Molecular and Cytological Studies of an Interspecific Hybrid in Schoenoplectus (Cyperaceae)
ITS sequence and chromosome data were used as evidence of natural hybridization in plants of Schoenoplectus (Cyperaceae) from Yawata moor, Hiroshima Prefecture, Japan. The hybrids were intermediate morphologically between both S. hotarui and S. gemmifer, and S. hotarui and S. triangulatus, and resembled S. ×trapezoideus. Chromosome numbers were observed to be 2n=76 for S. gemmifer, 2n=44 for S. hotarui, 2n=42 for S. triangulatus, and 2n=60 for the putative hybrid. The ITS sequence data showed that the hybrid had sequences from both S. gemmifer (2n=76) and S. hotarui (2n=44). Our cytological and ITS sequence results suggested that the putative hybrid with 2n=60 arose by natural hybridization between S. gemmifer (2n=76) and S. hotarui (2n=44).