Resistance of mechanisms of maize populations native to M?xico against the weevil Sitophilus zeamais

Sitophilus zeamais (Motschulsky) (Coleoptera: Curculionidae) is a pest responsible for enormous postharvest grain losses of maize, estimated at 60 % during the first six months of storage. This study evaluated the resistance of five native maize populations in Mexico to damage caused by S. zeamais. It was appreciated that the populations of the color 'VAN-Blue' and 'VAN-Variegado' were hard, while the white hybrid 'AN-456' and 'VAN-Red' were moderately hard. In free choice (antixenosis), 'VAN-Blue' and 'VAN-Purple' exerted repellency on adults of S. zeamais. The 'VAN-Blue' population lost less weight to the attack of S. zeamais; however, 'VAN-Red' and the white hybrid 'AN-456' were highly susceptible. The antibiosis effect was manifested after 45 days post-infestation (dpi) in the white hybrid and 'VAN Blue' with the lowest damage rate (38 %). Adult mortality ranged from 100 % in 'VAN-Purple' at 60 dpi. A positive correlation existed between antixenosis parameters and weight loss. The 'VAN-Purple' and 'VAN-Blue' populations showed the best resistance characteristics against S. zeamais damage, suggesting that they are potentially useful as a breeding option for developing improved varieties with resistance characteristics against S. zeamais attack.