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Maize is an important cereal crop in the world. 1998 corn production has more than rice and wheat, the highest in the world. Corn known as one of the most important crops in the world can be processed to form the total amount of diversified products and potential is not a substitute for any kind of crop. Especially for continuous research and development of animal husbandry, industry, soft drinks, adhesives, fuels and other products, corn presents an increasingly important value in the national economy. In view of the important position of corn, the corn has been the people's attention. Corn infected with aflatoxin in maize grain around the world corn production areas generally occur in the pre-and post-harvest and during storage highly susceptible to Aspergillus flavus infection, it not only makes the decline in maize quality, and its metabolite aflatoxin is strongly induced The carcinogen seriously endanger the security of people and livestock. To carry out anti-aflatoxin genetic breeding, proven genetics and mechanisms of resistance to aflatoxin in corn, nurturing Resistance to Aspergillus species is to solve the fundamental method of aflatoxin corn contamination. Corn aflatoxin bacteria resistant major QTL positioning, laid the foundation for molecular marker-assisted selection and molecular level resistance breeding, so as to reduce aflatoxin contamination in the production, to provide protection for people's health. This experiment, artificially inoculated with Aspergillus flavus parental RA (disease) and M5P (susceptible) and separated progenies F2: 3 families, adopting a classification determined resistance, will be divided into 10, combined with multi-state sexual SSR markers for QTL mapping resistance genes specific findings are as follows: 1. groups 181 F2: 3 Seed Resistance Identification of Aspergillus flavus, results showed: the entire F2: 3 population, resistance than Strong (1-3) the number of home-based 32, the four pedigrees does not exist any resistance (8-10); the 48 pedigrees Resistance weak (5-8); 93 the resistance level of the pedigree Medium (3-5), the level of resistance of the entire group close to a normal distribution. The parental inbred lines with high resistance to Aspergillus flavus inbreds RA and high sense of Aspergillus flavus M5P screened from 786 pairs of SSR molecular marker amplification effect between parental performance polymorphic SSR markers 80 Dui, genotyping by the resistant parent of the RA and the sense of disease pro-the M5P separating out the F2: three lines of plants, build a cover corn seven chromosomes of the genetic map, the total genetic distance as 447.27 cM, molecular markers average distance 10.91 cM. 3 the use of MapQTL5.0 software and interval mapping method detected three QTLs for resistance to aflatoxin, which are located on chromosome 5, 6 QTL on chromosome 5 In between to mark umc1155 and phi048, LOD value of 2.0 can explain the phenotypic variation was 8.7%. Two QTL on chromosome 6 are located mark umc1887, umc2317 and mnc0523 between 2.66 and 3.02, LOD value interpretable table variation were 9.6% and 19.3%, LOD score of 3.02 QTL, as The main effect the QTL.
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