Method for increasing nitrogen use efficiency of peanuts by applying molybdenum to root zone

Abstract

Disclosed in the present invention is a method for increasing the nitrogen use efficiency of peanuts by applying molybdenum to a root zone, specifically comprising the following steps: (1) land preparation and fertilization: selecting appropriate land, uniformly spreading a decomposed household organic fertilizer, a nitrogen-phosphorus-potassium compound fertilizer and ammonium molybdate as a base fertilizer, and performing plowing and ridging; (2) seed selection and seed dressing: selecting an early-mid maturing, high-quality, disease-resistant and stress-resistant peanut variety, performing shelling after sun-drying, selecting healthy and plump kernels as seeds, using ammonium molybdate for seed dressing, or using an ammonium molybdate solution for seed soaking, and then performing sowing timely; (3) field management: spraying the ammonium molybdate solution to leaf surfaces separately in a seedling stage and a flowering-pegging stage; and (4) harvesting and storage: performing harvesting timely, and performing drying and storage. In the present invention, the molybdenum applying mode can improve the root morphology of peanuts, enhance the photosynthetic capacity of leaves, increase nitrogen transferred into pods, and increase the accumulation and yield of dry matter of peanuts, thereby improving the nitrogen uptake and utilization, and finally greatly increasing the yield per mu of the peanuts.

Description

A method for improving nitrogen utilization efficiency of peanuts by applying molybdenum to the root zone Technical Field

[0001] The present invention relates to the technical field of crop planting, and more particularly to a method for improving nitrogen utilization efficiency of peanuts by applying molybdenum to the root zone. Background Art

[0002] China is a major agricultural country, and its nitrogen fertilizer consumption accounts for 30% of the world's total consumption. However, the utilization rate of nitrogen fertilizer is only 30%-40%. From a global perspective, it is expected that nitrogen consumption will increase to 13×10 by 2050. 9 -15×10 9 t / year. Low fertilizer use efficiency is a common problem with chemical fertilizers. Nitrogen losses are particularly severe in chemical fertilizers. Much of this excess nitrogen fertilizer is lost to the environment, leading to eutrophication of surface waters, excessive nitrate nitrogen levels in groundwater, and increased greenhouse gas emissions such as NO.

[0003] Peanuts are an important oil crop and cash crop in my country. They are rich in fat and protein, and contain various vitamins such as thiamine, riboflavin, niacin, etc. They are also rich in minerals, especially essential amino acids for the human body. They can promote the development of brain cells and enhance memory. They can be eaten or used as feed. They are both important industrial raw materials and major export commodities. They have a wide range of uses and occupy an important position in the national economy.

[0004] In recent years, the planting area of ​​peanuts has continued to increase, reaching 70 million mu, second only to soybeans and rapeseed, with a yield of up to 16 million tons. The yield, total output and export volume are all ranked first among the oil crops in the country, and it plays a vital role in ensuring the safety of edible oils in my country.

[0005] However, there is currently a widespread problem of excessive nitrogen fertilizer input in peanut fields, which results in low fertilizer utilization, high production costs, and a threat to the environment. It is imperative to reduce the use of nitrogen fertilizers.

[0006] Therefore, how to improve the nitrogen utilization efficiency of peanuts is an urgent problem that needs to be solved by those skilled in the art.

[0007] Summary of the Invention

[0008] In view of this, the object of the present invention is to provide a method for improving the nitrogen utilization efficiency of peanuts by applying molybdenum to the root zone, so as to solve the shortcomings of the prior art.

[0009] In order to achieve the above object, the present invention adopts the following technical solutions:

[0010] A method for improving nitrogen utilization efficiency of peanuts by applying molybdenum to the root zone, specifically comprising the following steps:

[0011] (1) Land preparation and fertilization

[0012] Select suitable land, evenly spread decomposed household organic fertilizer, nitrogen, phosphorus and potassium compound fertilizer and ammonium molybdate as base fertilizer, and plow and ridge;

[0013] (2) Seed selection and seed dressing

[0014] Choose peanut varieties that are early to mid-maturing, high-quality, disease-resistant, and stress-resistant. After sun-drying, peel the peanuts and select healthy, plump kernels as seeds. Use ammonium molybdate to mix the seeds or soak them in ammonium molybdate solution before sowing them at the right time.

[0015] (3) Field management

[0016] At the seedling stage and the flowering and needle-setting stage, use ammonium molybdate solution for foliage spraying;

[0017] (4) Harvest and storage

[0018] Harvest in time, dry and store.

[0019] Furthermore, in the above step (1), the application rate of decomposed household organic fertilizer is 2000-2500 kg / mu; the application rate of nitrogen, phosphorus and potassium compound fertilizer is 25-30 kg / mu; the application rate of ammonium molybdate is 20-50 g / mu; and the tillage depth is 20-30 cm.

[0020] Furthermore, in the above step (2), the fruit sun-drying time is 2-3 days; the seed dressing amount of ammonium molybdate is 2-5 g / kg; the mass percentage of the ammonium molybdate solution is 0.05%-0.1%; the seed soaking time is 8-16 hours; and the sowing depth is 3-7 cm.

[0021] Furthermore, in the above step (3), the mass percentage of the ammonium molybdate solution is 0.02%-0.1%; and the number of foliar sprayings is 2-3 times.

[0022] Furthermore, in the above-mentioned step (4), the timing of harvesting is: the above-ground plant basically stops growing, the middle and lower leaves fall off, the upper leaves turn yellow, the stems turn yellow, and the shells of most pods in the underground part become hard, with obvious reticulation and brown inner walls; and the pods are dried to a moisture content of less than 15%.

[0023] It can be seen from the above technical solution that compared with the prior art, the beneficial effects of the present invention are as follows:

[0024] 1. The present invention uses ammonium molybdate on peanuts before sowing, during sowing, in the seedling stage, and during the flowering and needle-setting stage. Molybdenum can participate in the carbon and nitrogen metabolism process in the plant body, increase the activity of nitrate reductase, and promote the plant's synthesis of nutrients such as amino acids and proteins. Most importantly, it can also improve the nitrogen fixation ability of peanuts, thereby improving the nitrogen utilization rate of peanuts.

[0025] 2. The molybdenum application method of the present invention can improve the root morphology of peanuts, enhance the photosynthesis capacity of leaves, increase the transfer of nitrogen to pods, increase the dry matter accumulation and yield of peanuts, thereby improving nitrogen absorption and utilization, and ultimately significantly increasing the per-acre yield of peanuts. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are merely embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying any creative work.

[0027] FIG1 is a schematic diagram of the structure of the experimental system for studying the microenvironment of peanut roots and pods;

[0028] Figure 2 is a structural diagram of the planting method.

[0029] Among them, 1-root growth box, 2-pod growth box, 21-seeding tube, 22-pod separation tube, 23-pod inner chamber, 24-pod outer chamber, 3-peanut pod, 4-peanut plant, 5-peanut root system, 6-ring-shaped sponge, 7-hanging protrusion. DETAILED DESCRIPTION

[0030] The following is a clear and complete description of the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of the present invention.

[0031] Example 1

[0032] The method for improving nitrogen utilization efficiency of peanuts by applying molybdenum to the root zone specifically comprises the following steps:

[0033] (1) Land preparation and fertilization

[0034] Select suitable land and evenly spread 2000kg of decomposed household organic fertilizer, 25kg of nitrogen, phosphorus and potassium compound fertilizer and 20g of ammonium molybdate per mu as base fertilizer, and plow and form ridges with a depth of 20cm.

[0035] (2) Seed selection and seed dressing

[0036] Choose peanut varieties that are early to mid-maturing, high-quality, disease-resistant, and stress-resistant. Sun-dry the peanuts for two days before shelling them. Select healthy, plump kernels as seeds. Mix the seeds with 2g of ammonium molybdate per kilogram and sow them at the appropriate time at a sowing depth of 3cm.

[0037] (3) Field management

[0038] At the seedling stage and the flowering and needle-setting stage, spray the leaves with 0.02% ammonium molybdate solution twice;

[0039] (4) Harvest and storage

[0040] The aboveground plants basically stop growing, the middle and lower leaves fall off, the upper leaves turn yellow, the stems turn yellow, and the shells of most pods in the underground part become hard, the reticulation is obvious, and the inner wall of the shell is brown; store them after drying to a moisture content of less than 15%.

[0041] Example 2

[0042] The method for improving nitrogen utilization efficiency of peanuts by applying molybdenum to the root zone specifically comprises the following steps:

[0043] (1) Land preparation and fertilization

[0044] Select suitable land and evenly spread 2200kg of decomposed household organic fertilizer, 28kg of nitrogen, phosphorus and potassium compound fertilizer and 35g of ammonium molybdate per mu as base fertilizer, and plow and form ridges with a depth of 30cm.

[0045] (2) Seed selection and seed dressing

[0046] Choose peanut varieties that are early to mid-maturing, high-quality, disease-resistant, and stress-resistant. Sun-dry the peanuts for three days before shelling them. Select healthy, plump kernels as seeds. Mix the seeds with 3g of ammonium molybdate per kilogram and sow them at the appropriate time at a sowing depth of 5cm.

[0047] (3) Field management

[0048] At the seedling stage and the flowering and needle-setting stage, spray the leaves with 0.06% ammonium molybdate solution three times respectively;

[0049] (4) Harvest and storage

[0050] The aboveground plants basically stop growing, the middle and lower leaves fall off, the upper leaves turn yellow, the stems turn yellow, and the shells of most pods in the underground part become hard, the reticulation is obvious, and the inner wall of the shell is brown; store them after drying to a moisture content of less than 15%.

[0051] Example 3

[0052] The method for improving nitrogen utilization efficiency of peanuts by applying molybdenum to the root zone specifically comprises the following steps:

[0053] (1) Land preparation and fertilization

[0054] Select suitable land and evenly spread 2500kg of decomposed household organic fertilizer, 30kg of nitrogen, phosphorus and potassium compound fertilizer and 50g of ammonium molybdate per mu as base fertilizer, and plow the land to 30cm to form ridges;

[0055] (2) Seed selection and seed dressing

[0056] Select peanut varieties that are early to mid-maturing, high-quality, disease-resistant, and stress-resistant. Sun-dry the peanuts for three days before shelling them. Select healthy, plump kernels as seeds and soak them in a 0.1% ammonium molybdate solution for 16 hours before sowing them at a depth of 7 cm.

[0057] (3) Field management

[0058] At the seedling stage and the flowering and needle-setting stage, spray the leaves with 0.1% ammonium molybdate solution three times respectively;

[0059] (4) Harvest and storage

[0060] The aboveground plants basically stop growing, the middle and lower leaves fall off, the upper leaves turn yellow, the stems turn yellow, and the shells of most pods in the underground part become hard, the reticulation is obvious, and the inner wall of the shell is brown; store them after drying to a moisture content of less than 15%.

[0061] Performance Testing

[0062] 1. Root zone molybdenum application improves nitrogen absorption and utilization in peanuts and its regulatory mechanism

[0063] 1 Materials and Methods

[0064] 1.1 Test location and materials

[0065] A random arrangement micro-plot positioning experiment was used. The peanut variety tested was the pearl bean type high oleic acid variety Yuhua 37. The soil type was sandy fluvo-aquic soil. The basic physical and chemical properties of the soil are shown in Table 1.

[0066] Table 1 Basic physical and chemical properties of soil

[0067] As shown in Table 1, the effective molybdenum content of the soil is 0.065 mg / kg, which is far less than the standard value of 0.2 mg / kg, indicating that it is molybdenum-deficient soil.

[0068] 1.2 Experimental design

[0069] Planting was carried out using the experimental system for studying the root system and pod microenvironment of peanuts as shown in Figure 1 and the planting method as shown in Figure 2 (the experimental system and planting method are both recorded in the invention patent of the Institute of Plant Nutrition and Resources Environment of Henan Academy of Agricultural Sciences, application number 202010490251.8, and application date 2020.06.02).

[0070] Four treatments were set up: R0P0: root zone (-Mo) + pod zone (-Mo); R Mo P Mo : Root zone (Mo) + pod zone (Mo); R Mo P0: root zone (Mo) + pod zone (-Mo); R0PMo Root zone (-Mo) + pod zone (Mo). Mo concentrations were set to 0 (i.e., soil background Mo content of 0.065 mg / kg) and 0.20 mg / kg, respectively, using analytically pure ammonium molybdate as the fertilizer source. Eight replicates were performed. Other fertilizer rates and field management practices remained consistent.

[0071] Urea (46% nitrogen) was used as the nitrogen fertilizer. Analytically pure (AR) potassium dihydrogen phosphate (52% P₂O, 34% K₂O) and potassium sulfate (54% K₂O) were used at rates of 8 kg / mu and 6 kg / mu, respectively. Each pot was filled with 17 kg of soil for the root zone and 8 kg for the pod zone, for a total of 25 kg. Nitrogen was applied at 5.0 g and 4.2 g, P₂O at 3.3 g, and K₂O at 2.5 g.

[0072] 1.3 Sample collection and analysis

[0073] During the peanut flowering stage (August 5, 2022), three representative pots (three plants) of peanuts were selected from each treatment, and photosynthetic parameters (net photosynthetic rate (Pn), stomatal conductance (Gs), intercellular CO2 concentration (Ci), and transpiration rate (Tr, SPAD)) were measured using a portable photosynthetic meter. Intact peanut roots were removed from the culture pots and gently rinsed with running water. During rinsing, a 100-mesh sieve was placed under the roots to prevent any loose roots from being washed away. After rinsing, the root surface was dried and digital images were obtained using an EPSON Perfection V800 / V850 scanner. Images were analyzed using the WinRHIZO Root Analysis System (Regent, Canada) to determine total root length, root surface area, root volume, and number of root tips. Plant samples were collected from various locations to determine nitrogen content. Plants were tested, weighed, and yielded at harvest time.

[0074] 1.4 Data Processing and Analysis

[0075] Data were organized using Microsoft Excel 2013.

[0076] Plant nutrient accumulation (g / pot) = nutrient content × plant dry matter weight;

[0077] Partial productivity of nitrogen fertilizer (kg / kg) = yield in nitrogen fertilizer application area / amount of nitrogen fertilizer used;

[0078] Nitrogen use efficiency (kg / kg) = pod weight / total nitrogen accumulation;

[0079] Nitrogen dry matter production efficiency (kg / kg) = dry matter accumulation / total nitrogen accumulation;

[0080] Nitrogen use efficiency (NRE, %) = total nitrogen accumulation of the whole plant at harvest time / amount of nitrogen fertilizer applied × 100.

[0081] 2 Results and Analysis

[0082] 2.1 Effects of exogenous molybdenum on peanut growth

[0083] Table 2 Effects of molybdenum on biomass of different parts of peanut

[0084] As shown in Table 2, the three molybdenum application methods increased the dry matter mass of the root system and aboveground parts of peanuts at the flowering and mature stages. Mo P Mo 、R Mo P0, R0P Mo Root dry weights in the ROP0 treatments were, on average, 55.94%, 38.68%, and 19.92% higher than those in the R0P0 treatment; aboveground dry weights were, on average, 55.30%, 29.88%, and 14.47% higher than those in the R0P0 treatment; and pod weights were, on average, 64.69%, 30.27%, and 7.08% higher than those in the R0P0 treatment. These results indicate that molybdenum application promotes dry matter accumulation in peanuts, with root application being particularly effective. Therefore, root application of molybdenum is a suitable nitrogen and molybdenum application method for promoting peanut growth and yield.

[0085] 2.2 Effects of exogenous molybdenum on nitrogen and molybdenum absorption in peanuts

[0086] Table 3 Effect of molybdenum on nitrogen and molybdenum absorption in different parts of peanuts

[0087] As shown in Table 3, compared with no Mo application, Mo application significantly increased the nitrogen accumulation in roots and aboveground parts. Mo P Mo and R Mo The nitrogen accumulation in the roots and aboveground parts of the P0 treatment was higher than that in the pod area treated with molybdenum alone (R0P Mo ), 50.89% and 33.13%, and 41.00% and 19.21% higher, respectively. This suggests that applying molybdenum to the root zone can better promote nitrogen absorption and utilization in peanuts. Since the peanut pod layer is generally distributed within the 0-15cm soil layer, while the root system is mainly concentrated in the 20-30cm soil layer, from the perspective of "using molybdenum to promote nitrogen utilization," when applying molybdenum fertilizer to the soil, it is recommended that the fertilizer be applied deep into the root zone.

[0088] During the peanut maturity period, molybdenum application significantly increased nitrogen accumulation in the aboveground parts and pods, but had little effect on nitrogen accumulation in the roots. Mo P Mo Processing is the highest, followed by R MoP0 processing, R0P Mo Processing minimum. R0P0, R Mo P Mo 、R0P Mo The transfer amounts of nitrogen from the aboveground parts to the pods in the R0 and R0P0 treatments were 150.39, 298.71, 247.80 and 209.76 mg / pot, respectively, indicating that molybdenum application promoted the transfer of nitrogen from the aboveground parts to the pods in peanuts.

[0089] 2.3 Effect of exogenous molybdenum on nitrogen utilization in peanuts

[0090] Table 4 Effects of molybdenum application on nitrogen utilization in peanut

[0091] As shown in Table 4, molybdenum application improved the nitrogen utilization of peanuts. Compared with R0P0, R Mo P Mo 、R Mo P0 and R0P Mo The nitrogen partial productivity of peanuts treated with the above treatments was 64.69%, 30.27% and 7.08% higher, the nitrogen pod production efficiency was 20.03%, 13.11% and 7.52% higher, the nitrogen dry matter production efficiency was 59.00%, 27.58% and 8.96% higher, and the nitrogen fertilizer use efficiency was 37.20%, 15.17% and 0.42% higher. Mo P Mo and R Mo Peanuts treated with P0 had a stronger ability to utilize nitrogen, and applying molybdenum to the root zone was the best way to promote efficient nitrogen utilization in peanuts.

[0092] 2.4 Effects of exogenous molybdenum on peanut root morphology

[0093] Table 5 Effects of molybdenum on peanut root morphology

[0094] As shown in Table 5, applying molybdenum can improve various morphological indices of peanut root system. Mo P Mo 、R Mo P0 and R0P Mo Compared with no molybdenum application (ROP0), the total root length under the three molybdenum application methods increased by an average of 119.28%, 75.82%, and 30.07%, respectively. The total root surface area increased by an average of 58.46%, 46.74%, and 2.97%, respectively. The total root volume increased by an average of 56.55%, 23.52%, and 10.08%, respectively. The root diameter decreased by an average of 24.68%, 21.44%, and 11.02%, respectively. These results indicate that all three molybdenum application methods promoted peanut root growth to a certain extent, with the treatment that applied molybdenum simultaneously to the root and pod regions showing the best effect.

[0095] 2.5 Effects of exogenous molybdenum on peanut photosynthesis

[0096] Table 6 Effect of molybdenum on peanut photosynthesis

[0097] As shown in Table 6, applying molybdenum can improve the photosynthetic capacity of peanuts. Mo P Mo 、R Mo P0 and R0P Mo Compared with no molybdenum application (ROP0), peanut leaf photosynthetic rates under the three molybdenum application methods increased by an average of 76.08%, 40.87%, and 13.85%, respectively. Transpiration rates increased by an average of 94.74%, 50.42%, and 27.15%, respectively. Stomatal conductance increased by an average of 172.71%, 96.79%, and 40.16%, respectively. Intercellular CO₂ concentrations increased by an average of 45.13%, 27.30%, and 19.79%, respectively. These results indicate that all three molybdenum application methods enhanced peanut photosynthetic characteristics to a certain extent, with the effect being best achieved when molybdenum was applied simultaneously to the root and pod regions.

[0098] 3 Conclusion

[0099] In summary, the molybdenum application method of the present invention can improve nitrogen absorption and utilization by improving peanut root morphology, enhancing leaf photosynthesis, increasing nitrogen transfer to pods, and increasing peanut dry matter accumulation and yield. Compared with different molybdenum application methods, simultaneous molybdenum application to the root and pod zones and molybdenum application to the root zone alone are more effective in improving nitrogen utilization and yield than molybdenum application to the pod zone. It is recommended that molybdenum be applied deep into the root zone when applying soil.

[0100] 2. Peanut Index

[0101] The peanuts in Example 2, which differed only in that ammonium molybdate was not applied as base fertilizer in step (1), were used as a comparative example. The emergence rate, plant traits, yield and yield increase rate of the peanuts in Examples 1-3 and the comparative example were observed, counted and calculated.

[0102] The results are shown in Table 7.

[0103] Table 7 Peanut indexes of Examples 1-3 and Comparative Examples

[0104] As shown in Table 7, compared with the peanuts without ammonium molybdate as base fertilizer in step (1), the emergence rate, plant traits and yield of the peanuts in Examples 1-3 of the present invention were significantly improved, with the highest yield increase rate reaching 18.53%.

[0105] The above description of the disclosed embodiments is intended to enable one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be readily apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not limited to the embodiments shown herein but is intended to conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for improving nitrogen utilization efficiency of peanuts by applying molybdenum to the root zone, characterized in that: The specific steps include: (1) Land preparation and fertilization Choose suitable land, evenly spread decomposed household organic fertilizer, nitrogen, phosphorus and potassium compound fertilizer and ammonium molybdate as base fertilizer, and till and ridge the land; (2) Seed selection and seed mixing Choose early-to-mid-maturing, high-quality, disease-resistant and stress-resistant peanut varieties, peel the shells after sun drying, select healthy and plump kernels as seeds, and mix the seeds with ammonium molybdate or soak the seeds with ammonium molybdate solution before sowing at the right time; (3) Field management At the seedling stage and the flowering and needle-setting stage, use ammonium molybdate solution for foliar spraying; (4) Harvest and storage Harvest at the right time, dry and store.

2. The method for improving nitrogen utilization efficiency of peanuts by applying molybdenum to the root zone according to claim 1, characterized in that: In step (1), the application amount of the decomposed household organic fertilizer is 2000-2500kg / mu; the application amount of the nitrogen, phosphorus and potassium compound fertilizer is 25-30kg / mu; and the application amount of the ammonium molybdate is 20-50g / mu.

3. The method for improving nitrogen utilization efficiency of peanuts by applying molybdenum to the root zone according to claim 1, characterized in that: In step (1), the tillage depth is 20-30 cm.

4. The method for improving nitrogen utilization efficiency of peanuts by applying molybdenum to the root zone according to claim 1, characterized in that: In step (2), the fruit is dried in the sun for 2-3 days.

5. The method for improving nitrogen utilization efficiency of peanuts by applying molybdenum to the root zone according to claim 1, characterized in that: In step (2), the seed dressing amount of ammonium molybdate is 2-5 g / kg; the mass percentage of the ammonium molybdate solution is 0.05%-0.1%; and the seed soaking time is 8-16 hours.

6. The method for improving nitrogen utilization efficiency of peanuts by applying molybdenum to the root zone according to claim 1, characterized in that: In step (2), the sowing depth is 3-7 cm.

7. The method for improving nitrogen utilization efficiency of peanuts by applying molybdenum to the root zone according to claim 1, characterized in that: In step (3), the mass percentage of the ammonium molybdate solution is 0.02%-0.1%.

8. The method for improving nitrogen utilization efficiency of peanuts by applying molybdenum to the root zone according to claim 1, characterized in that: In step (3), the foliar spraying is performed 2-3 times.

9. The method for improving nitrogen utilization efficiency of peanuts by applying molybdenum to the root zone according to claim 1, characterized in that: In step (4), the timing of harvesting is: the aboveground plant basically stops growing, the middle and lower leaves fall off, the upper leaves turn yellow, the stems turn yellow, and the shells of most pods in the underground part become hard, with obvious reticular patterns and brown inner walls of the shells.

10. The method for improving nitrogen utilization efficiency of peanuts by applying molybdenum to the root zone according to claim 1, characterized in that: In step (4), the drying is performed until the moisture content is below 15%.

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