Karyotype polymorphism of GC-rich constitutive heterochromatin in Capsicum L. pepper accessions

Abstract

Capsicum is represented by peppers and sweet peppers and comprises a group with remarkable genetic variability. Different cultivated Capsicum peppers of Brazil were evaluated by using CMA 3 and DAPI specific fluorochromes. There was high polymorphism of highly GC-rich CMA heterochromatic bands among the analyzed species, ranging from six (BAGC 114; C. annuum) to 26 blocks (BAGC 81; C. baccatum). Heterochromatin percentage ranged from 3.14% (BAGC 114; C. annuum) to 8.72% (BAGC 81; C. baccatum), corroborating the variation in the number of heterochromatic bands, particularly those distributed in the terminal and subterminal regions of the chromosomes. The information reported in this paper supports the cytogenetic characterization of the domesticated peppers accessions belonging to the Capsicum Germplasm Active Bank of the Federal University of Piauí (BAGC-UFPI). Moreover, the present data helped to better understand the karyotype features of peppers and provide additional information that could contribute to the improvement and maintenance of Capsicum genetic breeding programs.

Genetics and Genomics of Capsicum: Valuable Resources for Capsicum Development

“…In 12 Capsicum accessions, a chromosome number of 2n = 2x = 24 was determined, and this ploidy level is well-documented in several Capsicum species [17]. Capsicum species in the wild, such as C. buforum, has a ploidy level of 2n = 2x = 26 [17]. Two distinct evolutionary lines emerged throughout the history of this genus, marked by a significant separation between wild (base number x = 13) and domesticated (base number x = 12) species [17].…”

“…In 12 Capsicum accessions, a chromosome number of 2n = 2x = 24 was determined, and this ploidy level is well-documented in several Capsicum species [17]. Capsicum species in the wild, such as C. buforum, has a ploidy level of 2n = 2x = 26 [17].…”

“…Capsicum species in the wild, such as C. buforum, has a ploidy level of 2n = 2x = 26 [17]. Two distinct evolutionary lines emerged throughout the history of this genus, marked by a significant separation between wild (base number x = 13) and domesticated (base number x = 12) species [17]. Multiple karyotypic formulae in the same species may occur from genetic variances within populations, which are produced by genomic responses to various environments [17].…”

“…Two distinct evolutionary lines emerged throughout the history of this genus, marked by a significant separation between wild (base number x = 13) and domesticated (base number x = 12) species [17]. Multiple karyotypic formulae in the same species may occur from genetic variances within populations, which are produced by genomic responses to various environments [17]. Individuals in the same group might have different chromosomal races due to chromosomal polymorphism [17].…”

“…Multiple karyotypic formulae in the same species may occur from genetic variances within populations, which are produced by genomic responses to various environments [17]. Individuals in the same group might have different chromosomal races due to chromosomal polymorphism [17].…”