Year: 2021
Type: article
Abstract: Nyssaceae, consisting of 36 species in five genera (Camptotheca, Davidia, Diplopanax, Mastixia and Nyssa), are poorly known concerning their karyomorphology. Here we present karyomorphological features of seven species in all five genera and discuss chromosome evolution in the family. With a few dubious chromosome counts, information available shows that the chromosome number is consistent within a genus, i.e., 2n=42 in Campthotheca, Davidia and Diplopanax, 2n=44 in Nyssa, and 2n=26 in Mastixia. Their distribution on a phylogenetic tree suggests that 2n=42 is plesiomorphic with 2n=44 and 2n=26 apomorphic. Karyotype analyses show that 2n=42 of Camptotheca and Davidia comprise six sets of seven chromosomes, suggesting that Nyssaceae are of hexaploid origin with the basic number x=7.
Source: CYTOLOGIA
Authors: Kazuo Oginuma, Hiroshi Tobe
Institutions: University of Kochi, Kōchi University, Kyoto University
Language: English
Subfield: Genetics
Domain: Life Sciences
Open Access status: diamond
OpenAlex ID: W3136367064