Towards male sterility in Cryptomeria japonica using the male strobilus-specific genes of C. japonica

Background Cryptomeria japonica D. Don (sugi) is one of the most important Japanese conifer species. Rapid improvement of the wood trait (e.g., growth speed and wood quality) using a conventional breeding approach is not possible, because breeding of coniferous tree requires a very long time. Genetic modification might be a powerful tool to shorten the time needed to breed trees compared with traditional breeding methods because it is able to induce the favorable traits by introduction of specific genes in trees without unnecessary genetic transitions. But the transfer of foreign genes from GM plants to related plant species by pollen has been cited as an environmental concern. For the purpose of creating male sterile GM C. japonica, we attempted to identify genes related to male flower formation.