High temperature stuffy shed, 8 big essentials!If you don't use it well, it's useless

  At present, most of the solar greenhouses enter the summer high-temperature leisure period, which is a good time for high temperature suffocation. High temperature shack is a technical measure for green prevention and control of pests and diseases. Is this seemingly simple conventional technical measure, are you right? Without mastering the essentials, the effect will be greatly reduced. To this end, Professor Wang Guangyin, a specialist in the vegetable technology system of Henan Province, gave detailed answers to the concerns of growers.

01

High temperature suffocating shed, is it really "dry", or "wet stuffy"?

Dry high temperature shacks refer to the shacks after the crops are pulled, without watering, and directly sealed in the greenhouse. Dry high temperature shacks can only increase the local space temperature above the ground, and have little effect on killing pathogens and pests in the soil layer, so it is less used in actual production.

The wet high temperature shack is a common shed disinfection measure in production. The principle is to water the greenhouse soil, and the heat conductivity of the water is higher than that of the soil, so that the soil tillage layer reaches a higher temperature. At present, the wet high temperature shack measures used in actual production mainly include direct high temperature shacks, high temperature suffocating sheds for organic fertilizers, high temperature shacks for straw returning, and high temperature suffocating sheds for lime nitrogen (calcium cyanamide).

"Dry stuffy" can only kill the pests on the surface of the shed. If "dry" and "wet stuff" are combined, the effect of sterilization and pest control will be more thorough and comprehensive.

02

Simple sunburn shack is good? Or add organic fertilizer, straw fertilizer, lime nitrogen and other shacks?

Tests have shown that high temperature stagnation combined with fertilization effect is better. In particular, the combination of straw fertilizer and lime nitrogen is the best, which can reduce the use of chemical pesticides and reduce the harm of continuous cropping obstacles.

The specific compound treatment method is: clean the shed after the harvest of the upper crop, and evenly spread the straw such as corn and straw every 667 m2 (the finer the smash, the better) 2000~3000kg, the lime nitrogen 40~80kg, the rotary tiller The straw and lime nitrogen are turned into the soil (20~30cm deep), mixed evenly, and leveled and built. The surface of the soil is covered with mulch, and the ditch is filled with water until the shed is wet and there is water. During the shack, if the soil is short of water, it can be refilled once. Closed greenhouses, if the greenhouse has broken, it should be repaired in time. The use of sunlight to rapidly heat up the greenhouse (surface temperature up to 70 ° C) for more than 20 days. After the suffocating shed, the film should be ventilated for 5-7 days, and the fertilizer such as biological fertilizer should be applied, shallow ploughing, soil preparation, and hoeing, ready for planting.

03

Does lime nitrogen need to be applied annually?

The lime-nitrogen high temperature stagnation technology is a comprehensive solution to the problem of soil continuous cropping obstacles. Due to the relatively high cost of lime nitrogen, the use of this technology is not universal, and it is mainly suitable for greenhouses or solar greenhouses with long-term planting diseases, serious continuous cropping obstacles, and root-knot nematode diseases. Considering the cost and control effect of lime nitrogen, it is recommended to use 60kg per 667m2 in production. Disinfection with lime nitrogen is usually carried out once every two years.

04

In addition to lime nitrogen, are there other disinfecting drugs?

It is also possible to use a fungicide such as carbendazim or chlorothalonil wettable powder to control diseases. Each 667m2 can be mixed with 50% carbendazim WP 2~3kg and 20~30kg ammonium bicarbonate, and evenly spread on the ground, deep turning 15~20cm. In addition, before the greenhouse was closed, carbendazim was sprayed once more on the inner surface of the shed and fumigation with 10% isopropanol to kill the germs and pests hiding in the wall. In production, the organic fertilizer can be fermented in advance, evenly applied into the shed, and then sprayed or applied to the surface of the manure and the soil, and the combination of fertilization, application, cultivation, and shacking can be promoted. After the manure is ripe, improve fertility, enhance the efficacy of the drug, and so on.

05

After high temperature suffocation, do you need to apply drugs to control root-knot nematodes?

Using the "sunlight-lime nitrogen" compound shack method to treat the greenhouse soil, the control effect of tomato, cucumber and pepper root knot nematodes can reach 90%. After planting or slowing down the vegetables, each plant (cucumber, tomato) can use 500~1000 times avermectin 200mL to root, which will have better effect on controlling soil-borne diseases.

06

Is the high temperature shack covered by a single film or is it covered with a double film?

The high temperature shack requires the shed to be closed, not only to close the venting vent of the shed, but also to cover the mulch on the shed floor. Many vegetable farmers do not cover the mulch, resulting in lower soil temperature and poor stagnation effect. The lethal temperature of the root-knot nematode is 55 ° C, and it dies in 10 minutes at 55 ° C. If the mulch film is not covered, the temperature of the deep layer of the soil is low, and it is difficult to achieve the effect of thorough sterilization and insecticide. Therefore, it is still good for double film coverage.

07

How much does high temperature shack irrigation affect the effect?

Tests have shown that the soil water content is closely related to the effect of bactericidal and insecticidal, and the effect is too low to achieve the effect of sterilization and insecticide. Generally, 70% of the field water holding capacity is the best. Therefore, before the shed, the water must be flooded, so that the soil forms an oxygen-deficient environment, which is more conducive to killing pests and diseases. At the same time, pouring large water can also bring the soil salt to the deep layer of the soil, which can reduce the salt content of the soil.

08

After high temperature suffocation, must the soil be applied with biological fertilizer?

After high temperature, most of the harmful bacteria or beneficial bacteria will be killed. Therefore, after the end of the high temperature suffocating shed, biological fertilizer or bio-organic fertilizer should be added to increase the beneficial bacteria in the soil, protect the rhizosphere environment, and enhance the disease resistance of the plants. Special need to be reminded that: biological bacterial fertilizer or fungicide, must not be applied before the high temperature shack, must be applied after the high temperature shack, otherwise the beneficial bacteria will be killed by the high temperature when the shed.