Abstract: The plant secondary metabolites contribute to the plant defenses bases, so the genetic result on the secondary metabolites of recent decades is summarized in the paper. As other traits, the variation of plant secondary metabolites is under genetic control too. In most case, the production of secondary compound is the result of the coordinated action of a multitude of enzymes along a pathway, so the phenotype of compounds show quantitative fashion and under multigenic or polygenic control. Because of the inevitable linkages between primary metabolism and secondary, there are limits on chemical variability. Certain kind of compound is effective to certain insect species even subspecies only, so the chemical insect resistance means specific resistance and is complicated. By recent advances in molecular genetics and biotechnology, the development of quantitative genetics and insect resistance breeding got new advance. As most of the phytochemical characters are inherited in quantitative fashion and regulated by polygenes, by using the quantitative trait loci (QTLs) technique, the progress about the phytochemical mediated insect resistance were made, the details are given by Illustrating with main crops.

Key words: Genetics, Secondary metabolites, Pest-resistance, Quantitative trait loci