GENETIC INVESTIGATION OF FUSARIUM RESISTANCE IN CORN

Fusarium related mycotoxins represent an issue in maize cultivation in many world areas, including Italy. The proven toxicity of this class of metabolites induced the major health organization to emanate rules for limiting their presence in human food and animal feed. There are several known physiological mechanisms involved in resistance but little knowledge is available about the genetic bases of this resistance. Aim of the work was the investigation of the genetic base of the resistance to Fusarium. The visual selection against the presence of the pathogen is an effective method to reduce the occurrence of the mycotoxins. Based on this observation it is possible to avoid in the first steps of selection the highly costs analyses of fumonisin content. Analysis of a segregant population, tested for two consecutive years in Northern Italy experimental fields, revealed the presence of a genomic region on chromosome one associated with the trait. The relevance of this marker was confirmed across seasons, in natural and artificial inoculation trials. Investigation of this region, the one with the most effect on the trait, leads the proposal of a candidate gene approach for the resistance effect although further investigation are needed to confirm this preliminary hypothesis. Detected marker could be useful in marker assisted selection breeding programs in order to favorite the development of resistant germplasm.