Karyotype characterization and nuclear DNA content measurement in Bromeliaceae: state of the art and future perspectives.

Andrei C.P Nunes,Wellington R Clarindo

doi:10.1590/0001-3765201420140224

Abstract

In Bromeliaceae, cytogenetic and flow cytometry analyses have been performed to clarify systematic and evolutionary aspects. Karyotyping approaches have shown the relatively high chromosome number, similar morphology and small size of the chromosomes. These facts have prevented a correct chromosome counting and characterization. Authors have established a basic chromosome number of x = 25 for Bromeliaceae. Recently, one karyomorphological analysis revealed that x = 25 is no longer the basic chromosome number, whose genome may have a polyploid origin. Besides cytogenetic characterization, the 2C DNA content of bromeliads has been measured. Nuclear DNA content has varied from 2C = 0.60 to 2C = 3.34 picograms. Thus, in relation to most angiosperms, the 2C DNA content of Bromeliaceae species as well as their chromosome size can be considered relatively small. In spite of some advances, cytogenetic and flow cytometry data are extremely scarce in this group. In this context, this review reports the state of the art in karyotype characterization and nuclear DNA content measurement in Bromeliaceae, emphasizing the main problems and suggesting prospective solutions and ideas for future research.

Highlights

The Bromeliaceae family belongs to the order Poales (APG III 2009) and comprises about 58 genera and 3,170 species, distributed in tropical and subtropical regions of the American continent (Givnish et al 2011)
50% of the bromeliad species are found in Brazil, occurring in Atlantic Rainforest regions, Caatinga, montane savannas – ‘Campos Rupestres’, semi-arid regions and tropical savanna – ‘Cerrado’ (Ceita et al 2008)
Favoreto et al (2012) reported the nuclear DNA content and base composition (AT%) of 14 Bromeliaceae species, which ranged from 2C = 0.770 pg, for Billbergia horrida Regel, and 2C = 3.340 pg, for Tillandsia loliaceae Martius ex Schultes f

Summary

Introduction

The Bromeliaceae family belongs to the order Poales (APG III 2009) and comprises about 58 genera and 3,170 species, distributed in tropical and subtropical regions of the American continent (Givnish et al 2011). Apart from cytogenetic studies, flow cytometry (FCM) analyses have been performed to measure the nuclear DNA content and base composition (AT% and GC%) of different Bromeliaceae species, expanding the data about their genome. Cytogenetic studies in Bromeliaceae intended to establish the chromosome number.

Results

Conclusion