A method for inducing simultaneous emergence of fresh corn seeds

Abstract

The present application relates to a method for inducing synchronous emergence of fresh corn seeds, belonging to the field of agricultural technology, wherein the fresh corn seeds are soaked in a complex microbial inoculum containing red-pink red ball bacteria, methylobacterium extorquens and argumentous bacteriophage liquid microbial inoculum at a volume ratio of 1:2-3:1-2 after disinfection and air drying, and then sowed and germinated after re-drying treatment, which can effectively induce synchronous emergence of fresh corn, improve the uniformity of emergence, and facilitate unified management and harvesting in the later planting process.

Description

Technical Field

[0001] This invention belongs to the field of agricultural technology, and more specifically, relates to a method for inducing the synchronous emergence of fresh corn seeds. Background Technology

[0002] Sweet corn seeds (especially super sweet corn) have insufficient starch accumulation and high soluble sugar content in their endosperm. Mature seeds are often shriveled and dry, with a small endosperm volume and loose texture. This unique structure leads to generally low seed vigor, significant differences in vigor between individuals, and a high susceptibility to imbibition damage during imbibition. Furthermore, they are extremely sensitive to environmental factors such as soil temperature, moisture, and oxygen. Under field sowing conditions, sweet corn seeds often exhibit delayed emergence, low emergence rates, and severe uneven seedling size, with emergence times for the same batch of seeds varying by 3-5 days or even longer. Uneven emergence directly results in inconsistent plant growth stages, increasing the dispersion of silking and pollen shedding periods. This not only affects pollination quality and ear uniformity and marketability but also poses significant challenges to mechanized and unified harvesting.

[0003] Seed priming technology is widely used to improve the germination performance of sweet corn seeds. Seed priming involves controlling the slow water absorption of the seed, allowing it to gradually complete its pre-germination physiological and biochemical metabolism without the radicle breaking through the seed coat. The seed is then dried and stored. After sowing, primed seeds exhibit faster germination rates, higher germination potential, and enhanced stress resistance. Common priming methods include polyethylene glycol osmotic priming, salt priming, water priming, drum priming, and biological priming. These methods, by adjusting osmotic potential or water supply, promote cell membrane system repair, increase antioxidant enzyme activity, and enhance nucleic acid repair capacity, thus playing a role in improving average germination rate and average germination speed.

[0004] However, existing germination techniques primarily focus on improving the average germination performance of seed populations, lacking targeted solutions for effectively reducing the differences in emergence time among individuals within a population and achieving highly synchronized emergence. This problem is particularly prominent for sweet corn seeds, where significant differences in vigor within the population are a major concern: some low-vigor seeds may fail to initiate normal metabolic processes during germination, or their processes may be significantly delayed; while high-vigor seeds, under the same conditions, may prematurely approach germination due to excessively rapid metabolism. Current germination methods often employ constant water potential, continuous aeration, or single temperature and humidity control, failing to provide differentiated metabolic calibration for seeds with varying vigor levels. This results in a faster average germination rate after treatment, but still uneven physiological progress among individuals, leading to a relatively wide emergence time window in the field and an inability to meet the production requirements of precision direct seeding and mechanized harvesting.

[0005] Some studies have attempted to improve seedling uniformity by adjusting the initiation time or increasing oxygen supply. However, due to the unique sugar metabolism background of fresh sweet corn seeds, simply extending the initiation time or increasing dissolved oxygen levels can easily cause high-vitality seeds to germinate prematurely, while low-vitality seeds still respond slowly, and the problem of uneven seedling emergence remains unresolved. Furthermore, even after initiation and drying using existing methods, when seeds absorb water again at sowing, there is still a significant time lag between individual seeds during the process from water absorption to the radicle breaking through the seed coat, making it difficult to achieve a burst of synchronized emergence.

[0006] In summary, a seed priming method can effectively target the characteristics of fresh sweet corn seeds, significantly compress the time window for field emergence of seeds from the same batch, and achieve synchronous emergence. This is precisely the technical problem that urgently needs to be solved in this field. Summary of the Invention

[0007] To address the shortcomings of existing technologies, this invention provides a method for inducing synchronous emergence of fresh corn seeds. The method described in this invention can effectively induce synchronous emergence of fresh corn, improve the uniformity of emergence, and facilitate unified management and harvesting during the later planting process.

[0008] To achieve the above-mentioned objectives, the present invention provides the following technical solution: This invention provides a method for inducing simultaneous germination of fresh corn seeds, comprising the following steps: S1, Seed pretreatment: Select fresh corn seeds, soak them in 0.5% hydrogen peroxide solution for 10-12 minutes for disinfection, and rinse them 5 times with sterile deionized water; S2, Microbial initiation: Add a compound microbial agent to the pretreated seeds at a ratio of 1-1.2 L per kilogram of seeds, and soak for 12-18 hours; the compound microbial agent contains *Rhodococcus rubrum* (red-flat cocci) in a volume ratio of 1:2-3:1-2. Rhodococcus erythropolis ), Methylobacterium truncatum ( Methylobacterium extorquens ) and the debate about gluttony ( Variogorax paradoxus Liquid bacterial agent.

[0009] S3, Re-drying treatment: After soaking, the seeds are dried in an airflow at 26℃ and relative humidity below 30% until the moisture content is 13%-14%; S4, Sowing and Germination: Sow the dried fresh corn seeds in the substrate. When sowing, lay the seeds flat and cover them with a 1-2 cm thick layer of substrate. Germinate the seeds at 28-35℃ and relative humidity ≥90%.

[0010] Furthermore, in step S1: select fresh corn seeds that are free from obvious pests, diseases, and mechanical damage.

[0011] Further, the preparation method of Rhodococcus rubrum liquid inoculum in step S2 is as follows: Rhodococcus rubrum liquid inoculum is inoculated into a liquid fermentation medium at a ratio of 3%-4%, and fermented at 28-30℃ and 180-200 rpm for 24-36 hours with stirring. After fermentation, the mixture is filtered and diluted until the effective viable count in the liquid inoculum is 1×10⁻⁶. 8 CFU / mL yields a liquid inoculum of Rhodococcus rubrum; the liquid fermentation medium contains: 10 g / L peptone, 3 g / L beef meal and 5 g / L sodium chloride, pH=7.3-7.5.

[0012] Further, the preparation method of the liquid inoculum of *Methylobacterium tumefaciens* in step S2 is as follows: *Methylobacterium tumefaciens* liquid inoculum is inoculated into a liquid fermentation medium at a ratio of 5%-6%, and fermented at 28-30℃ and 200-220 rpm for 48-72 hours with stirring. After fermentation, the inoculum is filtered and diluted until the effective viable count in the liquid inoculum is 1×10⁻⁶. 8 The CFU / mL concentration yields a liquid inoculum of *Methylobacterium tumefaciens*. The liquid fermentation medium contains 10 g / L peptone, 3 g / L beef meal, and 5 g / L sodium chloride, with a pH of 7.3-7.5.

[0013] Further, the preparation method of the *Burkholderia fulvidraco* liquid inoculum in step S2 is as follows: *Burkholderia fulvidraco* liquid inoculum is inoculated into a liquid fermentation medium at a ratio of 4%-6%, and fermented at 30-32℃ and 180-200 rpm for 36-48 hours with stirring. After fermentation, the inoculum is filtered and diluted until the effective viable count in the liquid inoculum is 1×10⁻⁶. 8 The concentration of CFU / mL yields the liquid inoculum of the glutathione; the liquid fermentation medium contains: 10 g / L peptone, 3 g / L beef meal and 5 g / L sodium chloride, pH=7.3-7.5.

[0014] Beneficial effects: The method described in this invention can effectively induce synchronous emergence of fresh corn seedlings, improve seedling uniformity, and facilitate unified management and harvesting during the later planting process. Detailed Implementation

[0015] The present invention will be described in detail below with reference to the embodiments, but these should not be construed as limiting the scope of protection of the present invention.

[0016] The Rhodococcus rubrum used in this embodiment is ( Rhodococcus erythropolis ) and the debate about gluttony ( Variogorax paradoxus The liquid bacterial agent was purchased from Beina Chuanglian Biotechnology Co., Ltd., with strain numbers BNCC335160 and BNCC369655; *Methylobacterium tumefaciens* (… Methylobacterium extorquensPurchased from Ningbo Mingzhou Biotechnology Co., Ltd., strain number BMZ012930.

[0017] The preparation method of Rhodococcus rubrum liquid inoculum is as follows: Rhodococcus rubrum liquid inoculum is inoculated into a liquid fermentation medium at a ratio of 3%-4%, and fermented at 28-30℃ and 180-200 rpm for 24-36 hours with stirring. After fermentation, the inoculum is filtered and diluted to a viable count of 1×10⁻⁶ cells / mL. 8 CFU / mL yields a liquid inoculum of Rhodococcus rubrum; the liquid fermentation medium contains: 10 g / L peptone, 3 g / L beef meal and 5 g / L sodium chloride, pH=7.3-7.5.

[0018] The preparation method of the liquid inoculum of *Methylobacterium tumefaciens* is as follows: Liquid *Methylobacterium tumefaciens* inoculum is inoculated into a liquid fermentation medium at a ratio of 5%-6%, and fermented at 28-30℃ and 200-220 rpm for 48-72 hours with stirring. After fermentation, the inoculum is filtered and diluted to a viable count of 1×10⁻⁶ bacteria. 8 The CFU / mL concentration yields a liquid inoculum of *Methylobacterium tumefaciens*. The liquid fermentation medium contains 10 g / L peptone, 3 g / L beef meal, and 5 g / L sodium chloride, with a pH of 7.3-7.5.

[0019] The preparation method of the liquid inoculum of *Gnaphalium affine* is as follows: *Gnaphalium affine* liquid inoculum is inoculated into a liquid fermentation medium at a ratio of 4%-6%, and fermented at 30-32℃ and 180-200 rpm for 36-48 hours with stirring. After fermentation, the inoculum is filtered and diluted to a viable count of 1×10⁻⁶ cells / mL. 8 The concentration of CFU / mL yields the liquid inoculum of the glutathione; the liquid fermentation medium contains: 10 g / L peptone, 3 g / L beef meal and 5 g / L sodium chloride, pH=7.3-7.5.

[0020] Example 1 A method for inducing simultaneous germination of sweet corn seeds includes the following steps: S1, Seed pretreatment: Select fresh corn seeds without obvious diseases, pests and mechanical damage, soak them in 0.5% hydrogen peroxide solution for 11 minutes for disinfection, and rinse them 5 times with sterile deionized water. S2, Microbial initiation: Add a compound microbial agent to the pretreated seeds at a ratio of 1.1 L per kilogram of seeds, and soak for 16 hours; the compound microbial agent contains *Rhodococcus rubrum* (red-spotted) in a volume ratio of 1:2.5:1.5. Rhodococcus erythropolis ), Methylobacterium truncatum ( Methylobacterium extorquens ) and the debate about gluttony ( Variogorax paradoxus Liquid bacterial agent.

[0021] S3, Re-drying treatment: After soaking, the seeds are dried in an airflow at 26℃ and relative humidity below 30% until the moisture content is 13%-14%; S4, Sowing and Germination: Sow the dried fresh corn seeds in the substrate. When sowing, lay the seeds flat and cover them with a 1-2 cm thick layer of substrate. Germinate the seeds at 28-35℃ and relative humidity ≥90%.

[0022] Example 2 A method for inducing simultaneous germination of sweet corn seeds includes the following steps: S1, Seed pretreatment: Select fresh corn seeds without obvious diseases, pests and mechanical damage, soak them in 0.5% hydrogen peroxide solution for 10 minutes for disinfection, and rinse them 5 times with sterile deionized water. S2, Microbial initiation: Add compound microbial agent to the pretreated seeds at a ratio of 1L per kilogram of seeds, and soak for 12 hours; the compound microbial agent contains *Rhodococcus rubrum* in a volume ratio of 1:2:1. Rhodococcus Red City ), Methylobacterium truncatum ( Methylobacterium extorquens ) and the debate about gluttony ( Variogorax paradoxus Liquid bacterial agent.

[0023] S3, Re-drying treatment: After soaking, the seeds are dried in an airflow at 26℃ and relative humidity below 30% until the moisture content is 13%-14%; S4, Sowing and Germination: Sow the dried fresh corn seeds in the substrate. When sowing, lay the seeds flat and cover them with a 1-2 cm thick layer of substrate. Germinate the seeds at 28-35℃ and relative humidity ≥90%.

[0024] Example 3 A method for inducing simultaneous germination of sweet corn seeds includes the following steps: S1, Seed pretreatment: Select fresh corn seeds without obvious diseases, pests and mechanical damage, soak them in 0.5% hydrogen peroxide solution for 12 minutes for disinfection, and rinse them 5 times with sterile deionized water. S2, Microbial initiation: Add compound microbial agent to the pretreated seeds at a ratio of 1.2 L per kilogram of seeds, and soak for 18 hours; the compound microbial agent contains *Rhodococcus rubrum* in a volume ratio of 1:3:2. Rhodococcus Red City ), Methylobacterium truncatum ( Methylobacterium extorquens ) and the debate about gluttony ( Variogorax paradoxus Liquid bacterial agent.

[0025] S3, Re-drying treatment: After soaking, the seeds are dried in an airflow at 26℃ and relative humidity below 30% until the moisture content is 13%-14%; S4, Sowing and Germination: Sow the dried fresh corn seeds in the substrate. When sowing, lay the seeds flat and cover them with a 1-2 cm thick layer of substrate. Germinate the seeds at 28-35℃ and relative humidity ≥90%.

[0026] Comparative Example 1 The difference between Comparative Example 1 and Example 1 is that the compound bacterial agent does not contain Rhodococcus rubrum liquid bacterial agent.

[0027] Comparative Example 2 The difference between Comparative Example 2 and Example 1 is that the compound bacterial agent does not contain Bacillus thuringiensis liquid bacterial agent.

[0028] Comparative Example 3 The difference between Comparative Example 3 and Example 1 is that the compound bacterial agent does not contain the controversial liquid bacterial agent of *Bacillus ventriculatus*.

[0029] Experimental Example Following the methods of Examples 1 to 3 and Comparative Examples 1 to 3, seedling trays were used to induce germination of fresh corn seeds. A blank control group was set up, which was identical to Example 1 except that step S2 was replaced with soaking in water. One hundred corn seeds were sown for each treatment, with three replicates. The germination status of the corn seeds was observed every 6 hours after sowing (germination was considered complete when green corn seedlings emerged from the soil), and the germination time was recorded. If no germination occurred for two consecutive days after the start of germination statistics, the statistics were terminated, and the ungerminated seeds were considered waste seeds.

[0030] Average germination time = germination time of all germinating seeds / total number of seeds - number of waste seeds; The germination times of fresh corn seeds in Examples 1-3, Comparative Examples 1-3, and the control group are shown in Table 1 below. Table 1. Statistics on seed emergence of fresh maize under different treatments As can be seen from Table 1 above, the method of the present invention can effectively shorten the germination time of fresh corn and unify the emergence time.

[0031] The above description is merely a preferred embodiment of the present invention. It should be understood that the present invention is not limited to the forms disclosed herein and should not be construed as excluding other embodiments. It can be used in various other combinations, modifications, and environments, and can be altered within the scope of the concept described herein through the above teachings or related technologies or knowledge. Modifications and variations made by those skilled in the art that do not depart from the spirit and scope of the present invention should be within the protection scope of the appended claims.

Claims

1. A method for inducing simultaneous germination of fresh corn seeds, characterized in that: Includes the following steps: S1, Seed pretreatment: Select fresh corn seeds, soak them in 0.5% hydrogen peroxide solution for 10-12 minutes for disinfection, and rinse them 5 times with sterile deionized water; S2, Microbial initiation: Add a compound microbial agent to the pretreated seeds at a ratio of 1-1.2 L per kilogram of seeds, and soak for 12-18 hours; the compound microbial agent contains *Rhodococcus rubrum* (red-flat cocci) in a volume ratio of 1:2-3:1-2. Rhodococcus erythropolis ), Methylobacterium truncatum ( Methylobacterium extorquens ) and the debate about gluttony ( Variovorax paradoxus Liquid bacterial agent; S3, Re-drying treatment: After soaking, the seeds are dried in an airflow at 26℃ and relative humidity below 30% until the moisture content is 13%-14%; S4, Sowing and Germination: Sow the dried fresh corn seeds in the substrate. When sowing, lay the seeds flat and cover them with a 1-2 cm thick layer of substrate. Germinate the seeds at 28-35℃ and relative humidity ≥90%.

2. The method for inducing simultaneous emergence of fresh corn seeds according to claim 1, characterized in that: In step S1: Select fresh corn seeds that are free from obvious pests, diseases, and mechanical damage.

3. The method for inducing simultaneous emergence of fresh corn seeds according to claim 1, characterized in that: The preparation method of Rhodococcus rubrum liquid inoculum in step S2 is as follows: Rhodococcus rubrum liquid inoculum is inoculated into a liquid fermentation medium at a ratio of 3%-4%, and fermented at 28-30℃ and 180-200 rpm for 24-36 hours with stirring. After fermentation, the inoculum is filtered and diluted until the effective viable count in the liquid inoculum is 1×10⁻⁶. 8 CFU / mL yields a liquid inoculum of Rhodococcus rubrum; the liquid fermentation medium contains: 10 g / L peptone, 3 g / L beef meal and 5 g / L sodium chloride, pH=7.3-7.

5.

4. The method for inducing simultaneous emergence of fresh corn seeds according to claim 1, characterized in that: The preparation method of the liquid inoculum of *Methylobacterium tumefaciens* in step S2 is as follows: Inoculate the liquid inoculum of *Methylobacterium tumefaciens* into a liquid fermentation medium at a ratio of 5%-6%, and ferment at 28-30℃ and 200-220 rpm for 48-72 hours with stirring. After fermentation, filter and dilute until the effective viable count in the liquid inoculum is 1×10⁻⁶. 8 The CFU / mL concentration yields a liquid inoculum of *Methylobacterium tumefaciens*. The liquid fermentation medium contains 10 g / L peptone, 3 g / L beef meal, and 5 g / L sodium chloride, with a pH of 7.3-7.

5.

5. The method for inducing simultaneous emergence of fresh corn seeds according to claim 1, characterized in that: The preparation method of the *Burkholderia glutinis* liquid inoculum in step S2 is as follows: *Burkholderia glutinis* liquid inoculum is inoculated into a liquid fermentation medium at a ratio of 4%-6%, and fermented at 30-32℃ and 180-200 rpm for 36-48 hours with stirring. After fermentation, the inoculum is filtered and diluted to a viable count of 1×10⁻⁶ bacteria. 8 The concentration of CFU / mL yields the liquid inoculum of the glutathione; the liquid fermentation medium contains: 10 g / L peptone, 3 g / L beef meal and 5 g / L sodium chloride, pH=7.3-7.5.

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