Cultivation method for remarkably improving salt tolerance of rice in salinized land

Abstract

The invention relates to the technical field of crop planting, in particular to a cultivation method for remarkably improving salt tolerance of rice in salinized land, which comprises the steps of area selection, salt leaching and discharging and soil conditioner application, variety selection, transplanting time and transplanting mode selection, fertilizer application, water management and field management. From the perspective of efficient utilization of industrial solid wastes and full play of maximum benefits of nitrogen resources, the cultivation method for improving soil and efficient utilization of nitrogen resources under the background of a coastal salinized farmland area so as to improve the salt tolerance of the rice in the salinized land is determined; and certain technical guidance is provided for rice planting in coastal salinized areas.

Description

Technical Field

[0001] The invention relates to the technical field of crop planting, and in particular to a cultivation method for significantly improving the salt tolerance of rice in saline land. Background Art

[0002] Natural clinoptilolite will produce a large amount of clinoptilolite waste and scraps in industrial production. Clinoptilolite is a natural mineral resource with multiple uses. If it is treated as waste, it will cause a large waste of resources. By recycling and reusing clinoptilolite waste, natural resources can be saved. Clinoptilolite has a huge specific surface area and has the advantages of high quality and low price in improving salt. Secondly, its rich multi-voids and unique ionic structure should have unique advantages in nitrogen fixation. The clinoptilolite waste is crushed to form granular clinoptilolite with a particle size of 0.2-0.4 cm. The granular clinoptilolite with a particle size of 0.2-0.4 cm is moderate in size and can better combine with soil particles to form a stable soil structure. At the same time, the granular clinoptilolite with a particle size of 0.2-0.4 cm can both increase the porosity of the soil and maintain the stability of the soil. At present, the research on improving the salt tolerance of rice in saline land mostly adopts the method of applying soil conditioners. For example, the soil conditioner used in patent CN110463398B includes main ingredient A, fermentation medium A, zeolite powder, bentonite, ammonium sulfate, and superphosphate. Although natural zeolite powder is used, the effect and role of zeolite powder in the soil conditioner cannot be confirmed. In addition, after using the soil conditioner, basal fertilizer needs to be applied, and topdressing needs to be applied during the field soaking period, the greening and tillering period, the filling period, and the booting period. The frequent fertilization increases the labor input. The selection and use of soil conditioners ignores ecological balance, recycling of industrial solid waste and efficient utilization of nitrogen resources; the present invention is based on the geographical location, meteorological conditions, light and heat resources, and basic physical and chemical conditions of soil in Leyi Village, Liguo Town, Ledong Li Autonomous County, Hainan Province, and from the perspective of efficient utilization of industrial solid waste and full utilization of nitrogen resources to maximize the benefits, a cultivation method for improving soil and efficient utilization of nitrogen resources in the context of coastal saline farmland areas is determined, providing certain technical guidance for rice cultivation in coastal saline areas. Summary of the invention

[0003] The main purpose of the present invention is to provide a cultivation method for significantly improving the salt tolerance of rice in saline land, and to solve the problem that the use of soil conditioners in the prior art ignores ecological balance, the recycling of industrial solid waste, and the efficient utilization of soil conditioners and nitrogen resources.

[0004] To achieve the above object, the technical solution adopted by the present invention is: A cultivation method for significantly improving the salt tolerance of rice in saline land, comprising the following steps: (1) Area selection: Select a site adjacent to the sea, with a large area of ​​saline land formed by seawater backflow, which can provide farmland with different degrees of salinization, and has rich meteorological conditions and light and heat resources to meet the basic experimental conditions; (2) Salt washing and drainage and application of soil conditioners: First, build a 20 cm earth ridge around the farmland, dry the farmland in the first two days, irrigate the farmland on the third day, drain the water in the farmland one day later, and irrigate the farmland on the second day. Repeat this process several times to keep the salt content in the soil no higher than 5‰ w / v, and the basic soil salinity is controlled at around 3‰ w / v; sprinkle 0.2-0.4 cm granular clinoptilolite as a soil conditioner during rotary tillage; Clinoptilolite has a huge specific surface area and has the advantages of high quality and low price in improving salt. Secondly, its rich multi-pores and unique ionic structure should have unique advantages in nitrogen fixation. Compared with large-particle clinoptilolite, granular clinoptilolite with a particle size of 0.2-0.4cm has a moderate particle size and can better combine with soil particles to form a stable soil structure. Compared with small-particle clinoptilolite, granular clinoptilolite with a particle size of 0.2-0.4cm can both increase the porosity of the soil and maintain the stability of the soil, providing a better environment for rice growth. (3) Variety selection: Based on the high temperature weather and high soil salinity in the planting area, select rice varieties that are resistant to high temperatures and salt; (4) Transplanting time and method: When the white roots of rice seedlings gradually emerge and the layers increase, it is the best time to transplant. On this basis, if the weather is hot, the transplanting time of the seedlings should be advanced. Otherwise, the transplanting time should be delayed. When transplanting, the seedlings should be transplanted shallowly; If the seedlings are planted too deep, it will be detrimental to the root system. At the same time, the shallower soil layer has lower salt content, which is also conducive to the later growth and development. Fertilizer application: The total amount of phosphorus fertilizer applied is 60kg / hm 2 , and applied as basal fertilizer once, the total amount of pure nitrogen applied during the entire growth period is 150kg / hm 2 , nitrogen fertilizer was applied at a ratio of 80% by weight of base fertilizer and 20% by weight of ear fertilizer; potassium fertilizer was applied at 100 kg / hm2 during the entire growth period. 2 , potash fertilizer is applied at a ratio of 50% by weight of base fertilizer and 50% by weight of ear fertilizer; The traditional fertilization method is to apply base fertilizer, tillering fertilizer, ear fertilizer, and granular fertilizer. The present application optimizes the fertilization method and only applies base fertilizer and ear fertilizer, which reduces the number of fertilizations and does not make the soil fertility insufficient under the support of soil conditioners, reduces the labor input, better meets the planting needs of farmers, improves production efficiency, and reduces the waste of nitrogen resources. (6) Water management: After transplanting rice, observe the growth of rice seedlings. If the tips of rice leaves turn yellow seriously, test the salinity of field water and soil. If the salinity is too high, drain the field immediately and replace it with fresh water resources. At this time, the field water level is mainly deep water, which can dilute the salt in the shallow layer of the soil and has a certain inhibitory effect on the salt in the deep layer of the soil. The water level is two-thirds of the rice seedlings. When the rice is found to be green again and the rice is growing well, adjust the water level to one-third of the rice seedlings. The water level at this time is conducive to the tillering of rice. The relatively shallow water layer is also conducive to the respiration of the soil and the jointing growth of rice in the later stage. When the rice enters the waxy stage, drain and dry it until harvest. (7) Field management: The management of saline farmland is to prevent the saline soil from returning to the rice field and to pay attention to the prevention and control of pests and diseases throughout the growth period. The base fertilizer in step (5) is deeply applied 3-5 days after transplanting the rice seedlings, the ear fertilizer is applied 15-20 days after the rice blooms, the phosphate fertilizer is phosphorus pentoxide, the nitrogen fertilizer is resin-coated slow-release urea with a nitrogen content of 44% by mass as the base fertilizer, the nitrogen fertilizer is urea with a nitrogen content of 46% by mass as the ear fertilizer, and the potash fertilizer is potassium chloride.

[0005] Furthermore, the rice variety in step (3) is Shuangliangyou 138; This variety has a strong ability to withstand high temperatures. On the one hand, it can cope with the high temperatures in the region. On the other hand, its own salt tolerance makes it more conducive to its cultivation in saline farmland areas.

[0006] Furthermore, in step (7), if the tip of the rice leaf first turns yellow-brown, and the veins on both sides of the leaf gradually turn white, this is the initial stage of salt damage. If the base of the rice leaf also turns yellow, the leaf curls and turns yellow, and the root system of the rice gradually turns black and the number of white roots decreases, it means that the salt damage of the rice has become more serious and it is necessary to drain and change the water in time. The time for drainage should be in the afternoon or evening to avoid the upward movement of salt caused by soil evaporation caused by midday solar radiation. Irrigation should be done in the morning or early morning, and it is also necessary to avoid noon because the water temperature in the irrigation equipment is high after being exposed to the sun. Too high water temperature will cause certain damage to the rice.

[0007] Furthermore, in step (7), the pest control adopts a prevention-oriented and prevention-controlled approach. Before the rice becomes diseased, tricyclazole, chlorfenapyr, rice blast-killing agent and other pest control drugs are sprayed in time. If pests are found, the drugs are sprayed immediately. The three drugs are mixed and applied. No more than three types of drugs should be used, as this will reduce the efficacy of the drugs. When applying drugs, the deep water layer should be dominant in the field to prevent the spread of pests.

[0008] Compared with the prior art, the present invention has the following beneficial effects: Effectively utilize industrial solid waste to improve soil, recycle and reuse the clinoptilolite waste and scraps generated in industrial production, and process them into granular clinoptilolite with a particle size of 0.2-0.4 cm, which has the advantages of high quality and low price in improving salt and nitrogen fixation, and can protect the ecological balance and improve the soil environment; Choose nitrogen fertilizers with longer fertilizer effects and optimize the fertilization method at the same time, only apply base fertilizer and ear fertilizer, which reduces the number of fertilization times and does not make the soil fertility insufficient with the help of soil conditioners. It reduces labor input in Hainan's high temperature environment, better meets the planting needs of farmers, improves production efficiency, and reduces the waste of nitrogen resources. DETAILED DESCRIPTION

[0009] The following will be combined with the embodiments of the present invention to clearly and completely describe 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 creative work are within the scope of protection of the present invention. Example 1

[0010] Experimental design: The experiment was conducted from July to October 2023 in Leyi Village, Liguo Town, Ledong Li Autonomous County, Hainan Province. The latitude and longitude of the location are 108.90′E, 18.44′N. The variety selected is Shuangliangyou 138. The experimental design is a split-plot design, with soil conditioners as the main plot and nitrogen fertilizer as the secondary plot. There are 16 treatments in total, 3 repetitions and a total of 48 plots. Nitrogen fertilizer was used as base fertilizer and ear fertilizer for this study. Four soil conditioners (clinoptilolite, humic acid, coconut bran, no conditioner) were used in combination with nitrogen types (urea, ammonium bicarbonate, resin-coated slow-release urea, no nitrogen). The field design is a 20cm earth ridge and drainage ditch around the rice field. Each plot is surrounded by a 20cm earth ridge. The plot is 4m wide and 5m long, with an area of ​​20m 2 , every 16 plots form a row, and a drainage ditch is designed between each repetition for drainage. The farmland is dried in the first two days, and the field is flooded on the third day. The water in the farmland is drained after one day, and irrigation is carried out on the second day. After repeated several times, the salt content in the soil is set to 4‰w / v-5‰w / v; when the white roots of the rice seedlings gradually precipitate and the layers increase, it is the best time for transplanting. At the same time, "shallow seedlings" should be planted during transplanting. On this basis, if the weather is hot, the transplanting time of the seedlings needs to be advanced, otherwise, the transplanting time will be delayed; the types and methods of fertilization are as follows: the amount of pure nitrogen applied during the entire growth period is 150kg / hm 2, deep basal fertilizer was applied 5 days after transplanting rice seedlings, and ear fertilizer was applied 15 days after rice flowering, with 80% basal fertilizer and 20% ear fertilizer. For nitrogen fertilizer, resin-coated slow-release urea with a slow-release period of 90 days and a nitrogen content of 44% was used as basal fertilizer, and urea (N: 46%) was used as ear fertilizer. The total amount of potassium fertilizer (potassium chloride) applied during the entire growth period was 100 kg / hm 2 , according to the base fertilizer: ear fertilizer = 1:1, the total amount of phosphate fertilizer (phosphorus pentoxide) applied is 60kg / hm 2 , and apply it as a base fertilizer at one time. After transplanting rice, observe the growth of rice seedlings. If the tip of the rice leaves turns yellow seriously, test the salinity of field water and soil. If the salinity is too high, drain the field immediately and replace fresh water resources. At this time, the water level in the field should be mainly deep water, and the water level is about two-thirds of the rice seedlings. When the rice shows signs of turning green and the rice grows well, the water level needs to be adjusted to one-third of the rice seedlings. When the rice enters the waxy stage, drain and dry until harvest. During the entire growth period, strictly prevent the saline soil from returning to the salt and the damage to rice and the prevention and control of diseases and pests. If the tip of the leaf first turns yellow-brown, and the veins on both sides of the leaf gradually turn white, it is the initial salt damage. If the base of the leaves is also found to be yellow, the leaves are curled and yellow, and the roots of the rice gradually turn black and the white roots become less, then the salt damage of the rice has become more serious, and timely drainage and water replacement are required. At this time, drainage should be done in the afternoon or evening, and irrigation should be done in the morning or early morning. In the coastal saline farmland area surrounding Ledong Li Autonomous County, Sanya, due to the development of surrounding animal husbandry, weeds are serious around the farmland, and insects such as divaricate beetles, trivaricate beetles and planthoppers will lay eggs here, which will blow to the farmland under the action of wind, causing serious losses to the yield. Therefore, the first step is to spray pesticides to prevent pests and diseases in time, such as tricyclazole, chlorfenapyr, and rice blast. In the second step, if pests and diseases are found, they should be sprayed immediately. Three kinds of drugs should be mixed and applied, and no more than three kinds should be used, which will reduce the efficacy of the drugs. In the third step, when the drugs are used, the deep water layer should be dominant in the field to prevent the spread of pests. Since this is the first time that rice is planted in this farmland, it has been flooded with seawater many times before, so the soil salt content is relatively high. In the early stage of planting, the farmland was drained and washed many times to meet the expected salinity requirements.

[0011] Table 1 Effects of different soil conditioners and nitrogen application types on rice yield and yield components

[0012] Note: S1 represents clinoptilolite, S2 represents coconut bran, S3 represents humic acid, S0 represents no improver; N1 represents urea, N2 represents ammonium bicarbonate, N3 represents resin-coated slow-release urea, N0 represents no nitrogen fertilizer. The treatments were compared with each other. Lowercase letters represent significant differences among the treatments at the 0.05 level, the same below.

[0013] 2. Experimental results The above table shows the yield composition data results in the Ledong coastal saline farmland area in 2023. According to the experimental results, due to the high soil salinity in this experiment, the lemma of rice in the middle and late stages degenerated severely, resulting in large yield losses in the later stages of rice. However, even in the case of high soil salinity, the yield of the treatment with field improvement measures was significantly higher than that of the treatment without field improvement measures, especially in terms of effective panicles and yield. This experiment proves that the measure is active and effective in reducing soil salinity and improving rice salt tolerance.

[0014] Example 2 1. Experimental design: This experiment was conducted from March to June 2024. The implementation site was Leyi Village, Liguo Town, Ledong Li Autonomous County, Hainan Province. The latitude and longitude of the location are 108.90′E, 18.44′N. The variety selected was Shuangliangyou 138. This experiment was designed as a split-plot design. The soil conditioner was the main plot and the nitrogen fertilizer was the secondary plot. There were 16 treatments in total, 3 repetitions and a total of 48 plots. Nitrogen fertilizer was used as base fertilizer and ear fertilizer for this study. Four soil conditioners (clinoptilolite, humic acid, coconut bran, no conditioner) were combined with nitrogen types (urea, ammonium bicarbonate, resin-coated slow-release urea, no nitrogen). This experiment is the second experiment of two years at the same ecological point, so the fertilization method of this experiment is the same as above. As follows: The amount of pure nitrogen applied during the entire growth period is 150kg / hm 2 , deep basal fertilizer was applied 5 days after transplanting rice seedlings, and ear fertilizer was applied 15 days after rice flowering, with 80% basal fertilizer and 20% ear fertilizer. For nitrogen fertilizer, resin-coated slow-release urea with a slow-release period of 90 days and a nitrogen content of 44% was used as basal fertilizer, and urea (N: 46%) was used as ear fertilizer. The total amount of potassium fertilizer (potassium chloride) applied during the entire growth period was 100 kg / hm 2 , base fertilizer: ear fertilizer 1:1, the total amount of phosphate fertilizer (phosphorus pentoxide) applied is 60kg / hm 2 , and applied as basal fertilizer at one time. The salinity required for this experiment was set to 2‰w / v-3‰w / v. During the experiment, the farmland was still washed and drained, transplanted, water managed and managed in the field to achieve the requirements for smooth rice cultivation.

[0015] Table 2 Effects of different soil conditioners and nitrogen application types on rice yield and yield components

[0016] 2. Experimental results The above table shows the yield composition data results in the Ledong coastal saline farmland area in 2024. According to the experimental results, the number of spikelets per ear, the number of effective ears per unit area and the actual yield between different treatments are significantly different. According to the above table, the number of spikelets per ear, the number of effective ears per unit area and the final yield of the treatment with clinoptilolite and resin-coated slow-release urea are all the highest. As a treatment without soil conditioners and nitrogen fertilizers, the values ​​of the above three items are the lowest. Although the other treatments are different from the control treatment, they are not as significant as the effect of clinoptilolite and resin-coated slow-release urea.

[0017] To sum up, the results of the two-year field experiment prove that this cultivation measure has a positive effect on increasing rice yields in coastal saline areas. The soil salinity index and soil fertility conditions in coastal saline areas are key factors restricting local agricultural planting. How to reduce soil salinity and improve soil fertility levels is an important step in solving the salinization problem. In this experiment, first, industrial and agricultural solid waste was effectively used to improve the soil, which not only maintained ecological balance but also improved the soil environment. Second, nitrogen fertilizers with longer fertilizer effects were selected and fertilization methods were optimized, which further improved work efficiency and met the planting needs of farmers. Combined with field cultivation measures that are suitable for planting in saline land, the annual yield was increased and production benefits were obtained.

[0018] The above description is only a preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above embodiment. Any equivalent modifications or changes made by ordinary technicians in this field based on the contents disclosed by the present invention should be included in the protection scope recorded in the claims.

Claims

1. A cultivation method for significantly improving the salt tolerance of rice in saline land, characterized in that: The following steps are involved: (1) Area selection: Select a site adjacent to the sea, with a large area of ​​saline land formed by seawater backflow, which can provide farmland with different degrees of salinization, and has rich meteorological conditions and light and heat resources to meet the basic experimental conditions; (2) Salt washing and drainage and application of soil conditioner: First, build a 20 cm earth ridge around the farmland, dry the farmland in the first two days, irrigate the farmland on the third day, drain the water in the farmland after one day, and irrigate the farmland on the second day. Repeat this process several times to make the salinity in the soil no higher than 5‰ w / v, and the basic soil salinity is controlled at 3‰ w / v; sprinkle 0.2-0.4 cm granular clinoptilolite as a soil conditioner during rotary tillage; (3) Variety selection: Based on the high temperature weather and high soil salinity in the planting area, select rice varieties that are resistant to high temperatures and salt; (4) Transplanting time and method: When the white roots of rice seedlings gradually emerge and the layers increase, it is the best time to transplant. On this basis, if the weather is hot, the transplanting time of the seedlings should be advanced. Otherwise, the transplanting time should be delayed. When transplanting, the seedlings should be transplanted shallowly; (5) Fertilizer application: The total amount of phosphorus fertilizer applied is 60 kg / hm 2 , and applied as basal fertilizer once, the total amount of pure nitrogen applied during the entire growth period is 150kg / hm 2 , nitrogen fertilizer was applied at a ratio of 80% by weight of base fertilizer and 20% by weight of ear fertilizer; potassium fertilizer was applied at 100 kg / hm2 during the entire growth period. 2 , potash fertilizer is applied at a ratio of 50% by weight of base fertilizer and 50% by weight of ear fertilizer; (6) Water management: After transplanting rice, observe the growth of rice seedlings. If the tips of rice leaves turn yellow severely, test the salinity of field water and soil. If the salinity is too high, drain the field immediately and replace it with fresh water resources. At this time, the field water level is mainly deep water, and the water level is two-thirds of the rice seedlings. When the rice shows signs of turning green and the rice is growing well, adjust the water level to one-third of the rice seedlings. When the rice enters the waxy stage, drain and dry it until harvest. (7) Field management: The management of saline farmland is to prevent the saline soil from returning to the rice field and to pay attention to the prevention and control of pests and diseases throughout the growth period. The base fertilizer in step (5) is deeply applied 3-5 days after transplanting the rice seedlings, the ear fertilizer is applied 15-20 days after the rice blooms, the phosphate fertilizer is phosphorus pentoxide, the nitrogen fertilizer is resin-coated slow-release urea with a nitrogen content of 44% by mass as the base fertilizer, the nitrogen fertilizer is urea with a nitrogen content of 46% by mass as the ear fertilizer, and the potash fertilizer is potassium chloride.

2. A cultivation method for significantly improving the salt tolerance of rice in saline land according to claim 1, characterized in that: The rice variety selected in step (3) is Shuangliangyou 138.

3. The method for significantly improving the salt tolerance of rice in saline land according to claim 1, characterized in that: In step (7), if the tip of the rice leaf first turns yellow-brown, and the veins on both sides of the leaf gradually turn white, this is the initial stage of salt damage. If the base of the rice leaf also turns yellow, the leaf curls and turns yellow, and the root system of the rice gradually turns black and the number of white roots decreases, it means that the salt damage of the rice has become more serious and it is necessary to drain and change the water in time. The time for drainage should be in the afternoon or evening, and the time for irrigation should be in the morning or early morning.

4. The method for significantly improving the salt tolerance of rice in saline land according to claim 1, characterized in that: In step (7), the pest control adopts a prevention-oriented and prevention-controlled approach. Before the rice becomes diseased, tricyclazole, chlorfenapyr, rice blast-resistant and other pest control drugs are sprayed in time. If pests are found, spray the drugs immediately. The three drugs should be mixed and applied. No more than three types should be used, as this will reduce the efficacy of the drugs. When applying drugs, the deep water layer should be dominant in the field to prevent the spread of pests.

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