Detailed Introduction to Organosulfur Pesticides

① Zineb: It is a 65% zineb wettable powder, commonly known as Daconil-78. It is an extremely effective preventive fungicide with lasting efficacy and belongs to the broad-spectrum fungicides. It has a preventive effect against pathogens such as Colletotrichum spp. and Cercospora spp. When this agent is applied during periods of high temperature and high humidity, if the dilution ratio is improper, phytotoxicity may occasionally occur. When using this agent, it must not be mixed with alkaline pesticides or fertilizers. ② Maneb: It is an 80% maneb wettable powder, commonly known as Daconil-22. It is a broad-spectrum preventive fungicide, and its fungicidal effect is better than that of zineb. It has a preventive effect against pathogens such as Fusarium spp., Cercospora spp., and Colletotrichum spp. When applied during periods of high temperature and high humidity, there is a risk of phytotoxicity. If this agent is accidentally splashed onto the skin during application, it can easily cause skin allergies or dermatitis. Safety protection measures should be taken in advance when applying this agent. ③ Zineb-maneb: It is an 80% zineb-maneb wettable powder, commonly known as Daconil-45. Its fungicidal effect is poor, it has no therapeutic effect, and it is a protective preventive fungicide. It can be mixed with a variety of pesticides and fertilizers. It has a preventive effect against pathogens such as Fusarium spp., Cercospora spp., and Septoria/Phomopsis spp. For Chinese orchids with poor growth vigor, using this agent can easily inhibit their growth. Especially when used during the flowering period, it easily causes phytotoxicity. In the application of organosulfur pesticide formulations, for the more sensitive Chinese orchid plants, their tolerance to pesticides is relatively low. When using organosulfur pesticides as agents for preventing and controlling Chinese orchid diseases, lower dilution ratios are often required to achieve the control effect, and their fungicidal action depends on the agent being applied to the plant, where the organosulfur undergoes a chemical reaction, enters the pathogen or plant body and causes a reaction, thereby producing a fungicidal and fungi-preventing effect. WhenCultivationthe manager applies excessive amounts of chemical pesticides such as zinc, manganese, or zineb-maneb, the Chinese orchid plants absorb and accumulate excessive amounts of this type of agent, causing a certain trace element to accumulate beyond its tolerable critical point, resulting in a disorder in the plant's or root system's ability to absorb nutrients, which easily causes nutritional disorder. In addition, there are many brands of organosulfur pesticide formulations on the market, and the pH value of the organosulfur pesticide formulations produced by each manufacturer differs somewhat. Some brands have a pH value as high as between 8 and 9,CultivationIf the manager, without knowing the situation, mistakenly uses a brand of agent with a higher pH value and mixes it with other pesticides or fertilizers that are not stable under alkaline conditions, the pesticide can easily lose its fungicidal power and the effort will be wasted. Moreover, when this type of pesticide is generally applied, the recommended dilution ratio is relatively low, and a higher amount must be used to achieve the desired effect. After application, pesticide spots often remain on the leaves and cannot be washed off with clean water. The agent easily adheres to the leaves for a long time or clogs the stomata, thereby affecting photosynthesis, transpiration, and the plant's appearance, and further affecting root growth. Over time, both quality and quantity will decline.