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Sitotroga cerealella is the main pest of maize grains and Mythimna unipuncta is a generalist defoliating pest that often attacks maize. Two Tepary bean (Phaseolus acutifolius) genotypes, Tepary pinto yellow (Yellow T) and Tepary pinto negro (Black T), repel pest attacks on beans and, since beans and maize have co-evolved in America, we hypothesized that they could also protect maize against the attack of similar pests. Yellow T showed antixenosis against larvae in young maize plants. Pinto Saltillo (P. Saltillo) (P. vulgaris) and Yellow T controlled the consumption of maize leaves. No significant differences were found between these two genotypes for Mythimna unipuncta growth in bioassays with artificial diets. We found significant differences for number of holes caused by Sitotroga cerealella attack in maize grains being lowest for Yellow T (43.3) and highest for PS-AZH-15 (P. vulgaris) (53.6). Number of adults was lowest for Yellow T and PS-AZH-15 and highest for Black T. Yellow T showed antixenoxis against Mythimna unipuncta and Sitotroga cerealella and can be used for partially controlling these maize pests. Furthermore, Yellow T was consistently superior to the control for both maize pests and could be used for future studies of maize protection; suggesting that there is a clear genetic regulation of this antixenotic effect. The protective mechanism has not insecticide properties; conversely, we believe that there could be substances that increase the hardness or reduce the palatability of tissues.