How to use smoke agents for greenhouse flowers with good results
Smoke agents, abbreviated as smoke formulations, are prepared from pesticide technical material, heat-generating agents, combustion-supporting agents, dispersants and others using special methods. When ignited, they can burn (without flame), causing the pesticide to vaporize under heat and condense into solid particles in the air. This type of pesticide is mainly used for the prevention and control of diseases and insect pests in greenhouses and plastic sheds, and is a new type of application method.
In recent years, with the development of facility agriculture, the area of flower greenhouse cultivation has increased year by year. Due to the unique microclimate of greenhouses and the cyclical influence of vegetable cultivation, some diseases and insect pests occur relatively seriously. In the prevention and control of diseases and insect pests, a relatively effective means is to use smoke agents for fumigation control. It has high efficacy, low residue, saves time, labor and pesticide, requires no equipment, is convenient to use, and generally does not cause diseases to develop resistance, avoiding the waste phenomenon of conventional spray pesticides. Therefore, many greenhouse growers often use smoke agents to prevent and control diseases and insect pests. However, certain methods need to be mastered when using smoke agents.
1. It is necessary to match the treatment to the disease
The performance of various smoke agents is different, and their control targets are also different. Therefore, when using smoke agents, only by correctly selecting the variety of smoke agent according to the type and degree of occurrence of diseases and insect pests, and matching the treatment to the disease, can the effect of high control efficacy, saving money and saving labor be achieved. For example, when controlling leaf mold in sheds and greenhouses, Procymidone smoke agent can be selected; when controlling downy mildew and blight, chlorothalonil smoke agent can be selected for control.
2. It is necessary to master the appropriate timing of application
Generally speaking, applying the pesticide at the early stage of disease and insect pest occurrence gives good results. This is because at this time the occurrence quantity is small, making it easy to control, and at the same time the pests are at the young stage and have poor natural resistance to the pesticide. For example, when using Cucurbit Aphid Smoke Agent No. 1 to control aphids, when the aphid occurrence quantity is small, applying 250-300 grams per mu is sufficient.
3. It is necessary to master the appropriate amount of application
Generally, the dosage used should be determined according to the size of the greenhouse space, the degree of occurrence of diseases and insect pests, and the effective content of the smoke agent. Under normal circumstances, the single dosage of 30% chlorothalonil smoke agent and 10% Procymidone smoke agent is 0.3 to 0.4 grams per cubic meter, equivalent to 300-400 grams of smoke agent per mu. If the disease and insect pests are severe or the greenhouse is poorly sealed, the dosage can be appropriately increased.
4. It is necessary to master the application time well
Generally, it is suitable to ignite after covering the straw curtain in the evening, and igniting the smoke agent on the evening of a cloudy or snowy day gives even better results. This is because under sunlight, the surface temperature of the plants is the same as the temperature of the smoke agent particles, and the smoke is not easy to deposit, thus affecting the efficacy, while in the evening or on cloudy days, it is favorable for the deposition of the smoke.
5. It is necessary to master the method of use well
When using, do not place the tablets directly on the ground. The scientific method is to place the smoke agent tablets on bricks, or hang them on iron wires inside the shed, and keep equal distances between the tablets. For sheds and greenhouses with relatively large spaces, when using smoke agents with lower effective ingredient content (10%-30%), generally set 3-5 ignition points per mu; when using smoke agents with high effective content, it can be increased to more than 5 points per mu; for sheds and greenhouses with small, low spaces, it is advisable to choose smoke agents with low effective ingredient content and set 7-10 ignition points per mu. After the tablets are placed, seal the greenhouse and ignite each tablet in sequence from inside to outside. Be careful to blow out the open flame, which is favorable for producing thick smoke for fumigation. After continuous fumigation for 5 to 6 hours, open the shed for ventilation. Fumigate once every 7 to 10 days, and continuous fumigation 2 to 3 times can achieve good results.
6. It is necessary to pay attention to effective application
When using smoke agents, be sure to check the shed or greenhouse and make sure it must be sealed. At the same time, also pay attention. Smoke agents are prone to moisture, so they should be protected from moisture during storage. Once damp, they can be placed in a ventilated place to slowly air-dry, and must never be roasted with fire. When using the pesticide, pay attention to avoiding crops and flammable items. After ignition, the operator should immediately leave the shed and close the shed door. Only after ventilation for 2 hours the next day may one enter the shed to prevent poisoning. After contact with this pesticide, wash with soapy water.