Karyomorphology and Its Evolution in Dipterocarpaceae (Malvales)

抄録

Previous chromosome information is restricted to Dipterocarpoideae, one of the two subfamilies of Dipterocarpaceae, and no chromosome information is available for another subfamily Monotoideae. Here we present the first karyomorphology of Marquesia macroura (2n=22) (Monotoideae), as well as of four species (2n=22) of four genera in tribe Dipterocarpeae and five species (2n=14) of tribe Shoreae in Dipterocarpoideae. Comparisons within Dipterocarpaceae and with Sarcolaenaceae (2n=22) sister to Dipetrocarpaceae in the light of phylogenetic relationships show that the basic chromosome number x=11 is plesiomorphic and x=7 apomorphic in Dipterocapaceae. Based on available information, tribe Shoreae (x=7) has a uniform karyotype where all chromosomes have a centromere at median position, while the rest of the family (x=11) have a diverse karyotype in terms of the frequency of chromosomes with a centromere at median, submedian and subterminal position. We discussed the meaning of lability of karyotype in chromosome evolution.