Paddy rice saline-alkaline tolerance identification platform capable of controlling saline-alkaline gradient and use method

Abstract

The invention discloses a rice saline-alkaline tolerance identification platform capable of controlling saline-alkaline gradient and a use method, and belongs to the field of agricultural science, the platform comprises a greenhouse, culture pits are dug in the greenhouse, culture containers are placed in the pits, non-saline-alkaline soil, mild saline-alkaline soil, moderate saline-alkaline soil and severe saline-alkaline soil are respectively filled, and rice seedling raising, transplanting and field management are carried out. After harvesting, investigating the yield and composition factors of the rice so as to identify the saline-alkaline resistance of different varieties. According to the invention, the growth environment of rice under different saline-alkaline gradients can be accurately simulated, and a scientific and repeatable experimental platform is provided for saline-alkaline tolerance identification of rice varieties.

Description

Technical Field

[0001] The present invention relates to the field of agricultural science and technology, and more specifically to a platform for identifying the salt and alkali tolerance of rice with a controllable salt and alkali gradient and its usage method. Background Art

[0002] The soda saline-alkali land in Northeast China is one of the three major saline-alkali land distribution areas in the world, with a total area of 5 million hectares, and the area of moderately and severely soda-salinized land accounts for 67.4%. The soil salt composition of this type of saline-alkali land is mainly soda (Na 2 CO 3 ), and the alkalization process accompanies the soda salinization process. Therefore, soda saline-alkali soil has different degrees of salinization and alkalization characteristics. Salt and alkali stress is one of the main limiting factors affecting rice growth and yield. Scientific research on the growth differences of different rice varieties in saline-alkali environments is of great significance for cultivating salt and alkali tolerant rice varieties and increasing grain yields in saline-alkali land. At present, most salt and alkali stress experimental platforms have deficiencies in simulating gradient stress and controllable environments, and it is difficult to meet the water layer stability and environmental control required for the long-term growth of rice. Summary of the Invention

[0003] In view of this, the present invention provides an experimental platform for the salt and alkali tolerance of rice in a controllable salt and alkali gradient environment. By setting soils with different salt and alkali stress gradients and combining with the growth characteristics of rice, a controllable simulated saline-alkali environment is provided to scientifically study the salt and alkali tolerance of different rice varieties, providing an important guarantee for grain production in saline-alkali land.

[0004] To achieve the above object, the present invention adopts the following technical solutions: First of all, the present invention provides an experimental platform for the salt and alkali tolerance of rice with a controllable salt and alkali gradient, including a greenhouse shed, and the top of the greenhouse shed is covered with a plastic film; A plurality of culture pits are dug on the ground inside the greenhouse shed; culture containers are placed in the culture pits.

[0005] Preferably, the greenhouse shed is a high-arch greenhouse shed, the center of the shed roof is 3 - 4.5 m high from the ground, and a 40 - 60 mesh nylon net is arranged 1 m above the ground inside the shed roof.

[0006] Preferably, the culture pit has a diameter of 30 cm, a depth of 35 - 40 cm, and a distance of 60 cm between pits.

[0007] Preferably, the culture container is a non-porous culture bucket.

[0008] The present invention also provides a usage method for the experimental platform as described in the above technical solution, including the following steps: Step 1: Establish a greenhouse shed Select an area with flat terrain and good drainage, clear weeds and gravel, ensure the ground is level, and build a greenhouse shed; Step 2: Dig cultivation pits in the greenhouse shed and place cultivation containers Mark the positions of the cultivation pits in the greenhouse shed according to the pit spacing, dig pits according to the preset cultivation pit specifications, with vertical pit walls and flat pit bottoms, and then vertically place the cultivation containers into the cultivation pits. The mouths of the cultivation containers are level with the ground, and the surrounding soil is filled and compacted; Step 3: Preparation and filling of soda saline-alkali gradient soil (3.1) Collect non-saline control soil with a pH of 7.0 - 7.3 from a non-saline rice experimental field, and collect slightly saline soil from a slightly saline rice field with a pH of 7.9 - 8.1. The soil sampling depth is 0 - 20 cm for both; (3.2) Naturally dry the two types of soil taken in step (3.1), remove impurities, mechanically crush them, and sieve them through a 0.5 cm sieve; (3.3) Based on the slightly saline soil, prepare moderately saline soil and severely saline soil to obtain four saline-alkali gradient soils: non-saline soil, slightly saline soil, moderately saline soil, and severely saline soil; (3.4) Fill the cultivation containers with different gradients of soil respectively, so that the height of the soil in the cultivation container is 5 cm from the top end of the cultivation container; Step 4: Fertilization and watering in the buckets Evenly sprinkle compound fertilizer on the soil surface in each cultivation container, and then conduct the first watering. The water level is controlled at 0.5 - 1 cm from the edge of the cultivation container. After adding water, let the soil soak for 2 - 3 h. After soaking, stir the soil evenly, and then let it stand for more than 12 h; Step 5: Transplanting rice Select rice seedlings of different rice varieties with a seedling age of more than 35 days, consistent leaf age, strong roots, and no pests and diseases for transplantation. Transplant the same number of rice seedlings into each cultivation container, with the roots vertically inserted into the soil to a depth of 2 - 3 cm; Step 6: Field management In the initial stage of transplantation, the water level in the cultivation container is 0.5 - 1 cm from the edge of the cultivation container; topdress urea 4 - 5 weeks after transplantation; Step 7: Harvest rice and investigate the yield components Harvest the rice after it matures, and investigate the yield and its components of the rice in each cultivation container after harvest.

[0009] Preferably, the preparation of moderately saline soil and severely saline soil in step (3.3) includes the following steps: Based on the slightly saline soil, weigh Na according to 0.1 - 0.15% of its soil weight 2 CO 3, dissolve it in water and then evenly add it to the slightly saline-alkali soil. Mix well, let the mixed soil stand for 2 days, and wait for the physical and chemical properties of the soil to stabilize to obtain moderately saline-alkali soil; Based on the slightly saline-alkali soil, weigh Na according to 0.4 - 0.45% of its soil weight 2 CO 3 , dissolve it in water and then evenly add it to the slightly saline-alkali soil. Mix well, let the mixed soil stand for 2 days, and wait for the physical and chemical properties of the soil to stabilize to obtain moderately saline-alkali soil.

[0010] Preferably, the compound fertilizer described in step four is a 18 - 18 - 18 compound fertilizer.

[0011] Preferably, the constituent factors described in step seven include the number of effective panicles per plant, the number of grains per panicle, the seed setting rate, the 1000 - grain weight, as well as the plant height, tiller number, leaf number and root growth status of the rice plant.

[0012] From the above technical solutions, it can be seen that compared with the prior art, the present invention discloses a rice salt - alkali tolerance identification platform and its usage method under a controllable salt - alkali gradient environment, having the following beneficial effects: The present invention can accurately simulate the rice growth environment under different salt - alkali gradients, providing a scientific and reproducible experimental platform for the identification of rice variety salt - alkali tolerance. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following drawings are only the embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained according to the provided drawings without creative efforts.

[0014] Figure 1 It is the overall structure diagram and application diagram of the rice salt - alkali tolerance identification platform under a controllable salt - alkali gradient environment; Figure 2 It is the verification results of different rice varieties under the salt - alkali identification platform; Figure 3 It is the growth conditions of different rice varieties under different salt - alkali gradients. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0015] The following will clearly and completely describe the technical solutions of the present invention in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of them. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0016] As attached Figure 1 As described above, the experimental platform for rice salt tolerance under a controllable saline-alkali gradient environment includes a greenhouse shed. The top of the greenhouse shed is covered with a plastic film. Multiple cultivation pits are dug on the ground inside the greenhouse shed, and cultivation containers are placed in the cultivation pits. The greenhouse shed is a high-arched greenhouse shed. The height from the center of the shed roof to the ground is 3 - 4.5 m, and a 40 - 60 mesh nylon net is set at a height of 1 m from the ground inside the shed roof. The cultivation pits have a diameter of 30 cm, a depth of 35 - 40 cm, and a distance of 60 cm between the pits. The cultivation containers are non-porous cultivation buckets.

[0017] The usage method of the experimental platform for rice salt tolerance under a controllable saline-alkali gradient environment includes the following steps: Step 1: Establish a high-arched ventilation and rain-sheltering shed Select an area with flat terrain and good drainage, clean weeds and gravel, and ensure the ground is flat. Use corrosion-resistant galvanized steel pipes or aluminum alloy pipes to build arch frames according to the designed height (3 - 4.5 m) and spacing (1.0 - 1.5 m), and reinforce them with bolts or welding to ensure the structure is stable and wind-resistant. Install a 40 - 60 mesh nylon net at a height of 1.0 - 1.5 m below the arch shed, tighten and fix it to ensure smooth ventilation and prevent rainwater from seeping in. Uniformly cover the top with a high-transparency and weather-resistant plastic film, and fix it with clamps or film pressing wires to ensure good sealing. Set adjustable ventilation openings at both ends or on the sides to ensure air circulation inside the shed.

[0018] Step 2: Dig soil pits in the rain-sheltering shed and bury water buckets Inside the rain-sheltering shed, select a position 1 m below the nylon net as a reference, mark the positions of the soil pits, and ensure that the left-right and front-back distances between the pits are both 60 cm to avoid plant shading. Dig according to the standards of a diameter of 30 cm and a depth of 35 - 40 cm with a shovel or a pit digger to ensure that the pit walls are vertical and the pit bottoms are flat. Vertically place the water buckets without drainage holes into the pits, with the bucket mouths level with the ground, and fill the surrounding soil and compact it to prevent the bucket bodies from loosening or tilting. Finally, check the distribution and stability of the pit positions and the buckets to ensure uniform arrangement, and make preparations for subsequent soil filling and rice planting.

[0019] Step 3: Prepare the soda saline-alkali gradient soil First, collect non-saline control soil (pH 7.0 - 7.3) from a non-saline rice experimental field, and collect slightly saline soil from a slightly saline rice experimental field with a pH value of 7.9 - 8.1. The soil sampling depth is 0 - 20 cm for both. Let the two types of soil dry naturally, remove impurities, and use a machine to crush them and then pass through a sieve with a pore size of 0.5 cm for standby.

[0020] Next, based on the slightly saline soil, weigh chemical pure Na 2 CO 3, dissolve it separately in water with the same weight as the soil to prepare a solution, and then evenly pour it into the slightly saline-alkali soil and mix well. Let the mixed soil stand for 2 days until the physical and chemical properties of the soil are stable.

[0021] Finally, put the soils with different gradients into buckets without drainage holes to obtain the following four saline-alkali gradients: Group T0 (control group): non-saline-alkali soil; Group T1 (slightly saline-alkali): T2 (moderately saline-alkali soil): add 0.1 - 0.15% of Na 2 CO 3 solution to the soil in Group T1; Group T3 (severely saline-alkali): add 0.4 - 0.45% of Na 2 CO 3 solution to the soil in Group T1. Put the soils with four different gradients into the buckets described in Step 2, with 15 - 17 kg filled in each bucket. At this time, the height of the soil in the bucket is 5 cm away from the top of the bucket.

[0022] Step Four: Fertilization and watering in the bucket Evenly sprinkle 5 g of agricultural compound fertilizer (Stanley, 18 - 18 - 18) on the soil surface in each bucket, and then conduct the first watering. Control the water level at 0.5 - 1 cm from the edge of the bucket to ensure sufficient water without overflowing outside the bucket. After adding water, let the soil soak for 2 - 3 h to soften the soil structure, promote the uniform penetration of water into each layer of the soil in the bucket, enhance the water-holding capacity and nutrient absorption capacity of the soil. After soaking, use a wooden stick or other suitable tools to stir the soil in the bucket evenly to ensure full integration of water and soil, eliminate possible hard lumps and air gaps, form a uniform soil structure, and optimize the root growth environment. After stirring, let the soil in the bucket stand for more than 12 hours to allow the water and soil to settle naturally, achieving a balanced distribution of water, nutrients, and soil particles, and creating a stable and suitable growth environment for subsequent rice seedling raising and transplanting.

[0023] Step Five: Rice transplanting Select rice seedlings of different rice varieties with a seedling age of more than 35 days, consistent leaf age, strong roots, and no pests and diseases for transplanting. Transplant 4 holes evenly in each bucket, with 2 rice seedlings planted in each hole. Insert the roots vertically into the soil, with the depth controlled at 2 - 3 cm to avoid being too deep or too shallow. After transplanting, gently compact the surrounding soil to ensure close contact between the roots and the soil, preventing the rice seedlings from shaking or lodging.

[0024] Step Six: Field management In the initial stage of transplantation, keep the water layer in the bucket stable, and control the water level at 0.5 - 1 cm from the bucket edge to prevent excessive or insufficient water, avoid salt accumulation around the roots, and affect the growth of rice seedlings. Four to five weeks after transplantation, add 1 g of urea to each bucket to ensure nutrient supply, promote rapid tillering and root development of rice seedlings. Regularly check the water level in the bucket, maintain a stable water layer depth, and prevent drought or waterlogging. Remove weeds in a timely manner to reduce nutrient consumption, observe the growth status of rice seedlings, pay attention to leaf color and root activity, and prevent and control pests and diseases in a timely manner.

[0025] Step Seven: Harvest rice and investigate the yield components At the mature stage of rice, choose a sunny day for harvesting to ensure that the rice plants are fully mature and have an appropriate moisture content. After harvesting, investigate the yield and its components of the rice in each bucket, mainly including the following indicators: the number of effective panicles per plant, the number of grains per panicle, the seed setting rate, the 1000-grain weight, etc. At the same time, record the plant height, tiller number, leaf number, and root growth status of the rice plants, comprehensively analyze the growth performance and yield component characteristics of rice under different saline-alkali gradients, and provide a scientific basis and data support for screening saline-alkali tolerant rice varieties.

[0026] The following uses specific implementation methods for verification: Example 1: Verify using the above method. The depth of the cultivation pit is 35 cm, the proportion of Na 2 CO 3 in T2 is 0.10%, the proportion of Na 2 CO 3 in T3 is 0.45%. In Step Four, control the water level at 1 cm from the bucket edge. In Step Five, select 40-day-old rice seedlings, and in Step Six, the additional urea is 0.8 g.

[0027] Experimental Example This experiment was carried out from April to October 2024, using rice varieties such as Suijing 124, Suijing 139, Suijing 141, Beihe 6, Jijing 336, Jijing 855, Zhongbao 8 as the research objects, and using the specific method of Example 1 for the experiment. The specific results are shown in Table 1 and Figures 2-3 as follows.

[0028] As Figure 2 and Figure 3 shown, the pH values of the soil saline-alkali gradients T0, T1, T2, and T3 groups are 7.1, 8.1, 8.6, and 9.5 respectively, and the electrical conductivities are 0.10, 0.20, 0.60, and 0.80 mS / cm respectively, meeting the non-saline-alkali, mild, moderate, and severe saline-alkali gradients. The salt tolerance of seven commonly used rice varieties in Northeast China was studied under this saline-alkali gradient.

[0029] Except for the significant difference in the yield per pot of the 7 rice varieties (lines) under T0 (non-saline-alkali) and T1 (mild saline-alkali stress), there was no significant difference in the other 6 varieties, indicating that mild saline-alkali stress had little effect on the growth and yield of rice. However, there were extremely significant differences in the yields of the 7 rice varieties (lines) under T2 (moderate saline-alkali stress) and T3 (severe saline-alkali stress), as well as compared with T0 (non-saline-alkali) and T1 (mild saline-alkali stress), showing an obvious downward trend, and the differences between varieties were very obvious.

[0030] Table 1 Comparison of rice yields of different rice varieties under saline-alkali stress As can be seen from Table 1, according to the yield retention rate of each rice variety (line) under T3 severe saline-alkali stress and T0 non-saline-alkali stress, the order of salt and alkali tolerance of the 7 identified rice varieties (lines) from strong to weak is: Jijing 336 > Zhongbao 8 > Jijing 855 > Suijing 139 > Suijing 124 > Suijing 141 > Beihe 6. According to the above principle, in this identification, Jijing 336 (yield retention rate 29.1%), Zhongbao 8 (yield retention rate 26.1%), Jijing 855 (yield retention rate 25.3%), and Suijing 139 (yield retention rate 25.3%) were defined as rice varieties with strong salt and alkali tolerance; Suijing 124 (yield retention rate 20.8%), Suijing 141 (yield retention rate 20.2%), and Beihe 6 (yield retention rate 20.2%) were defined as rice varieties with medium salt and alkali tolerance.

[0031] The various embodiments in this specification are described in a progressive manner. Each embodiment focuses on the differences from other embodiments. For the same or similar parts between the various embodiments, reference can be made to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and reference can be made to the description of the method part for the relevant parts.

[0032] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be obvious to those skilled in the art. The general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to these embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A rice salt-alkali tolerance experimental platform with controllable salt-alkali gradient, characterized in that: It comprises a greenhouse shed, the top of which is covered with a plastic film; A plurality of culture pits are dug on the ground in the greenhouse; culture containers are placed in the culture pits.

2. The rice salt-alkali tolerance experimental platform with controllable salt-alkali gradient according to claim 1, characterized in that: The greenhouse is a high-arch greenhouse, the center of the roof is 3-4.5m above the ground, and a 40-60 mesh nylon net is set inside the roof at a height of 1m from the ground.

3. The rice salt-alkali tolerance experimental platform with controllable salt-alkali gradient according to claim 1, characterized in that: The culture pit has a diameter of 30 cm, a depth of 35-40 cm, and a distance between pits of 60 cm.

4. The rice salt-alkali tolerance experimental platform with controllable salt-alkali gradient according to claim 1, characterized in that: The culture container is a non-porous culture barrel.

5. A method for using the experimental platform according to any one of claims 1 to 4, characterized in that: The following steps are involved: Step 1: Build a greenhouse Choose a flat, well-drained area, clear weeds and gravel, make sure the ground is level, and build a greenhouse; Step 2: Dig a culture pit in the greenhouse and place the culture container Mark the position of the culture pit in the greenhouse according to the pit distance, dig the pit according to the preset culture pit specifications, make the pit wall vertical and the pit bottom flat, then put the culture container vertically into the culture pit, make the mouth of the culture container level with the ground, and fill the surrounding soil and compact it; Step 3: Preparation and filling of soda saline-alkali gradient soil (3.1) Non-saline control soil with a pH of 7.0-7.3 was collected from non-salinized rice experimental fields, and slightly saline soil with a pH of 7.9-8.1 was collected from slightly saline rice fields. The soil sampling depth was 0-20 cm. (3.2) The two soils obtained in step (3.1) were naturally dried, impurities were removed, and mechanically crushed and passed through a 0.5 cm sieve; (3.3) Based on the light saline-alkali soil, moderate saline-alkali soil and severe saline-alkali soil were configured to obtain four types of saline-alkali gradient soils: non-saline-alkali soil, light saline-alkali soil, moderate saline-alkali soil and severe saline-alkali soil; (3.4) Place soils of different gradients into culture containers respectively, so that the height of the soil in the culture container is 5 cm from the top of the culture container; Step 4: Fertilizing and watering in the bucket Evenly sprinkle compound fertilizer on the soil surface of each culture container, then water it for the first time, and control the water level at 0.5-1cm away from the edge of the culture container. After adding water, let the soil fully soak for 2-3 hours. After soaking, stir the soil evenly and let it stand for more than 12 hours. Step 5: Rice transplanting Select rice seedlings of different rice varieties that are over 35 days old, have the same leaf age, have a strong root system and are free of pests and diseases for transplanting. Transplant the same number of rice seedlings into each culture container, with the root system vertically inserted into the soil at a depth of 2-3 cm; Step 6: Field Management At the beginning of transplanting, the water level in the culture container should be 0.5-1cm away from the edge of the culture container; urea should be applied 4-5 weeks after transplanting; Step 7: Harvest rice and investigate yield components The rice is harvested when it matures, and the yield and composition factors of the rice in each culture container are investigated after harvesting.

6. The method of use according to claim 5, characterized in that: The preparation of moderately saline-alkali soil and severely saline-alkali soil in step (3.3) includes the following steps: Based on slightly saline-alkali soil, weigh 0.1-0.15% of the weight of the soil Na2CO3, dissolve it in water and evenly add it to the slightly saline-alkali soil, mix it thoroughly, and let the mixed soil stand for 2 days until the physical and chemical properties of the soil are stable, and then obtain moderate saline-alkali soil; Based on slightly saline-alkali soil, weigh Na2CO3 according to 0.4-0.45% of the soil weight, dissolve it in water and evenly add it to the slightly saline-alkali soil, mix it thoroughly, let the mixed soil stand for 2 days, and after the physical and chemical properties of the soil are stable, moderate saline-alkali soil is obtained.

7. The method of use according to claim 5, characterized in that: The compound fertilizer described in step 4 is an 18-18-18 compound fertilizer.

8. The method of use according to claim 5, characterized in that: The constituent factors described in step seven include the number of effective ears per plant, the number of grains per ear, the fruit setting rate, the thousand-grain weight, and the plant height, the number of tillers, the number of leaves and the root growth status of the rice plant.

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