the rice is transplanted and turns green, irrigate the field to maintain a 3-5 cm water layer, apply rice tillering fertilizer, that is, spread 3 kg of nitrogen fertilizer per mu, and mix 80 g of benzylsulfuron-methyl into the fertilizer to control weeds in the rice field; drain and dry the field after the rice reaches the peak tillering period to control ineffective tillering;

[0039] Topdressing before rice earing: During the rice ear differentiation period (when 80% of the stems in the field reach this period, white hairs can be seen inside the rice stems after peeling them open), apply rice ear fertilizer, spreading 3kg of nitrogen fertilizer and 2.14kg of potassium fertilizer per mu; 8cm deep water can be irrigated before topdressing to keep the field water-retaining, which is conducive to rice filling. After rice filling, a combination of shallow water irrigation and natural drying can be used for irrigation, with a dry-wet alternation method. The depth of each irrigation is 3-5cm. After the surface water layer disappears, irrigate again 5-7 days later to reduce the risk of lodging;

[0040] S5. Pest and disease control and harvesting: During the rice seedling period, 10 ml of tebuconazole, 10 ml of avermectin and 8 g of pymetrozine were mixed and then diluted with 60 kg of water for spraying for pest and disease control; during the rice cracking period, 35 g of Jinggangmycin, 40 ml of kasugamycin, 10 ml of avermectin and 40 ml of high-efficiency flucythrin were mixed and then diluted with 60 kg of water for spraying for sheath blight, rice blast and rice planthoppers to ensure that the rice cracking period passes smoothly;

[0041] In early November, rice is harvested with harvesting machinery at a height of 5-8 cm. The rice is properly stored after being dried to the storage moisture content, and the rice straw is removed from the field.

[0042] S6. Rapeseed planting: After rice harvest, use a tiller to plow the rapeseed field and break up the soil. After plowing, dig trenches with a width of 1.8-2m, a trench width of 25-30cm, a side trench depth of 20-25cm, and a middle trench depth of 15-20cm;

[0043] In early November, 35-40-day-old rapeseed seedlings were transplanted into the rapeseed field with a row spacing of 35-40cm and a plant spacing of 20-25cm, with one seedling per hole. At the same time, a side deep fertilizer machine was used to apply basal fertilizer at a depth of 8-10cm between the two rows, with 6.00kg of nitrogen fertilizer, 3.44kg of phosphorus fertilizer, 1.20kg of potassium fertilizer, and 0.75kg of borax per mu as basal fertilizer;

[0044] S7. Topdressing of rapeseed: Topdressing of rapeseed in seedling stage, 9 days after transplanting, apply fertilizer for greening and growth, that is, spread 2.80kg of nitrogen fertilizer per mu; spray boron fertilizer 2-3 times in rapeseed seedling stage, stalk stage, and before initial flowering, each time use 3 bags of Sulebor per mu, and each bag of Sulebor is diluted with 30kg of water and sprayed on the leaves;

[0045] Rape seedling thinning (refers to selectively removing some overcrowded seedlings after the rape seedlings grow to a certain height to reduce competition between seedlings and ensure that each plant has enough growth space and resources) and topdressing. Generally, the seedlings are thinned twice in the seedbed. The first time is when the cotyledons are flat; the second time is when the first true leaf appears. It is required that leaves do not overlap leaves, seedlings do not lean against seedlings, and dense and thinning are supplemented; according to the seedling conditions, when the rape seedlings have 3 leaves and 1 heart, paclobutrazol is evenly sprayed with water, with a dosage of 30g per mu, to promote root growth and cultivate strong seedlings;

[0046] S8. Pest and disease control and harvesting: In the seedling stage, use 8ml of cypermethrin, 15ml of thiamethoxam and 5ml of ethopropenol mixed with 60kg of water for spraying for pest and disease control; in the bud stage, in addition to basic control, apply 20ml of fluazifop-hydroxyamide and 50ml of scutellaria baicalensis mixed with 60kg of water per mu to spray on the base of rapeseed stems to control sclerotinia disease; in late April of the following year, when 90-95% of the siliques of rapeseed are mature, use a combine harvester to harvest and start a new round of soybean, rice and rapeseed rotation.

[0047] As an embodiment of the present invention, soybeans need to be dressed before sowing, and the dressing is performed as follows: select full and intact soybeans as seeds, mix the soybean seeds with a seed dressing agent evenly, perform the first seed dressing, and after the seed dressing is completed, dry the seeds in a cool and ventilated place, and the seeds can be stored for up to 30 days; wait at least 24 hours after the first seed dressing, and perform the second seed dressing. To ensure that the effect of the seed dressing agent is better exerted, the seeds after the second seed dressing need to be sown within 1-3 days and avoid wind and sun. The seed dressing agent for the first seed dressing is thiamethoxam, and the seed dressing agent for the second seed dressing is soybean rhizobium agent.

[0048] As an embodiment of the present invention, before sowing soybeans, a rotary tillage machine is used to plow and level the land, with a tillage depth of 20-25 cm, and the whole field is plowed and ridged, with a ridge width of 1.2-1.8 m. This step improves soil conditions to provide a suitable growth environment for soybeans.

[0049] As an embodiment of the present invention, the cultivation of rice seedlings is carried out as follows: in late July, the rice seeds are soaked in warm water at about 40°C until they turn white, and then the seeds are kept warm and germinated. When the buds are about 1 cm long, they are sown, and the seed amount is about 3.5 kg per mu for conventional seeds and about 1.5 kg for hybrid seeds; rice seeding and seedling raising, the soaked rice seeds are sown in a pre-prepared nursery field to cultivate seedlings, the seedling bed width of the nursery field is about 1.5 m, and the seedling bed furrow depth is 25 cm. Attention should be paid to water management during the seedling raising process to ensure the healthy growth of the seedlings.

[0050] As an embodiment of the present invention, the cultivation of rapeseed seedlings is carried out as follows: in late September, rapeseed seeds are sown 35 days before rice harvest, and the rapeseed is sown in a pre-prepared seedling bed with a ridge width of 1.4m, a ditch width of 25-30cm, a side ditch depth of 20-25cm, and a middle ditch depth of 25-20cm, which is conducive to draining water; the ratio of field area to seedling bed area is 1:(0.1-0.12), that is, 100 mu of rapeseed prepares 10-12 mu of seedling bed; when sowing, the seeds and urea are mixed at a weight ratio of 1:4 and then sown. After sowing, 100 grams of carbendazim diluted with 30 kilograms of water per mu of seedling bed is evenly sprayed to prevent diseases.

[0051] The annual crop rotation method of soybean, rice and rapeseed proposed by the present invention is further described below in conjunction with specific embodiments:

[0052] Example 1

[0053] In this embodiment, the annual rotation method of soybean, rice and rapeseed proposed by the present invention is applied to Xiaogan City, Hubei Province. In Examples 1-3, Zhongdou 68 is used as the mid-spring soybean, Taiyou 398 is used as the late rice variety, and Huayouza 62R is used as the rapeseed variety.

[0054] Specifically, the crop rotation method includes the following steps:

[0055] S1. Select full and intact spring soybeans as seeds, mix the soybean seeds with thiamethoxam seed dressing agent evenly, and dry the seeds in a cool and ventilated place after seed dressing. The seeds can be stored for up to 30 days. Wait at least 24 hours after seed dressing, and then mix the seeds with soybean rhizobium agent. To ensure that the seed dressing agent plays a better role, the seeds after seed dressing need to be sown within 1-3 days and avoid wind and sun exposure;

[0056] The land was plowed and leveled in advance, with a tillage depth of 25 cm, and the whole field was plowed and ridged, with a ridge width of 120 cm; soybeans were sown on May 3rd, with direct sowing, sowing in holes, with a hole spacing of 10 cm and a row spacing of 40 cm. Two seeds were sown in each hole, with a seed rate of 7.5 kg per mu and a sowing depth of 3 cm; after sowing, 140 g of isothiocyanate and 180 g of glyphosate were mixed and diluted with 60 kg of water and sprayed for closed weeding;

[0057] S2. Carry out 2-3 intertillage before closing the soybean row, which can remove weeds and loosen the soil, enhance root development and plant resistance, and carry out intertillage and weeding regularly throughout the soybean growth period;

[0058] During the second node of soybeans, use a side deep fertilizer machine to apply topdressing fertilizer at a depth of 10 cm between the two rows, and apply 1.86 kg of nitrogen fertilizer and 1.50 kg of potassium fertilizer per mu as topdressing fertilizer to promote the growth of strong stalks and branches of soybeans and enhance their resistance to lodging; during the soybean pod and grain filling stage, spread 0.93 kg of nitrogen fertilizer per mu as topdressing fertilizer to promote the full growth of pods and improve yield and quality;

[0059] Apply avermectin and high-efficiency cyfluthrin to control pests and diseases during the second node of soybeans, and apply avermectin, high-efficiency cyfluthrin, Bacillus thuringiensis and polythrin during the flowering and pod stage to strengthen pest and disease control and reduce insect-infested pods and disease-spotted pods; harvest soybeans mechanically in mid-August, and dry the soybeans to the storage moisture content after harvesting and store them properly;

[0060] S3. In late July, soak the rice seeds in warm water at about 40°C until they turn white, and then keep warm to germinate. Sow when the buds are about 1 cm long. The seed amount is about 3.5 kg per mu for conventional seeds and about 1.5 kg for hybrid seeds. Sow and raise rice seedlings. Sow the soaked rice seeds in the seedling field that has been prepared in advance to cultivate seedlings. The seedling bed width of the seedling field is about 1.5m, and the seedling bed furrow depth is 25cm. Attention should be paid to water management during the seedling raising process to ensure the healthy growth of the seedlings.

[0061] After the soybean-planted fields were irrigated and soaked for 1 day, a rotary tiller was used to till the fields to a depth of 25 cm, and a harrow was used to level the rice fields, maintaining a 1 cm shallow water layer; in mid-August, the rice seedlings that had been cultivated for 24 days were transplanted from the nursery fields to the rice fields, with a row spacing of 30 cm and a plant spacing of 13.3 cm during the transplanting process, and two seedlings per plant; a rice transplanting and side deep fertilization integrated machine was used to apply base fertilizer at a depth of 5 cm on one side of the seedlings during transplanting, with 10.00 kg of nitrogen fertilizer, 2.84 kg of potassium fertilizer, and 11.41 kg of phosphorus fertilizer applied per mu as base fertilizer, and a 2-3 cm shallow water layer was maintained after transplanting to protect the seedlings and promote their growth;

[0062] S4. After the rice turns green 7 days after transplanting, irrigate the field to maintain a 3-5 cm water layer, apply rice tillering fertilizer, spread 3 kg nitrogen fertilizer per mu, and mix benzylsulfuron-methyl into the fertilizer to control weeds in the rice field; drain and dry the field after the rice reaches the peak tillering period to control ineffective tillering;

[0063] Topdressing before rice panicle formation: Apply rice panicle fertilizer during the rice panicle differentiation period, spreading 3kg nitrogen fertilizer and 2.14kg potassium fertilizer per mu; 8cm deep water can be irrigated before topdressing to maintain water retention in the field, which is conducive to rice filling. After rice filling, dry-wet alternating irrigation can be used to reduce the risk of lodging;

[0064] S5. During the rice seedling period, tebuconazole, avermectin and pymetrozine were used for pest and disease control;

[0065] Pest and disease control during the rice cracking period: Use jinggangmycin, kasugamycin, avermectin and high-efficiency flucythrinate to control diseases and pests such as sheath blight, rice blast and rice planthoppers during the rice cracking period to ensure that the rice cracking period passes smoothly; use harvesting machinery to harvest rice with low piles in early November, and store it properly after drying it to the storage moisture content;

[0066] S6. In late September, rapeseed seeds were sown 35 days before rice harvest. The rapeseed was sown in the seedbed that had been prepared in advance. The width of the ridge was 1.4m, the width of the ditch was 30cm, the depth of the side ditch was 25cm, and the depth of the middle ditch was 20cm, which was conducive to draining water. The ratio of the field area to the seedbed area was 1:(0.1-0.12), that is, 100 mu of rapeseed was prepared for 10-12 mu of seedbed area. When sowing, the seeds and urea were mixed at a weight ratio of 1:4 and then sown. After sowing, 100g of carbendazim diluted with 30kg of water was evenly sprayed on each mu of seedbed to prevent diseases.

[0067] After rice harvest, use a tiller to plow the rapeseed field and break up the soil. After plowing, dig trenches with a width of 2m, a width of 30cm, a side trench depth of 25cm, and a middle trench depth of 20cm.

[0068] In early November, 35-day-old rapeseed seedlings were transplanted into the rapeseed field with a row spacing of 40 cm and a plant spacing of 20 cm, with one seedling per hole. At the same time, a side deep fertilizer machine was used to apply basal fertilizer at a depth of 8 cm between the two rows. 6.00 kg of nitrogen fertilizer, 3.44 kg of phosphorus fertilizer, 1.20 kg of potassium fertilizer, and 0.75 kg of borax were applied per mu as basal fertilizer.

[0069] S7. Topdressing during the rapeseed seedling stage. 9 days after transplanting, apply fertilizer for greening and growth of plants, and spread 2.80 kg of nitrogen fertilizer per mu. During the rapeseed seedling stage, stalk stage, and before initial flowering, spray boron fertilizer three times, using 3 packets of Sulebor per mu each time, and each packet of Sulebor was diluted with 1 bucket of water for foliar spraying.

[0070] Thinning and topdressing of rapeseed seedlings. Generally, the seedling bed is thinned twice. The first time is when the cotyledons are flat. The second time is when the first true leaf appears. It is required that the leaves do not overlap with each other and the seedlings do not lean against each other. The seedlings are evenly dense and thinned. According to the seedling conditions, when the rapeseed seedlings have 3 leaves and 1 heart, paclobutrazol is evenly sprayed with water, with a dosage of 30g per mu, to promote root growth and cultivate strong seedlings.

[0071] S8. Use cypermethrin, thiamethoxam and ethotripsy for disease and pest control during the seedling stage. In addition to basic control during the bud stage, apply fluazifop-butyl, chloranil and fucymidone to spray the base of the rapeseed stem to control sclerotinia disease. In late April of the following year, use a combine harvester to harvest when 90-95% of the siliques of the rapeseed are mature.

[0072] Furthermore, in order to select the best soybean variety suitable for rice field planting during crop rotation, the crop rotation results of Zhongdou 68, Zhongdou 52 and Edou 10 were compared, and the results are shown in Table 1; in addition, the growth periods of Zhongdou 52, Zhongdou 68 and Edou 10 are 106 days, 92 days and 99 days, respectively. Considering the above factors, Zhongdou 68 was selected as the best soybean variety for crop rotation.

[0073] Table 1 Yield of different soybean varieties planted as spring soybeans

[0074]

[0075] Example 1 The yield and fertilizer utilization rate of each crop are shown in Table 2. In the table, rice yield equivalent = (yield of the crop * energy content per unit weight of the crop seed) / energy content per unit weight of rice seed. Among them, the energy content per unit weight of rice, soybean and rapeseed seeds are 14.7, 23.7 and 27.6 MJ / kg respectively.

[0076] Table 2 Yield and fertilizer utilization rate of each crop in Example 1

[0077]

[0078] Comparative Example 1

[0079] The only difference between Comparative Example 1 and Example 1 is that when applying topdressing to soybeans, rice and rapeseed, the side deep fertilization method is not adopted, but the topdressing is carried out in a conventional manner, that is, fertilizing the roots of soybean and rapeseed plants and directly spreading the fertilizer in the rice field. The weight of the fertilizer used for topdressing in this step is the same as that in Example 1, and the other steps and parameters are the same as those in Example 1, which will not be repeated here.

[0080] Comparative Example 2

[0081] The only difference between Comparative Example 2 and Example 1 is that rapeseed is not planted during the crop rotation process, that is, after the rice is harvested, the field is idle in winter and soybeans are directly planted in the spring of the second year. The other steps and parameters are the same as those in Example 1 and will not be repeated here.

[0082] Comparative Example 3

[0083] The only difference between Comparative Example 3 and Example 1 is that soybeans are not planted during the crop rotation process, that is, rice is planted directly after rapeseed is harvested. Other steps and parameters are the same as those in Example 1 and will not be repeated here.

[0084] The yields of the crops in Example 1 and Comparative Examples 1-3 are shown in Table 3, where rice yield equivalent = (yield of the crop * energy content per unit weight of the crop grain) / energy content per unit weight of rice grain. Among them, the energy content per unit weight of rice, soybean and rapeseed grains are 14.7, 23.7 and 27.6 MJ / kg, respectively.

[0085] Table 3 Yield of each crop in Example 1 and Comparative Examples 1-3

[0086]

[0087]

[0088] The above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solution of the present invention.

Claims

1. A method for annual crop rotation of soybean, rice and rapeseed, characterized in that: The method is applicable to the middle and lower reaches of the Yangtze River, and comprises the following steps: S1. Sow soybeans in early May. The sowing method is direct seeding. Sow in holes with a hole spacing of 10-13 cm and a row spacing of 40-43 cm. Sow 2-3 seeds per hole. The seed rate is 7-9 kg per mu and the sowing depth is 3-5 cm. After sowing, use a mixture of isothiocarb and glyphosate for closed weeding. S2. 2-3 inter-row cultivations were carried out before closing the soybean rows. In the second node stage of soybeans, topdressing was carried out by deep lateral fertilization. In the second node stage of soybeans, avermectin and high-efficiency cyfluthrin were applied for pest and disease control. In the flowering and pod stage, avermectin, high-efficiency cyfluthrin, Bacillus thuringiensis and polythrin were applied. Soybeans were harvested in mid-August. S3. In mid-August, the seedlings that have been cultivated for 20-25 days are transplanted from the nursery to the rice field. The row spacing during the transplanting process is 30 cm, the plant spacing is 13.3 cm, and the number of seedlings per stalk is two. A rice transplanting and side deep fertilization machine is used. Base fertilizer is applied to one side of the seedlings by side deep fertilization during transplanting. After transplanting, a shallow water layer of 2-3 cm is maintained to protect the seedlings and promote the growth of the seedlings. S4. After the rice turns green 7 days after transplanting, irrigate the field to maintain a 3-5 cm water layer, apply rice tillering fertilizer, spread 3 kg nitrogen fertilizer per mu, and mix benzylsulfuron-methyl into the fertilizer to control weeds in the rice field; drain and dry the field after the rice reaches the peak tillering period to control ineffective tillering; Topdressing before rice ear formation: during the rice ear differentiation period, apply rice ear fertilizer, that is, spread 3kg nitrogen fertilizer and 2.14kg potassium fertilizer per mu; 8cm deep water can be irrigated before topdressing to maintain water retention in the field, which is conducive to rice filling. After the rice filling is completed, the dry-wet alternation method can be used for irrigation; S5, during the rice seedling period, tebuconazole, avermectin and pymetrozine were applied; During the rice rupture period, Jinggangmycin, Kasugamycin, Avermectin and High-efficiency Cypermethrin were applied; the rice was harvested with low pile retention in early November; S6. In early November, 35-40-day-old rapeseed seedlings were transplanted into the rapeseed field with a row spacing of 35-40 cm and a plant spacing of 20-23 cm, with one seedling per hole; while transplanting, basal fertilizer was applied using the side deep fertilization method; S7. Topdressing during the rapeseed seedling stage. 9 days after transplanting, apply fertilizer for greening and growth, that is, spread 2.80kg of nitrogen fertilizer per mu; spray boron fertilizer 2-3 times during the rapeseed seedling stage, stalk stage, and before initial flowering. Use 3 bags of Sulebor per mu each time, and mix each bag of Sulebor with 1 bucket of water for foliar spraying; Thinning and topdressing of rapeseed seedlings. Generally, the seedlings are thinned twice in the seedbed. The first time is when the cotyledons are flat. The second time is when the first true leaf appears. It is required that the leaves are not overlapping, and the seedlings are not close to each other. The seedlings are evenly dense and thinned. According to the seedling conditions, when the rapeseed seedlings have 3 leaves and 1 heart, paclobutrazol is diluted with water and sprayed evenly, with a dosage of 30g per mu. S8. Apply cypermethrin, thiamethoxam and ethotripsy during the seedling stage; apply fluazifop-butyl, chloranil and fucymidone during the bud stage; harvest the rapeseed in late April of the following year and start a new round of soybean, rice and rapeseed rotation.

2. The crop rotation method according to claim 1, characterized in that: In step S2, the topdressing position is 10-12 cm deep between the two rows; 1.86 kg of nitrogen fertilizer and 1.50 kg of potassium fertilizer are applied per mu.

3. The crop rotation method according to claim 1, characterized in that: In step S3, the topdressing position is 5-8 cm deep between the two rows; when topdressing, 10.00 kg of nitrogen fertilizer, 2.84 kg of potassium fertilizer, and 11.41 kg of phosphorus fertilizer are applied per mu as base fertilizer.

4. The crop rotation method according to claim 1, characterized in that: In step S6, the topdressing position is 8-10 cm deep between the two rows; the application rule of base fertilizer is: 6.00 kg of nitrogen fertilizer, 3.44 kg of phosphorus fertilizer, 1.20 kg of potash fertilizer, and 0.75 kg of borax per mu.

5. The crop rotation method according to claim 1, characterized in that: The cultivation of rice seedlings is carried out as follows: in late July, the rice seeds are soaked in warm water at about 40°C until they turn white, and then they are kept warm for germination. They are sown when the buds are about 1 cm long. The seed rate is about 3.5 kg per mu for conventional seeds and about 1.5 kg for hybrid seeds. For rice sowing and seedling raising, the soaked rice seeds are sown in the nursery field that has been prepared in advance to cultivate seedlings. The width of the nursery bed in the nursery field is about 1.5 m, and the depth of the nursery bed furrow is 25 cm.

6. The crop rotation method according to claim 1, characterized in that: In late September, rapeseed seeds are sown 35 days before rice harvest. The rapeseed is sown in the pre-prepared seedbed with a bed width of 1.4-1.6m, a ditch width of 25-30cm, a side ditch depth of 20-25cm, and a middle ditch depth of 15-20cm to facilitate drainage of waterlogging. The ratio of field area to seedbed area is 1:(0.1-0.12), that is, 100 mu of rapeseed prepares 10-12 mu of seedbed. When sowing, seeds and urea are mixed at a weight ratio of 1:4 and then sown. After sowing, 100 grams of carbendazim diluted with 30 kilograms of water per mu of seedbed is evenly sprayed to prevent diseases.

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