Plant systematics; Karyotype and genome evolution; Polyploidy; Accessory genetic material (B-chromosomes and supernumerary segments - origin and evolution); Molecular cytogenetics; Plant breeding systems.
Systematics and chromosomal evolution in flowering plants
Plants exhibit diverse speciation, and can be characterized by the evolution between closely related species. One of the most important views as adaptive force for plant speciation is hybridization, which can lead to an increase in genetic diversification with potential source in the evolutionary history of new species, and polyploidization, which is accompanied by rapid genetic changes as well as gene expression and phenotypic variation. Although both hybrids and polyploids suffer from numerous chromosomal rearrangements and more subtle changes in sequence composition, they still continue to generate species diversity for contributing to speciation events. The ultimate aims of the ongoing research in the lab are (1) to obtain cytogenetically derived hypotheses on extent, dynamics, and mechanisms involved in chromosomal evolution and diversification in flowering plants; and (2) not only to test a phylogenetic context based on molecular and morphological characters to assess the importance of plant evolution but also to understand the role of chromosomal changes between intraspecific lineages; and (3) to thoroughly investigate the chromosomal features based on molecular cytogenetic approaches.
Evolutionary consequence of flowering plant breeding systems
Male sterility is a common feature in the evolution of plant breeding systems such as gynodioecy and dioecy, and it has been of great interest to evolutionary biologists. Gynodioecy is a breeding system in which populations contain females and hermaphrodites. Although gynodioecy has evolved independently several times in flowering plants, it is considered to be a rare and unstable outbreeding system. To elucidate the breeding system, floral morphological, micromorphological characters as well as internal structures in floral organs by using scanning electron microscopy (SEM) could be potential values for understanding the evolutionary significance in flowering plants.