Introduction Fusarium semitectum is

Introduction Fusarium semitectum is one of the most fungi in corn that found in Thailand. The infection of cereal grains with Fusarium semitectum can cause contamination with mycotoxins that affect human and animal health. The conventional method to control are usually treated with fungicide and chemical, the products-target contaminated with chemicals and influences of the development of resistance and mutation by the pathogens. So that in crop production requires the method to control the fungus which are more safety for consumer and friendly to environment. The radio frequency application could be one of the solutions to eliminate this problem. The thermal energy of radio frequency is transport as heat by convention and conduction from the inside (Internal heating); the heat is generated with in the material rapidly. It possible to eradicate the fungi inside of the grain, save of time and energy.
Materials and Methods The corn with the initial moisture content 10.5 and 14 % were treated with radio frequency heat treatment on a varies temperature. It was treated at the temperature of 65, 70, 75, 80, 85 C for 600 seconds. The parameters measures continuously during the process were: the product temperature by fiber optic temperature measurement, duration of application, application power and reflected power. The infection of Fusarium semitectum was assayed by Potato Dextrose Agar (PDA) method under the steriomicroscope according to ISTA rule (2004).
Results and Discussion Exposure of corn grain to radio frequency heat treatment result in the reduction of fungus. When naturally infected grain were treated with radio frequency, the percentage of fungus was suppressed as showed by the decreased in the percentage of Fusarium semitectum infection rate (table 1). The high percentage of corn grain was found infected by Fusarium semitectum. The most infection was associate with the level of the initial grain moisture content, the corn with 14 % initial moisture content had the percentage of Fusarium semitectum high to 96 % more than the corn with the initial moisture content 10.5%, and it was 83 %.