Grain and feed dual-purpose corn cultivation method

Abstract

The invention discloses a method for cultivating grain-feed corn, which comprises the following steps of: selecting a grain corn variety, selecting a land and preparing the land; the method comprises the following steps: selecting corn seeds, ridging and earthing, performing single-grain precision seeding in a suitable seeding period from May 5th to May 15th, and seeding selected conventional high-grain-yield corn varieties according to the density which is increased by 5-10% compared with the recommended density of pure grains; applying a base fertilizer and a silicon-calcium-magnesium compound fertilizer at the stem position before the jointing stage, and applying a nitrogen fertilizer and a silicon-calcium fertilizer in the large bell mouth stage; green-keeping and grain-increasing fertilizer is applied 10-15 days after spinning, wherein the green-keeping and grain-increasing fertilizer comprises potash fertilizer, urea and phosphate fertilizer; from the final stage of wax ripening to the initial stage of complete ripening, when milk lines of the grains disappear or black layers are formed, the grains are harvested, and the stem and leaf structures of plants which are not completely dried up are kept to be complete; topdressing nitrogen fertilizer after harvesting, spraying growth hormone to induce differentiation of stem base regeneration buds, and harvesting the stem bases after the stem base regeneration buds grow and turn green; according to the method, the plant stem base regeneration buds are induced to differentiate, turn green and grow again, so that secondary growth and utilization of the corn straws are realized.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of crop cultivation, in particular to a kind of grain and forage dual-purpose corn cultivation method. BACKGROUND

[0002] "Grain and forage dual-purpose corn cultivation" refers to a way of planting a specific variety of corn, which aims to harvest corn kernels as grain (cereal) and effectively utilize its stem, leaf, bract and other nutrient body parts as high-quality silage feed (or green feed) in the same season planting of the same corn variety. The corn can maintain good green and moisture during kernel maturation, delaying senescence, which is beneficial to the quality of silage feed (good nutrition and palatability). In short, it is to plant one kind of corn that can be used as both food and livestock feed, achieving "one thing for two uses" or "one place for double harvest".

[0003] The existing conventional corn planting method is difficult to effectively achieve the goal of "grain and forage dual-purpose", mainly due to fundamental differences or conflicts in variety characteristics, cultivation goals, management measures and harvesting methods. Specifically, the breeding goal is centered on high grain yield, pursuing fullness of grain, starch content, resistance to lodging, and fast dehydration. Such varieties often have shorter plants, relatively early leaf senescence, lower biomass, and high lignification degree of stem and stalk in later stages, low nutritional value and poor palatability, which are not suitable for high-quality silage feed. The silage special corn is bred with the goal of maximizing whole-plant biomass and nutritional value, with tall and lush plants, good green retention, relatively low grain yield, and possibly lower grain quality than grain varieties.

[0004] Therefore, it is necessary to design a grain and forage dual-purpose corn cultivation method to solve the above problems. SUMMARY

[0005] The present application overcomes the shortcomings of the prior art and provides a grain and forage dual-purpose corn cultivation method.

[0006] To achieve the above-mentioned purpose, the technical scheme adopted by the present application is as follows: a grain and forage dual-purpose corn cultivation method, comprising the following steps:

[0007] Step S1, selecting grain corn varieties, selecting land and preparing the land;

[0008] Step S2, ridging and covering soil, during the suitable sowing period from May 5th to 15th, single-precision sowing is carried out, and the selected conventional high-yield grain corn variety is sown at a density of 5-10% higher than the recommended density of pure grain;

[0009] Step S3, applying base fertilizer and silicon-calcium-magnesium compound fertilizer at the stem position before the jointing stage, and implementing nitrogen fertilizer and silicon-calcium fertilizer at the large trumpet stage;

[0010] Step S4, 10-15 days after spinning, a green-keeping and kernel-increasing fertilizer is applied, wherein the green-keeping and kernel-increasing fertilizer comprises potassium fertilizer, urea and phosphorus fertilizer;

[0011] Step S5, at the end of the milking stage to the beginning of the ripening stage, the grains are harvested when the milk line disappears or the black layer is formed, and the plant stem and leaf structure that has not completely dried are kept intact;

[0012] Step S6, after harvesting, nitrogen fertilizer is applied and growth hormone is sprayed to induce the differentiation of the stem base into new buds, and the stem base is harvested after the new buds grow back.

[0013] In a preferred embodiment of the present application, in the step S1,

[0014] Optionally, loam soil or sandy loam soil with convenient irrigation, convenient management, pH between 5.8-7, and medium or above fertility is selected.

[0015] Land preparation: after the land is selected, the land is mechanically rotary plowed to a depth of 20-25 nm, and a drainage ditch is dug.

[0016] In a preferred embodiment of the present application, in the step S2, the ridging and soil covering adopts a ridging planting + ditch compartment drainage mode, which includes a wide row of 75-80 cm, a narrow row of 40-45 cm, a ridge height of 15-20 cm, a ridge top width of ≥25 cm, and a soil covering thickness in the range of 4-6 cm.

[0017] In a preferred embodiment of the present application, in the step S2, the density of the conventional high-yield grain corn variety is in the range of 4500-5500 plants per mu.

[0018] In a preferred embodiment of the present application, in the step S3, the base fertilizer is phosphorus and potassium fertilizer, and the base fertilizer application amount is 20-25 kg per mu, and the silicon, calcium and magnesium compound fertilizer application amount is 30-40 kg per mu.

[0019] In a preferred embodiment of the present application, the nitrogen fertilizer is urea, and in the step S3, the nitrogen fertilizer application amount is 20-22 kg per mu, the silicon and calcium fertilizer application amount is 10-15 kg per mu in the row, and the silicon and calcium fertilizer is deeply applied and covered with soil, wherein the effective SiO2 in the silicon and calcium fertilizer is ≥25%.

[0020] In a preferred embodiment of the present application, in the step S4, the green-keeping and kernel-increasing fertilizer comprises potassium fertilizer, urea and phosphorus fertilizer.

[0021] The composition ratio between the potassium fertilizer, urea, phosphorus fertilizer and trace elements is 60-70:15-20:5-10, wherein the potassium fertilizer application amount is 10-15 kg per mu, the urea application amount is 3-5 kg per mu, and the phosphorus fertilizer application amount is 1-2 kg per mu.

[0022] In a preferred embodiment of the present application, in the step S6, the nitrogen fertilizer is urea, the urea application amount is 5-10 kg / mu, and potassium sulfate is applied in combination, and the potassium sulfate application amount is 3-5 kg / mu.

[0023] In a preferred embodiment of the present application, in the step S6, the growth hormone includes gibberellin, 6-benzylaminopurine and indole acetic acid; the concentration of gibberellin is 5-10 mg / L, the concentration of 6-benzylaminopurine is 10-20 mg / L, and the concentration of indole acetic acid is 1-2 mg / L.

[0024] The growth hormone is mixed, and 30-40 L / mu is sprayed on the stem base to induce the stem base to differentiate and grow again.

[0025] The present application solves the defects in the background art, and has the following beneficial effects:

[0026] (1) The present application provides a kind of grain and forage dual-purpose corn cultivation method, in the early management in field, by increasing the application of SiO2-rich silicon calcium magnesium compound fertilizer and potassium fertilizer and deep application in row, so that the stem structure of corn is significantly strengthened, the resistance to lodging is improved, silicon element can be deposited in cell wall in corn body, the mechanical strength is enhanced, at the same time, calcium and magnesium elements help cell division and photosynthesis, so as to improve photosynthetic efficiency and biomass accumulation, during which, potassium fertilizer delays plant senescence and enhances stem flexibility, supplemented with appropriate amount of nitrogen to maintain leaf activity, successfully breaking the shackles of traditional grain corn at harvest time, stem and leaf are dry and yellow and cannot be used, so that at the time of corn harvest, the middle and lower stems still have considerable green parts and higher moisture, providing material basis for later green retention and regeneration potential.

[0027] (2) The present application provides a kind of grain and forage dual-purpose corn cultivation method, which uses silicon calcium magnesium compound fertilizer, potassium fertilizer and nitrogen fertilizer to maintain the vitality of corn stem, after the grain is harvested, combined with the application of nitrogen fertilizer and the spraying of growth hormone, the stem base of the plant is induced to differentiate and grow again, so as to realize the secondary growth and utilization of corn straw, and the corn stem and leaf in the dry and aging stage can synthesize chlorophyll again and start photosynthesis, compared with the existing green corn which needs to be specially selected for green retention and has limited grain yield, the present application realizes functional regeneration without changing the variety, provides a later utilization value for conventional grain varieties, and further enhances the economic adaptability of cultivation.

[0028] (3) The application realizes the effect of grain-feeding dual-purpose of grain maize varieties by dynamic management planting of grain maize varieties in the planting process, which can not only make high yield of corn, but also make corn straw can be collected for green feed storage, compared with the waste mode of direct ploughing or discarding straw after corn harvesting in the prior art, the method realizes "reutilization", significantly improves the unit area output rate and economic benefit, and reduces the environmental pollution risk caused by straw burning.

[0029] (4) The application adopts green-preserving and particle-increasing fertilizer topdressing treatment, which significantly delays leaf early senescence, prolongs photosynthesis time, potassium fertilizer promotes directional transportation of carbohydrates from stems and leaves to kernels, delays leaf protein degradation and chlorophyll destruction process, is beneficial to transportation and accumulation of carbohydrates, nitrogen maintains leaf activity, and phosphorus promotes energy metabolism, thereby realizing not only supporting kernel plumping, but also avoiding stems and leaves from withering yellow too early, laying a good physiological foundation for later green return induction, compared with the problems of rapid plant senescence and straw discoloration and dryness in the prior art, the application improves the moisture content and developability of straw at the time of straw harvesting, further improves the palatability and nutritional value of straw as silage, realizes maximum kernel yield, and retains green stems and leaves for subsequent reuse.

[0030] (5) The application adopts wide-narrow row staggered + ridging planting + ditch compartment drainage cultivation structure design mode in the ridging and soil covering stage, which not only optimizes the spatial distribution of corn plant groups, but also improves the ventilation and light transmission between plants and the efficiency of post-rain drainage, by controlling the ridge height and soil covering thickness, the root system is more easily to penetrate the soft soil layer, and the absorption capacity of the root system to elements such as silicon, calcium and magnesium is improved, thereby strengthening the utilization efficiency of water and fertilizer by the plant, compared with traditional flat planting or single wide-narrow row design, the method can significantly reduce the lodging and root rot risk caused by field waterlogging, further enhance the uniformity and stress resistance of plant groups, and provide a good group foundation for realizing the dual goals of corn kernel yield and straw feeding quality. DETAILED DESCRIPTION

[0031] The technical solutions in the embodiments of the application will be clearly and completely described below with reference to the embodiments of the application. Obviously, the described embodiments are only part of the embodiments of the application, rather than all the embodiments of the application. Based on the embodiments in the application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the application.

[0032] In the following description, many specific details are set forth in order to provide a thorough understanding of the application, but the application can also be implemented in other ways different from those described herein, therefore, the scope of protection of the application is not limited by the specific embodiments disclosed below.

[0033] In the description of the present application, it needs to be understood that the terms "center", "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and the like indicate the orientation or positional relationship based on the shown orientation or positional relationship, only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the indicated device or element must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the scope of protection of the present application. In addition, the terms "first", "second" and the like are only for the purpose of description and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined with "first", "second" and the like can be explicitly or implicitly included one or more. In the description of the present application, unless otherwise specified, the meaning of "a plurality of" is two or more.

[0034] In the description of the present application, it needs to be understood that unless otherwise explicitly specified and limited, the terms "mounting", "connection", "connection" should be understood in a broad sense, for example, it can be fixed connection, or detachable connection, or integral connection; it can be mechanical connection, or electrical connection; it can be directly connected, or indirectly connected through intermediate medium, it can be the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood through specific circumstances.

[0035] A kind of grain and forage dual-purpose corn cultivation method, comprising the following steps:

[0036] Step S1, selecting grain corn variety, selecting site and soil preparation;

[0037] Step S2, ridging and soil covering, in the suitable sowing period of May 5-15, single grain precision sowing is carried out, and the selected conventional high yield grain corn variety is sown at the density of 5-10% more than the recommended density of specific pure grain;

[0038] Step S3, before the jointing stage, applying base fertilizer and silicon calcium magnesium compound fertilizer at the stem position, and implementing nitrogen fertilizer and silicon calcium fertilizer at the large trumpet stage;

[0039] Step S4, 10-15 days after spinning, green-preserving and kernel-increasing fertilizer is applied, wherein the green-preserving and kernel-increasing fertilizer comprises: potassium fertilizer, urea and phosphorus fertilizer;

[0040] Step S5, at the end of the wax ripening stage to the beginning of the full ripening stage, the kernels are harvested when the kernel milk line disappears or the black layer is formed, and the plant stem and leaf structure that has not completely dried are retained intact;

[0041] Step S6, after harvesting, nitrogen fertilizer is applied, growth hormone is sprayed to induce bud differentiation at the stem base, and the stem base is harvested after the growth returns green.

[0042] In the present application, in step S1,

[0043] Optionally: for convenient irrigation, convenient management, pH 5.8-7, medium or above medium loam or sandy loam;

[0044] Land preparation: after site selection, the land is mechanically rotary plowed to a depth of 20-25 nm, and a drainage ditch is dug.

[0045] In the present application, in step S2, the ridging and soil covering adopts a ridging planting + ditch compartment drainage mode, including: wide row 75-80 cm, narrow row 40-45 cm, ridge height 15-20 cm, ridge top width ≥25 cm, and soil covering thickness range 4-6 cm.

[0046] In step S2, the conventional high-yield grain corn variety density range is 4500-5500 plants / acre.

[0047] Sowing suitable period: May 5-15, within the spring sowing window, select the period when the ground temperature stabilizes through 10-12℃ as the suitable sowing benchmark;

[0048] Early sowing is prone to be affected by low temperature, leading to seed rot, uneven emergence; late sowing compresses the growth period, affecting grain filling and straw green induction;

[0049] The window of May 5-15 takes into account the length of the growth period, the field temperature and humidity environment, and the accumulated temperature required for later green induction.

[0050] The ridging and soil covering mode adopts a ridging planting + ditch compartment drainage mode according to the slope of the plot, the underground water level and the irrigation and drainage conditions, specifically in the following form: wide row 75-80 cm, narrow row 40-45 cm, ridge height 15-20 cm, ridge top width ≥25 cm, and soil covering thickness range 4-6 cm; forming a "group ventilation, individual light competition" layout, which is beneficial to increasing the amount of leaves and stems and reducing the risk of lodging in the later period;

[0051] The soil covering thickness is controlled at 4-6 cm to ensure uniform emergence and avoid "false deep planting" or "bud dry seedling death".

[0052] The sowing method adopts single-grain precision dibbling, using coated corn seeds to improve seedling resistance and control underground pests, with only one seed per hole, effectively controlling seed usage, avoiding "heavy seedlings and lack of seedlings", and improving the consistency of individual performance.

[0053] It should be noted that after sowing, timely compacting and compacting the soil around the seed trench can promote the soil capillary water replenishment efficiency, improve the emergence speed and uniformity, and enhance the wind resistance of seeds and young roots, which is beneficial to the subsequent healthy development of straw roots and provides a basis for regeneration induction.

[0054] The cultivation structure design mode of wide-narrow row staggered + ridging planting + ditch compartment drainage is adopted in the ridging and covering stage, which not only optimizes the spatial distribution of the corn plant population, but also improves the ventilation and light transmittance between plants and the drainage efficiency after rain, and by reasonably controlling the ridge height and the covering thickness, the root system is more easily to penetrate the soft soil layer, and the absorption capacity of the root system to elements such as silicon, calcium and magnesium is improved, so as to strengthen the utilization efficiency of water and fertilizer of the plant, compared with the traditional flat planting or single wide-narrow row design, the method can significantly reduce the lodging and root rot risk caused by field waterlogging, further enhance the uniformity and resistance of the plant population, and provide a good population foundation for realizing the dual goals of corn grain yield and straw feeding quality.

[0055] In the present application, in step S3, the base fertilizer is phosphorus and potassium fertilizer, the base fertilizer application amount is 20-25 kg / acre, and the silicon, calcium and magnesium compound fertilizer application amount is 30-40 kg / acre.

[0056] The nitrogen fertilizer is urea, in step S3, the nitrogen fertilizer application amount is 20-22 kg / acre, the silicon and calcium fertilizer application amount is 10-15 kg / acre in the row, and the deep application is covered with soil, wherein the effective SiO2 content in the silicon and calcium fertilizer is ≥25%.

[0057] Before the jointing stage, the crop root activity is enhanced, and the leaf blade is rapidly expanded, which is an important window period for determining the potential of the nutrient organ, at this time, applying base fertilizer and silicon, calcium and magnesium compound fertilizer is a key measure to enhance the stem mechanical strength, improve the plant lodging resistance and green retention, wherein:

[0058] The base fertilizer is mainly phosphorus and potassium fertilizer (such as diammonium phosphate, potassium chloride, etc.), and the application amount is 20-25 kg / acre, which is used to enhance the root activity of the plant, promote the synthesis and transportation of photosynthetic products, and enhance the overall nutrient utilization efficiency;

[0059] The silicon, calcium and magnesium compound fertilizer is used to synergistically strengthen the plant structure with medium and trace elements, and the application amount is 30-40 kg / acre, and the annular fertilization (or ditching) is carried out at the stem base to ensure that the main nutrients are fully absorbed at the inter-node of rapid growth;

[0060] The effective SiO2 content needs to be ≥25%, which mainly forms a siliceous reinforcement layer by depositing on the cell wall, significantly improves the stem mechanical support, and at the same time, the calcium and magnesium elements assist in maintaining the stability of the cell membrane and the photosynthetic function of the leaf blade, effectively delaying the early senescence.

[0061] The silicon calcium magnesium compound fertilizer is implemented, especially positioned in the stem growth zone before the jointing stage, combined with the drip irrigation belt application and deep application technology, so that the silicon element can be fully absorbed by the root system and transported to the aboveground part, the silicon element can significantly enhance the cell wall structure, improve the mechanical strength of the plant and the resistance to adversity, especially has a direct gain on the corn resistance to lodging, disease and insect pests and drought resistance, through the synergistic regulation of trace elements in calcium, magnesium and silicon, the stem support structure and the overall health of the plant are strengthened, which provides stable morphological support for the double round harvesting in the later period, and also promotes the synthesis of chlorophyll and the sustainability of photosynthetic efficiency.

[0062] Into the big horn period, the corn growth enters the peak stage of nutrient transformation in the pre-grain period, at this time the biomass accumulation speed is fast, and the demand for nitrogen increases sharply. In this stage, the strategy of combined application of nitrogen fertilizer and silicon calcium fertilizer is adopted, which has multiple effects of strengthening the potential of grain formation, stabilizing the function of middle and upper stems and leaves, and enhancing the potential of later regreening:

[0063] The nitrogen fertilizer is urea, and the application amount is 20-22 kg / acre, which is applied by deep application of drip irrigation belt to improve the utilization rate of fertilizer efficiency and reduce the loss of volatilization;

[0064] The matching silicon calcium fertilizer is applied at 10-15 kg / acre, which is applied by deep application in the ditch covered with soil to ensure that the plant resistance and structural integrity are simultaneously enhanced during the differentiation and formation of grains;

[0065] The silicon fertilizer continuously enhances the leaf angle retention and straightness in this stage, which helps to maintain the light distribution of the group, and the calcium and magnesium elements help to improve the photosynthetic rate and the coordination of carbon and nitrogen metabolism, laying a nutritional and physiological foundation for subsequent grain filling and straw regeneration.

[0066] It should be noted that nitrogen and potassium are supplemented in the big horn period to match the changes of key nutrient requirements in the corn growth period, and the dynamic fertilization mechanism of promoting in the early stage, stabilizing in the middle stage and preserving green in the later stage is followed. The potassium and phosphorus supplement in the base fertilizer can promote root development and early photosynthetic foundation establishment, and the nitrogen supplement after the jointing stage can help to enhance chlorophyll accumulation of leaves and prolong the photosynthetic duration. Compared with the conventional constant amount uniform application method, the present method precisely matches the peak period of nutrient absorption of corn, improves the biological utilization rate of unit nutrient, reduces the risk of nitrogen leaching and resource waste, further promotes the activity of stems and leaves in the middle and late stages, and helps to form strong regenerative seedlings in the subsequent induction regeneration stage.

[0067] In the present application, in step S4, the green-keeping and grain-increasing fertilizer includes: potassium fertilizer, urea and phosphorus fertilizer;

[0068] The composition ratio between the potassium fertilizer, urea, phosphorus fertilizer and trace elements is 60-70:15-20:5-10, wherein the application amount of potassium fertilizer is 10-15 kg / acre, the application amount of urea is 3-5 kg / acre, and the application amount of phosphorus fertilizer is 1-2 kg / acre.

[0069] Step S4 is located after the silking pollination to the initial stage of grain filling, at this time, it is the peak of nutrient transport for grain filling formation, and it is also the key window for determining the greenness of the plant, photosynthetic efficiency and the nutritional value of the later stage of straw, and the traditional high yield corn cultivation often causes the decrease of straw nutrition due to rapid dehydration and early leaf senescence, which is not conducive to silage or regreening, and the present step is a key management link for making up for this disadvantage.

[0070] At this stage, the green-preserving and grain-increasing fertilizer is applied, which is composed of potassium fertilizer, nitrogen fertilizer (urea) and phosphorus fertilizer, and the component ratio is controlled as potassium fertilizer:nitrogen fertilizer:phosphorus fertilizer=60-70:15-20:5-10; wherein, the potassium fertilizer is potassium sulfate or potassium chloride, and the application amount is 10-15 kg / acre; the nitrogen fertilizer is urea, and the amount is 3-5 kg / acre; and the phosphorus fertilizer is 1-2 kg / acre.

[0071] Among them, potassium can promote carbohydrate synthesis and transport, maintain stomatal regulation and enhance drought resistance, effectively alleviate early senescence caused by high temperature or water deficiency, at the same time, appropriate nitrogen fertilizer can maintain leaf chlorophyll content, inhibit protein degradation and improve photosynthetic potential, instead of inhibiting dehydration or causing greed for green as traditional high-dose nitrogen fertilizer; and phosphorus fertilizer can ensure smooth energy transport and assist grain milk line advancement.

[0072] In terms of application method, the green-preserving and grain-increasing fertilizer is applied synchronously with watering, so that the fertilizer effect is more uniform and penetrates to the root active area, the absorption efficiency is enhanced, and a nutrient slow-release and slow-decay barrier is formed in the leaves and stems after the fertilizer is applied, which on the one hand guarantees the continuous photosynthesis to support the grain filling, and on the other hand maintains the greenness and water content of the stems and leaves, thereby creating favorable conditions for the later straw silage and induced regeneration.

[0073] Compared with the traditional method of stopping fertilization after silking and allowing natural dehydration and de-greening of pure grain corn, the present step can effectively delay physiological aging, enhance the nutrient retention and regeneration capacity of stems and leaves by precisely controlling the potassium, nitrogen and phosphorus ratio and trace nutrient balance, and finally realize the dual goals of "grain use without yield reduction and feed use with regeneration", which is one of the core technical measures in the grain and feed dual-use cultivation system.

[0074] In the present application, in the early stage of field management, by increasing the application of silicon calcium magnesium compound fertilizer rich in SiO2 and potassium fertilizer and deep applying them in the row, the corn stem structure is significantly strengthened, and the resistance to lodging is improved, the silicon element can be deposited in the cell wall in the corn body, and the mechanical strength is enhanced, at the same time, the calcium and magnesium elements are helpful for cell division and photosynthesis, thereby improving the photosynthetic efficiency and biomass accumulation, during which the potassium fertilizer delays the aging of the plant and enhances the toughness of the stem, and the appropriate amount of nitrogen maintains the leaf activity, thereby successfully breaking the shackles of the traditional grain corn that the stems and leaves are dry and yellow and cannot be utilized at the time of harvest, so that at the time of harvest, the middle and lower stems still have considerable green parts and high water content, thereby providing a material basis for the later greenness and regeneration potential.

[0075] It should be noted that the implementation of the green maintenance granulation fertilizer regulates the translocation of photosynthate and water redistribution process during the grain filling period, realizes the stage regulation of grain dehydration rate, and potassium element promotes the synthesis and transport of sucrose by enhancing the stomatal regulation capacity of leaves, not only speeds up the grain filling, but also promotes the rapid dehydration of grain at the end of grain ripening, thereby shortens the "delayed green" period before harvest, which is different from the problem of slow grain drying and affecting mechanical harvesting in traditional corn cultivation. The present scheme ensures the maintenance of straw green and prolongs the photosynthetic potential, realizes the physiological coordination of grain and straw maturity rhythm, further optimizes the harvest window and reduces the grain storage moisture content.

[0076] In step S5, the present application proposes to harvest at the end of ripening to the beginning of full ripening, and the judgment basis is the disappearance of grain milk line or the formation of black layer. The harvesting strategy of retaining complete stem and leaf structure can maximize the consideration of grain yield and straw forage quality. Harvesting at this key time window not only ensures sufficient grain filling and reduces the grain moisture content to the appropriate threshing condition, but also avoids serious lignification of stems and leaves, thereby obtaining straw with high greenness and moderate moisture content. Compared with the traditional late harvesting method based on the maximization of grain dry matter accumulation, the present method often leads to the increase of cellulose content in straw and poor palatability. The present method realizes the time balance of yield and quality under the guidance of grain and forage, optimizes the final crop structure and improves the overall planting system benefit.

[0077] In step S6, after harvesting, nitrogen fertilizer is applied, the nitrogen fertilizer is urea, the urea application amount is 5-10 kg / acre, and potassium sulfate is applied, the potassium sulfate application amount is 3-5 kg / acre.

[0078] In step S6, the growth hormone includes gibberellin, 6-benzylaminopurine and indole acetic acid; the concentration of gibberellin is 5-10 mg / L, the concentration of 6-benzylaminopurine is 10-20 mg / L, and the concentration of indole acetic acid is 1-2 mg / L.

[0079] The growth hormone is mixed, and 30-40 L / acre is sprayed on the stem base to induce the differentiation of the regenerative bud of the stem base and promote the growth of the stem base.

[0080] Through the implementation of step S4, when the corn kernels are harvested in step S5, the corn stems are still in the process of not being completely lignified and maintaining activity. By applying urea to the corn stems, the application amount is controlled at 5-10 kg / acre, and potassium sulfate with an implementation amount of 3-5 kg / acre is applied, forming a nitrogen-potassium synergistic regenerative nutrient supply. The addition of nitrogen can rapidly promote cell division and differentiation of axillary buds, enhance protein and nucleic acid synthesis, and potassium sulfate can improve water regulation and energy transport capacity, so that the growth vigor of the axillary buds after formation is stronger and the leaf greenness is better.

[0081] Then, the differentiation and development of the latent buds at the stem base are stimulated by a hormone compound regulation system. The selected hormone combinations include: gibberellin 5-10 mg / L to promote cell longitudinal elongation; 6-benzylaminopurine 10-20 mg / L to stimulate axillary bud initiation and germination; indole acetic acid 1-2 mg / L to promote axillary bud rooting and tissue organ formation. After dilution, the mixture of the three is sprayed on the stem base at 30-40 L / acre to construct a "regeneration induction zone" to mobilize the physiological potential in the corn stalk tissue.

[0082] The hormone + nutrient synergistic scheme breaks the dormancy state of the corn stem, guides the latent axillary bud to start cell division, and then develops into regenerative green forage plants. Under suitable temperature and humidity conditions, the plants turn green within 5-10 days and form forage plant groups with high nutrient concentration, tender green leaves, and good stem flexibility within 15-25 days. As green forage raw materials, such regenerative plants not only maintain high digestible energy, protein content, and palatability, but also avoid the risk of energy being concentrated into grains due to the absence of ear emergence, thereby improving the overall quality of silage.

[0083] Compared with the current situation of low efficiency, serious nutrient waste, and high environmental pressure in traditional corn stalk processing after harvesting, this step realizes resource closed-loop utilization through scientific regulation, fully utilizes the stem regeneration ability of grain varieties, and significantly improves the comprehensive output efficiency after land preparation, providing sustainable power for grain-forage dual-purpose cultivation mode.

[0084] It should be noted that the use of silicon calcium magnesium compound fertilizer, potassium fertilizer and nitrogen fertilizer maintains the vitality of corn stems. After grain harvesting, combined with the application of nitrogen fertilizer and the spraying of growth hormone, the differentiation of regenerative buds at the base of the plant stems is induced and the plants turn green again, thereby realizing the secondary growth and utilization of corn stalks. The corn stems and leaves that were in the dry and aging stage can synthesize chlorophyll again and start photosynthesis. Compared with the existing green corn silage, which requires special breeding of green retention varieties and is limited in grain yield, the present invention realizes functional regeneration without changing the variety, provides a post-use value for conventional grain varieties, and further enhances the economic adaptability of cultivation.

[0085] At the same time, the use of regenerative induction means activates the dead stalks into green biomass, not only realizing secondary harvest, but also positively promoting the ecological cycle of the field soil. During the process of returning the green stalks to the field after harvesting, their higher fresh organic matter content, lower C / N ratio, and more easily degradable cell structure help to improve the soil organic matter accumulation speed, improve the soil aggregate structure, and enhance the water and fertilizer retention capacity. Compared with the traditional corn planting, which directly leaves the stubble in the field and has problems such as slow decomposition and disease induction, the present invention effectively solves the problem of poor quality of returning to the field by first turning green and then returning to the field, realizing the double improvement of land quality and production efficiency.

[0086] Verify whether the method of the present patent can make the grain corn retain the greenness of the straw at the grain harvesting stage, and obtain the regenerative straw with the feeding value close to that of the special forage variety in the regreening process after harvesting.

[0087] Example one:

[0088] Select Zhengdan 958 grain corn variety, select soil or sandy loam soil with convenient irrigation, easy management, pH 5.8-7, medium or above fertility, select land after planting, mechanically rotary till the land with a depth of 20-25 nm, and set up drainage ditches;

[0089] Adopt ridge planting + ditch compartment drainage mode, including: wide row 75-80 cm, narrow row 40-45 cm, ridge height 15-20 cm, ridge top width ≥25 cm, and soil cover thickness range 4-6 cm, during the suitable sowing period of May 5-15, carry out single grain precision sowing, and the density range is 5000 plants per mu;

[0090] Before the jointing stage, apply base fertilizer and silicon calcium magnesium compound fertilizer at the stem position, the base fertilizer is phosphorus and potassium fertilizer, the base fertilizer application amount is 25 kg per mu, the silicon calcium magnesium compound fertilizer application amount is 40 kg per mu, implement nitrogen fertilizer and silicon calcium fertilizer at the big bell stage, the nitrogen fertilizer application amount is 22 kg per mu, fertilize through the drip irrigation belt facility, the silicon calcium fertilizer application amount is 15 kg per mu in the row, and deep application and soil cover, wherein, the silicon calcium fertilizer contains effective SiO2≥25%;

[0091] 10-15 days after spinning, apply green-preserving and kernel-increasing fertilizer, wherein the green-preserving and kernel-increasing fertilizer includes: potassium fertilizer, urea and phosphorus fertilizer; the composition ratio between potassium fertilizer, urea, phosphorus fertilizer and trace elements is 60-70:15-20:5-10, wherein the potassium fertilizer application amount is 10-15 kg per mu, the urea application amount is 3-5 kg per mu, and the phosphorus fertilizer application amount is 1-2 kg per mu;

[0092] At the end of the wax ripening stage to the beginning of the full ripening stage, when the grain milk line disappears or the black layer is formed, the grain is harvested, and the plant stem and leaf structure that has not completely dried is retained intact;

[0093] After harvesting, apply nitrogen fertilizer and spray growth hormone to induce bud differentiation at the stem base, and promote the stem base to grow and regreen, wherein the nitrogen fertilizer is urea, the urea application amount is 10 kg per mu, and potassium sulfate is applied, the potassium sulfate application amount is 5 kg per mu; the growth hormone includes: gibberellin, 6-benzylaminopurine and indole acetic acid; the concentration of gibberellin is 10 mg / L, the concentration of 6-benzylaminopurine is 20 mg / L, and the concentration of indole acetic acid is 2 mg / L; mix the growth hormone, and spray 40 L per mu on the stem base to induce bud differentiation at the stem base and promote the stem base to grow and regreen.

[0094] Example two:

[0095] The embodiment one is basically the same as the embodiment one, except that the plants are not induced to turn green, and the grains are harvested, and the stems and leaves of the plants are harvested.

[0096] Embodiment three:

[0097] The embodiment two is basically the same as the embodiment two, except that the silage corn variety No. 101 is used.

[0098] The stems and leaves of the plants harvested in the embodiment one to the embodiment three are detected, as shown in Table 1.

[0099] 1. Chlorophyll content detection: the SPAD-502 chlorophyll meter is used to detect the back of the middle functional leaves, 10 plants are taken for detection, and the average value is recorded.

[0100] 2. Straw moisture content: the stem sample is taken, dried at 105 ℃ to constant weight, and the formula: moisture content = (wet weight-dry weight) / wet weight x 100%.

[0101] 3. Crude protein content: the FOSS Kjeltec 8400 nitrogen determination instrument is used for detection, the sample is crushed through a 1 mm screen, 1 g of sample is taken, and digestion, distillation and titration are performed; crude protein = total nitrogen x 6.25.

[0102] 4. ADF content: the ANKOM A200 fiber analyzer is used for detection.

[0103] 5. DDM: calculated using the ADF content: DDM = 88.9-0.779 x ADF.

[0104] Table 1:

[0105] Example 1 Example 2 Example 3 Chlorophyll content (%) 36.2 24.1 42.5 Moisture content (%) 68.4 55.7 73.2 Crude protein content (%) 6.9 5.1 7.5 ADF content (%) 30.5 35.6 28.4 DDM (%) 64.1 60.2 66.8

[0106] In summary, it can be concluded that the grain corn obtained by the cultivation method of the present application has silage forage which is basically the same as that of silage corn and higher than that of traditional cultivation of grain corn. The main reason is that the present application increases the application of silicon calcium magnesium compound fertilizer and potassium fertilizer rich in SiO2. Silicon elements can be deposited in cell walls in the body of corn, enhancing mechanical strength. At the same time, calcium and magnesium elements help cell division and photosynthesis, thereby improving photosynthetic efficiency and biomass accumulation. During this period, potassium fertilizer delays plant senescence and enhances stem toughness. In addition, a proper amount of nitrogen is used to maintain leaf activity. The present application successfully breaks the shackles of traditional grain corn harvesting when the stems and leaves are dry and yellow and cannot be utilized. Therefore, the middle and lower stems still have a considerable green part and a higher moisture content at the time of corn harvesting. Combined with the application of nitrogen fertilizer and the spraying of auxin, the plant stem base is induced to regenerate bud differentiation and turn green again, thereby realizing the secondary growth and utilization of corn straw. The corn stems and leaves in the dry and aging stage can synthesize chlorophyll again and start photosynthesis.

[0107] Compared with the existing silage corn which needs special breeding of green-keeping varieties and has limited grain yield, the application realizes functional regeneration without changing the variety, provides late reuse value for conventional grain varieties, and further enhances the economic adaptability of cultivation.

[0108] The above is based on the ideal embodiment of the application, through the above description, relevant personnel can make various changes and modifications without deviating from the technical idea of the application. The technical scope of the application is not limited to the content of the specification, and the technical scope must be determined according to the scope of claims.

Claims

1. A method for cultivating corn for both food and feed, characterized in that: The following steps are involved: Step S1: selecting grain corn varieties, selecting land and preparing the land; Step S2: Ridge and soil covering, and carry out single-seed precision sowing during the suitable sowing period from May 5 to 15, sowing the selected conventional high-yield grain corn variety at a density 5-10% higher than the recommended density for pure grain; Step S3: Apply base fertilizer and silicon-calcium-magnesium compound fertilizer to the stems before the jointing stage, and apply nitrogen fertilizer and silicon-calcium fertilizer during the flaring stage; Step S4, applying green-keeping and grain-increasing fertilizer 10 to 15 days after silking, wherein the green-keeping and grain-increasing fertilizer includes: potassium fertilizer, urea and phosphate fertilizer; Step S5: harvesting the seeds when the milk line disappears or a black layer forms at the end of the waxy stage to the beginning of the fully ripe stage, leaving the stem and leaf structures of the plants that have not yet completely dried intact; Step S6: After harvesting, topdressing with nitrogen fertilizer and spraying with growth hormone to induce differentiation of regenerated buds at the stem base, prompting the stem base to grow green again and then harvesting the stem base.

2. The method for cultivating corn for both food and feed according to claim 1, wherein: In the step S1; Site selection: Loam or sandy loam with convenient irrigation and drainage, easy management, pH between 5.8-7, and medium or above fertility; Land preparation: After selecting the site, the land is tilled mechanically to a depth of 20-25nm and drainage ditches are opened.

3. The method for cultivating corn for both food and feed according to claim 1, wherein: In step S2, ridge-forming and soil-covering adopts a ridge-forming planting + furrow drainage mode, including: row width 75-80 cm, narrow row 40-45 cm, ridge height 15-20 cm, ridge top width ≥ 25 cm, and soil-covering thickness ranging from 4 to 6 cm.

4. The method for cultivating corn for both food and feed according to claim 1, wherein: In step S2, the density of conventional high-yield grain corn varieties ranges from 4,500 to 5,500 plants per mu.

5. The method for cultivating corn for both food and feed according to claim 1, wherein: In step S3, the base fertilizer is phosphorus and potassium fertilizer, the application amount of the base fertilizer is 20-25 kg / mu, and the application amount of silicon-calcium-magnesium compound fertilizer is 30-40 kg / mu.

6. The method for cultivating corn for both food and feed according to claim 1, wherein: The nitrogen fertilizer is urea. In step S3, the nitrogen fertilizer application rate is 20-22 kg / mu, and fertilization is carried out through a drip irrigation belt facility. The silicon-calcium fertilizer application rate is 10-15 kg / mu between rows, and deep application is carried out and covered with soil. The effective SiO2 content in the silicon-calcium fertilizer is ≥25%.

7. The method for cultivating corn for both food and feed according to claim 1, wherein: In step S4, the green-keeping and granulation-enhancing fertilizer includes: potash fertilizer, urea and phosphate fertilizer; The composition ratio between potassium fertilizer, urea, phosphorus fertilizer and trace elements is 60-70:15-20:5-10, among which the application amount of potassium fertilizer is 10-15kg / mu, the application amount of urea is 3-5kg / mu, and the application amount of phosphorus fertilizer is 1-2kg / mu.

8. The method for cultivating corn for both food and feed according to claim 1, wherein: In step S6, nitrogen fertilizer is applied after harvesting, and the nitrogen fertilizer is urea, and the application amount of urea is 5-10 kg / mu, and potassium sulfate is applied in combination, and the application amount of potassium sulfate is 3-5 kg / mu.

9. The method for cultivating corn for both food and feed according to claim 1, wherein: In step S6, the growth hormone includes: gibberellin, 6-benzylaminopurine and indoleacetic acid; the gibberellin concentration is 5-10 mg / L, the 6-benzylaminopurine concentration is 10-20 mg / L, and the indoleacetic acid concentration is 1-2 mg / L; Mix the growth hormones and spray them on the base of the stem at 30-40 L / mu to induce the differentiation of regenerated buds at the base of the stem and promote its growth and greening.