The Manufacture And Control Effect To Pseudoperonospora Cubensis Of Photocatalytic Nanometer Titanium Dioxide

Titanium dioxide, as a kind of photocatalytic semiconductor, is not only nontoxic and low-cost, but also noncorrosive. Under the sunlight, redox is caused by nanometer TiO₂ and active oxygen is produced such as O₂ or hydrate. They can decompose organism around and kill microbes such as bacteria, viruses etc. It is a kind of perfect antimicrobial. Resultingly, TiO₂ can be used to clean air and water pollution. It is promising in agricultural field.At present, it is rarely reported that plant diseases are controlled by nanometer TiO₂. In experiment laboratory, the method was improved to get nanometer TiO₂ and the activities were tested by different methods. On the base of pathogens disinfection experiments indoor, nanometer TiO₂ was used to control plant diseases-cucumber downy mildew (Pseudoperonospora cubensis) outdoor.1) Nanometer titanium dioxide was got by liquid method. Compared with traditional method, the craft of the method is simple and the reaction condition is easy to get. It is a revolutionary method with superiority.2) The influences of several factors were tested on TiO₂ manufacture. Water quality, pH, reacting time and temperature had great influence on the results. The factors should be considered in the experiment.3)The activities of TiO₂ were tested with filter-paper method, porcelain method, gauze method and so on. The same conclusion was drawn by different methods that TiO₂ had high activity. In the experiment, illuminant is the restrictive factor. Photocatalysis can't work without it.4) It was found that TiO₂ had disinfection to plant pathogens. In the field experiment, disease index of treatments were evidently lower than that of CK, the control effects to cucumber downy mildew were 45.37%⁵6.87% and cucumber leaves of treatments grew stronger than CK and other treatments.The research will provide technology basis for the application of photocatalytic materials in plant protection.