Abstract
Cross-attraction among three Tribolium species, T. freemani, T. castaneum and T. confusum, and F1 hybrids between the former two species was investigated using their aggregation pheromones. It was confirmed that (i) the male pheromone of Hybrid-I (hybrids between T. freemani (♀)×T. castaneum (♂)) was active to T. castaneum, but inactive to T. freemani and T. confusum; (ii) the pheromone of Hybrid-II (hybrids between the reciprocal sex combination) attracted the two species but not T. confusum; (iii) Hybrid-I was attractive to the parent species but not to T. confusum; (iv) Hybrid-II responded to all three species; and (v) the two hybrids were attractive to each other.
