Other fungicides

A bactericide is a chemical that kills or inhibits fungi or bacteria. The bactericide can kill or inhibit the growth and reproduction of the pathogen by the virulence of the agent in vitro or in the plant. Some fungicides are not toxic to fungi, but can interfere with fungal pathogenesis or affect the pathogen-host relationship and improve plant defense capabilities. Non-toxic fungicides: The activity of fungi affects the pathogenicity of fungi; affects the relationship between host and pathogens, and improves the disease resistance of plants. The effect of tricyclazole on Magnaporthe oryzae is to inhibit melanin synthesis invading the cell wall during spore germination, and the result is that it cannot penetrate the host cell and cause invasion. That is because it affects the tightness of the invading plug cell wall and the intracellular necessary swell pressure. When dichlorodimethylcyclopropanecarboxylic acid (DDCC) is sprayed on rice leaves, it can prevent the enlargement of rice blast lesions because the agent promotes the accumulation of plant defensin momilictones A and B in the tissues surrounding the lesions, so that the invasive sites The hyphae must not spread and spread. Toxic base and auxiliary base: The fungicide has a killing or inhibiting effect on the pathogen and is related to the molecular structure of the fungicide. Each bactericide must have a virulence gene or a toxic element in its molecular structure. For example, mercury in organic mercury compounds, trichloromethylthio group of captan. The virulence of the fungicide to the fungus is that these groups and elements destroy the metabolism of the bacteria and eventually cause the bacteria to die. There is also a certain auxiliary group in the structure of the fungicide, which can adjust the physicochemical properties of the compound. For example, the butylamine formyl group in the benomyl structure has strong lipophilic properties, which increases the ability of the agent to penetrate into the bacteria, thereby enhancing the antibacterial action of the agent. According to the action of sterilization, it can be divided into a reducing fungicide and an oxidizing fungicide. According to the principle of prevention of plant diseases by fungicides, it is divided into protective agents, therapeutic agents, and eradicators. According to the main components of the fungicide, it can be divided into inorganic fungicides, such as sulfite, bleaching powder, copper sulfate, etc.; organic fungicides, such as perpropionic acid, "cyantan", benzoic acid, sorbic acid, "desen zinc" Etc.; organic ketone fungicides such as trichlorophenols; organic mercury fungicides such as sulfamethoxazole, chloroethylmercury, etc.; organochlorine fungicides such as pentachlorophenol, "bactericidal", dichloronaphthylquinone, etc.; Agents such as aminobenzenesulfonic acid; thiocyanate fungicides such as dinitrogen; phenolic fungicides such as phenol, salicylanilide; aldehyde fungicides such as formaldehyde; ester fungicides such as parabens Etc.; surfactant bactericide and the like. According to the route of use of the fungicide, it is divided into a seed treatment agent, a soil treatment agent, and a foliar spray agent. According to the absorption and running performance of the bactericide in the plant, it is divided into a non-systemic bactericide and a systemic bactericide. According to the use, it is divided into general purpose, edible, medical, agricultural and animal husbandry, cleaning, leather, paint and other special fungicides.