Abstract

Environmental variations caused by climate change have been increasing the impact and risks on maize (Zea mays L.) production, due to biotic factors like crop pests and diseases attack, which presence are altered by changes in abiotic climate conditions such as temperature and precipitation between others; the fungus Aspergillus flavus that in maize kernel develops aflatoxins (AF), a potent carcinogenic substance produced by this fungus which affects considerably animal and human health. For that reason, the development of AF resistance maize genotypes with good yield performance and agronomical quality become very important. Recent research conducted by National Institute of Forestry, Agricultural and Livestock Research (INIFAP) and the National Autonomous University of Mexico (UNAM) identified AF genetic resistant materials, nevertheless these materials had limited yield performance. INIFAP Maize Breeding Program initiated the development of superior inbred lines by pedigree selection, which might allow to obtain experimental hybrids with AF resistance and good grain yield potential. The objective of this study was to identify outstanding hybrids with AF contamination resistance. A new group of experimental hybrids formed by selected inbred lines were evaluated for grain yield during summer 2015 at Celaya, Gto. and Morelia, Mich., Mexico; under a 9 X 9 lattice design with two replications, another field experiment was conducted at Rio Bravo, Tam., Mexico were the presence of aflatoxins is endemic. At laboratory were analyzed two types of samples, the first from the inoculation with A. flavus of a set of seed of the hybrids used for field evaluation; and second from samples obtained from Rio Bravo field experiment. Results from field and laboratory allow identifying 19 statistically superior hybrids in yield and agronomic performance with a range of 8.6 to 11.6Mg ha^-1 with good resistance to AF from the field, with values below 20ppb.

Keywords: Zea Mays L.; Aflatoxins resistance; Pedigree selection; Hybridization