Estudios cromosómicos en dos especies de Cordia Argentina (Boraginaceae)

LAS PEÑAS M. L.

BOLETíN DE LA SOCIEDAD ARGENTINA DE BOTáNICA

Lugar: Córdoba; Año: 2003 vol. 38 p. 319 - 323

0373-580X

The somatic chromosomes of Cordia ecalyculata and C. trichotoma (Boraginaceae). The mitotic chromosome numbers are reported for the first time for two Cordia species (Boraginaceae) from Argentina. Cordia ecalyculata Vell. (section Pilicordia, ?gomita?) was 2n = 28 (x = 7). The chromosomes were small (average length 3.0 ìm). The haploid genome length was 41,6 ìm. The slightly asymmetric karyotype was composed of: 4 m + 10 sm + 14 st chromosomes, with satellites in the first sm chromosome pair. The asymmetry indices were A1 : 0.8 and A2: 0.07. The basic number suggested for C. ecalyculata agrees with the basic number of the corresponding section. This fact supports the actual taxonomic position of C. ecalyculata. The chromosome number of Cordia trichotoma (Vell.) Arrab. ex Steud (section Gerascanthus, ?peterivy?) had 2n = 104. The chromosomes were small (with an average length of 1.50 ìm). The genome length 79 ìm.Cordia ecalyculata and C. trichotoma (Boraginaceae). The mitotic chromosome numbers are reported for the first time for two Cordia species (Boraginaceae) from Argentina. Cordia ecalyculata Vell. (section Pilicordia, ?gomita?) was 2n = 28 (x = 7). The chromosomes were small (average length 3.0 ìm). The haploid genome length was 41,6 ìm. The slightly asymmetric karyotype was composed of: 4 m + 10 sm + 14 st chromosomes, with satellites in the first sm chromosome pair. The asymmetry indices were A1 : 0.8 and A2: 0.07. The basic number suggested for C. ecalyculata agrees with the basic number of the corresponding section. This fact supports the actual taxonomic position of C. ecalyculata. The chromosome number of Cordia trichotoma (Vell.) Arrab. ex Steud (section Gerascanthus, ?peterivy?) had 2n = 104. The chromosomes were small (with an average length of 1.50 ìm). The genome length 79 ìm.