Karyotype studies in Lycium sections Schistocalyx and Sclerocarpellum (Solanaceae)

Abstract

Mitotic chromosomes numbers and karyotypes of five Argentinean and Chilean taxa were determined in 22 populations. Lycium ciliatum and the varieties of L. chilense analysed had diploid (2n = 24) as well as tetraploid (2n = 48) populations. Lycium ameghinoi was always diploid with 2n = 24. The suggested basic number x = 12 for the genus was confirmed. The chromosome number of L. chilense var. filifolium is reported for the first time and data on karyotype composition are mostly new. The karyotype of these taxa is highly symmetrical: the chromosomes are metacentric or submetacentric with the formula: 11 m + 1 sm. Microsatellites are present in chromosome pair #1 and are attached to the short arms. As found in other Lycium taxa explored so far, karyotypic features suggest that morphological differentiation in the group was not followed by chromosomal divergence.