Chromosomal Criteria and Taxonomic Relationships in the Solanaceae

Abstract

Taxonomic relationships in the Solanaceae have been discussed based on chromosomal criteria of forty five species; including three new records; belonging to fifteen genera representing eight of the fourteen currently recognized tribes; and their phylogeny based on variation in chromosome number is proposed. In contrast to the traditional subfamilial delimitation of the family (Murray, 1945; D'Arcy, 1979; 1991; Armstrong, 1986) cytological data indicate that subfamily Cestroideae is less evolved than subfamily Solanoideae. These data further support the isolation of Cestrum in a separate tribe. The isolation of tribe Salpiglossideae in a separate family as proposed by Hutchinson (1973) and the delimitation of both Datura and Hyoscayamus as two separate tribes as done by D'Arcy, (1991) is strongly supported by cytological data. In agreement with both Wettstein (1895) and D'Arcy (1991) the delimitation of Nicandra in a separate tribe is further recommended. However, the separation of Atropa and Lycium from the tribe Solaneae are not likely to be justified based on cytological ground.