Soil problem, a major subject of modern agriculture!
In the first 10 years, our agriculture has been in the stage of continuous pursuit of yield. The frequent use of pesticides, fertilizers and regulators and the very common use of supersaturation have made our soil continuously deteriorate. Salt accumulation, pH value rise, hardening, epidemic diseases, pests and weeds are becoming more and more difficult to control, and even sitting obstacles have become difficult problems for us to solve.
On the one hand, the soil problem is becoming more and more serious, on the other hand, the market demands higher and higher quality of agricultural products, and growers need real benefits. Only by breaking through these three problems can we embark on the road of healthy and rapid development.
According to the advanced experience at home and abroad, the core way to solve the soil problem is to apply fertilizer rationally and use drugs scientifically; Secondly, in combination with soil improvement, crop rotation, fallow, soil disinfection, soilless cultivation, facility agriculture and other methods, we should select their strengths and combine them with ourselves to scientifically and rationally develop, utilize, fill and improve the soil, so as to achieve the goal of high yield and sustainable utilization of soil.
Next, we will focus on rational fertilization; Scientific medication; Soil disinfection.
1、 Rational fertilization and scientific drug use
Fertilization principle: timely, appropriate, proper method and suitable planting, which is interpreted as selecting the appropriate amount and formula of fertilizer for different time and growth stages, and applying the most appropriate method to the target crops. In order not to damage the soil, the passage, fixation, pH, adsorption, anion and cation supply ratio and antagonism of fertilizer must be considered. Plants need 16 kinds of nutrients, and the applied fertilizers are mainly simple fertilizers Compound fertilizer (water-soluble fertilizer&slow-release fertilizer) is a complex systematic project, which is well prepared and used for target crops.
Plant protection policy: prevention first, comprehensive prevention and control. The use of pesticides must focus on agricultural prevention and control, supplemented by chemical prevention and control. Chemical prevention and control should be tailored to the situation, safe and reasonable. Scientifically mix and rotate, design the drug use plan for the whole growth cycle, strictly control the pesticide dosage, safety interval and residual degradation time, and consider the economic threshold and natural enemy avoidance.
2、 Soil disinfection
At this stage, soil disinfection is one of the best ways to eliminate sitting disorder, solve excessive use of pesticides, and improve yield and quality. Soil disinfection mainly includes chemical disinfection and physical disinfection. The cost of physical disinfection is high, and there are many affected conditions. Let's explain chemical disinfection in detail:
Selection and dosage of fumigant
It is recommended to select chemical disinfectant: Mianlong, which is low toxic and efficient, safe and convenient to use, and is more suitable for our current agricultural planting situation.
According to the test, the dosage of 98% Mianlong granules is 20-40 kg per mu. At present, it has very good effects on ginger, strawberry, flowers and panax notoginseng in China.
1. Land preparation
The land shall be leveled, debris shall be removed, and the soil shall be fully broken. The residual roots of plants, crop straws, large soil blocks, stones, etc. in the field soil shall be removed.
Watering before spraying to break the dormancy of pathogenic bacteria and weeds. First, level the land. 5-7 days before spraying, water the soil to be disinfected thoroughly, or 5-7 days after rain, when the soil humidity is about 65%.
3. Evenly sprinkle medicine
Weigh the linter first, and then evenly spread it on the soil surface. In order to spray evenly, a powder spraying machine can be used to spray evenly.
After spraying the agent, use a rotary cultivator to evenly mix Mianlong granules in the soil. If root knot nematodes are controlled, the mixing depth should reach 30cm.
5. Cover with plastic film
After watering, immediately cover with plastic film and compact around. The days of film covering are affected by the temperature. The lower the temperature, the longer the film covering time.
6. Uncover the film
Peel off the film 7-15 days before planting or transplanting. After the membrane is removed, the soil shall be turned over for ventilation. The lower the soil temperature is, the longer the air diffusion time will be. Cotton should be used at least 4 weeks before sowing or planting. The temperature at 250mm depth of Mianlong soil should be above 12 ℃.
What are the precautions for the mixed soil application method?
(1) When applying medicine, wear rubber gloves, masks, boots and other safety protective equipment to avoid direct skin contact with the medicine. Once the skin is contaminated, wash it thoroughly with soap and water immediately;
(2) When spraying medicine, you should carry your back against the wind.
(3) The medicine is toxic to fish and prevents the powder from drifting to the nearby pond;
(4) The storage shall be sealed in the original package and stored in a cool, dry place;
(5) It shall not be stored together with food and feed.
It is very important to avoid reintroduction of pests and diseases after soil disinfection. Soil diseases and insect pests, including fungi, bacteria, nematodes, weeds and insects, occur and develop faster in the disinfected environment. In order to prevent soil borne diseases from being introduced into the treated soil, how should field management be carried out after soil disinfection?
1. First, select disease free varieties
Select good disease resistant varieties, and select disease resistant varieties suitable for local cultivation according to the development of local vegetable diseases and insect pests, so as to achieve the method of matching good varieties.
2. Seed disinfection
Seed disinfection before sowing, such as soaking seeds in warm soup, high temperature dry heat disinfection, seed dressing with medicament, and seed soaking with medicament, can reduce or resist the occurrence of diseases.
3. Seedling bed disinfection or substrate cultivation
It is better to use substrate culture. If there is no suitable substrate, the raw soil on the hillside or the field soil without vegetables can be used. The farmyard manure used for preparing nutrient soil shall have been decomposed and not polluted by vegetable residues. If the seedbed soil cannot be guaranteed to be free of germs, fumigants can be used for disinfection, and weeds and underground pests in the seedbed can also be controlled.
4. Do a good job of prevention
In order to reduce the risk of insect pests spreading to the soil that has been exterminated and avoid bringing untreated soil from the surrounding farms, the following measures can be taken:
(1) Before using machines and tools in the soil after pest control, clean the untreated soil adhered to the machines and tools;
(2) Avoid your shoes and clothes bringing untreated soil into the treated fields, especially when planting;
(3) When removing the tarpaulin after soil treatment, be careful not to spread the untreated soil
(4) Do not cultivate under the treated soil layer (which may bring up pests);
(5) It is better to have a clean water pool at the entrance of the greenhouse, and put disinfectant into it to disinfect when entering the greenhouse.
In order to prevent soil borne diseases from entering the treated soil, field management after soil disinfection is very important, and it is also critical to master the planting time after fumigation.
The planting time after fumigation depends on the exposure time after treatment, so that the fumigation toxic gas can be emitted to avoid pesticide damage when planting crops. The planting time after fumigation is largely related to the characteristics of fumigant and soil conditions, such as soil temperature and humidity. When it is cold and wet, the open time shall be increased; When it is hot and dry, it can reduce the exposure time; The open time of high organic matter soil should be increased; Clay requires longer exposure time than sand.
We can qualitatively judge whether there is pesticide residue by germination test, that is, take two jars, one of which is quickly filled with half a bottle of fumigated soil, and the other is filled with half a bottle of unfumigated soil. (Note that the soil at the lowest position in the same field can be taken for sampling, and the residual soil here is relatively high.) Then use tweezers to spread a piece of wet cotton on the top of the soil in a can, and then put 20 lettuce seeds on the cotton, and cover the bottle. Put the jars in the room without direct light for 2-3 days. After 2-3 days, take out cotton blocks, count the number of lettuce sprouts, and observe the state of seedlings. If lettuce sprouts less or the root tip burns, it indicates that there is fumigant residue. If the unfumigated soil germinates less than 15 pieces, or the root tip of lettuce is burned, replace the lettuce seed and retest. If the number of germinated soil after fumigation is less than 15, repeat the test after one week. If the number of lettuce sprouts in the fumigated soil is more than 15, and there is no root tip burning, it can be planted.