Abstract
Defensive secretions and hydrocarbons of Tribolium freemani, T. castaneum and their hybrids were analysed by GLC and GC-MS. The combination of the parent species affected strongly the chemistry of the secretions and the hydrocarbons of the hybrids. The secretions of the parent species were similar to each other, and hybrid-(I) from T. freemani (♀)×T. castaneum (♂) produced simple mixtures of the parental secretions, whereas hybrid-(II) from the reverse sex combination of the parents gave the same composition as that of T. castaneum. In the hydrocarbons, however, fairly large differences were present between the parents and their hybrids, although those of the parents were very similar to each other. n-Nonacosane was the most abundant hydrocarbon of the parents, whereas 11+13-methylheptacosane was the richest component of the hybrids. A small difference was also found between the two hybrids. Both n-pentacosane and 3-methylpentacosane in hybrid-(I) were about ten times more abundant than in hybrid-(II).
