These days, plant materials for the revegetation have been transported over the long distance in Japan. Because the plant materials have been carried with large quantities of soil and other plants, they must have been accompanied by many living things, including a wide range of insects. In this paper, we demonstrated that the evidence of the genetic divergence among five local populations of the small insect, Thrips nigropilosus, living on the one of the plant materials for the revegetation, Artemisia princeps; critical daylengths at 18°C for induction of the reproductive diapause and the brachypterous form in females of four populations, Wakkanai, Abashiri, Kyoto and Nagasaki populations, were between 11hrs and 14hrs and different from each other, whereas Naha population dose not show critical daylengths between 8hrs and 15hrs. Inter-population crosses between the local populations probably disturbe their genetic constructions. This possibly results in a decrease in the number of individuals in the population, because the diapause and the wing form are life history traits directly affecting the reproductive success. Thus, the transportation of the plant materials may disturbe genetic construction of local populations of living things. A general rule for the use of plant materials for the revegetation should be proposed.