A Karyological Study in Some Species of Coffea L. and in the Closest Relative Psilanthus travancorensis (Wight & Arn.) J.-F. Leroy

Abstract

Chromosome characterization were carried out in Coffea kapakata A. Chev (Bridson), C. racemosa Lour., C. salvatrix Swynn. & Philipson and in Psilanthus travancorensis (Wight & Arn.) J.-F. Leroy (2n=22) by employing the conventional acetic orcein technique as well as by C-and NOR-banding aiming further comparative studies. Although C. canephora and C. dewevrei have already been studied and depict a C-band karyotype, they have also been included for further comparisons, since NOR-banding and some other morphometric data have not been obtained yet. However, there were observed some differences among the species regarding chromosomal morphometry. The karyotype formula obtained was 3m+6sm+2sm s for C. salvatrix and P. travancorensis, 1M +2m + 6sm + 2sm s for C. kapakata and 2M +1m + 6sm + 2sm s for C. racemosa. All species displayed a moderate karyotype asymmetry and according to Stebbins system, C. canephora, C. dewevrei, C. kapakata and C. racemosa were classified as 3B while C. salvatrix and P. travancorensis were classified as 2A. Among the four indices used to assess karyotype asymmetry, Paszko AI index along with Stebbins were best suited to individualize the species. C-bands were preferentially situated at a pericentromeric/centromeric position. Two pairs of chromosomes, with secondary constriction and satellite segments, were observed in all the species following acetic orcein staining. C. racemosa and C. salvatrix showed NOR-band in both pairs, while only one chromosome pair carrying NOR-band was seen in C. canephora, C. dewevrei, C. kapakata and P. travancorensis. Data on chromosome morphometry, asymmetry indices and NOR-banding were suitable for the characterization of the species.

Karyotype Analysis Using C- and NOR-Banding in Ramie [<i>Boehmeria nivea</i> (L.) Gaud.]

“…The secondary constriction (SC) of mitotic chromosomes, however, was not C-banded. The absence of C-band formation in SC has already been reported in some other plants, e.g., Arachis and Coffea species (Pierozzi et al 2001(Pierozzi et al , 2012, which have chromosomes as small as ramie.…”

Karyomorphological study of five Turkish endemicRhaponticoidesVaill. (Asteraceae, Cardueae) species

“…It is reported that AI was seen to be quite informative in studies of infra-generic karyotypic heterogeneity, as demonstrated for eight Calamagrostis Adans. accessions (Poaceae) (Paszko 2006) and six Coffea L. species (Rubiaceae) (Pierozzi et al 2012). As demonstrated in the analysis of 217 species representing different Liliaceae genera (Peruzzi et al 2009), AI is perceived as a suitable parameter for suprageneric evolutionary studies (Rodrigues 2014).…”

Karyomorphology and karyotype asymmetry in the South American Caesalpinia species (Leguminosae and Caesalpinioideae)

“…These two asymmetry parameters have been adopted to analyze different taxonomic levels. AI was seen to be quite informative in studies of infra-generic karyotypic heterogeneity, as demonstrated for eight Calamagrostis accessions (Poaceae) (Paszko, 2006) and six Coffea species (Pierozzi et al, 2012). As demonstrated in the analysis of 217 species representing different Liliaceae genera (Peruzzi et al, 2009), AI is perceived as a suitable parameter for suprageneric evolutionary studies.…”

“…In both cases, these two parameters clarified the heterogeneity of karyotypes from all of the species analyzed. The scatter plot based on the variation sources comprising the AI is suitable to compare karyotypes of species from different taxa, as demonstrated in the analysis of different plant families (Paszko, 2006;Peruzzi et al, 2009;Pierozzi et al, 2012).…”