Chromosome numbers in Bromeliaceae

Abstract

The present study reports chromosome numbers of 17 species of Bromeliaceae, belonging to the genera Encholirium, Bromelia, Orthophytum, Hohenbergia, Billbergia, Neoglaziovia, Aechmea, Cryptanthus and Ananas. Most species present 2n = 50, however, Bromelia laciniosa, Orthophytum burle-marxii and O. maracasense are polyploids with 2n = 150, 2n = 100 and 2n = 150, respectively, while for Cryptanthus bahianus, 2n = 34 + 1-4B. B chromosomes were observed in Bromelia plumieri and Hohenbergia aff. utriculosa. The chromosome number of all species was determined for the first time, except for Billbergia chlorosticta and Cryptanthus bahianus. Our data supports the hypothesis of a basic number of x = 25 for the Bromeliaceae family and decreasing aneuploidy in the genus Cryptanthus.<br>Este trabalho apresenta o número de cromossomos de 17 espécies de Bromeliaceae, pertencentes aos gêneros Encholirium, Bromelia, Orthophytum, Hohenbergia, Billbergia, Neoglaziovia, Aechmea, Cryptanthus e Ananas. A maioria tem cariótipo 2n = 50, mas Bromelia laciniosa, Orthophytum burle-marxii e O. maracasense são poliplóides com 2n = 150, 100 e 150, respectivamente, enquanto Cryptanthus bahianus tem 2n = 34 + 1-4B. Cromossomos B foram observados também em Bromelia plumieri e Hohenbergia aff. utriculosa. O número de cromossomos de todas as espécies foi determinado pela primeira vez, exceto para Billbergia chlorosticta e Cryptanthus bahianus. Os dados obtidos reforçam a hipótese de um número básico x = 25 para a família Bromeliaceae e aneuploidia decrescente no gênero Cryptanthus

Chromosome Number for Bromeliaceae Species Occurring in Brazil

“…All the species presented a diploid number 2nϭ50, except for Orthophytum albopictum and Neoglaziovia variegata, which are tetraploids, 2nϭ100 ( (Lindschau 1933, Sharma and Ghosh 1971, Brown et al 1984, Varadarajan and Brown 1985, Brown and Gilmartin 1986, 1989, Marchant 1967, Brown et al 1997, Baracho and Guerra 2000, Gitaí et al 2000, Cotias de Oliveira et al 2000. These counts showed nϭ25, 2nϭ50 in about 68 species analyzed and only five polyploids with 2nϭ100, 150.…”

“…al. 1984, Brown and Gilmartin 1989, Brown et al 1997, Baracho and Guerra 2000, Gitaí et al 2000, Cotias de Oliveira et al 2000, Palma-Silva 2003. The majority of the 101 species counts have been nϭ25.…”

“…The most primitive members of the Pitcairnioideae and Tillandsioideae subfamilies are found in the northern region of Andean Mountains to Mexico and the Antilles, while the eastern part of Brazil has the most advanced species of the Bromelioideae subfamily, and the evolved species from the genera Dyckia from Pitcairnoideae and Vriesea from Tillandsioideae (Smith 1934, Leme andMarigo 1993). The cytogenetic analyses of the Bromeliaceae comprise approximately 12% of known species, with the majority being cultivated ornamental (Lindschau 1933, Weiss 1965, Gauthé 1965, Marchant 1967, Sharma and Ghosh 1971, McWilliams 1974, Brown et al 1984, Varadarajan and Brown 1985, Brown and Gilmartin 1986, 1989, Lin et al 1987, Brown et al 1997, Baracho and Guerra 2000, Gitaí et al 2000, Cotias de Oliveira et al 2000, Palma-Silva 2003. The first chromosome counts revealed great variation with 2nϭ48, 50, 56, 64, 72, 94, 96, 100 and 126, and contradictory interpretations on its basic number.…”

Chromosome number of Orthophytum species (Bromeliaceae)

“…In the Bromeliaceae, cytogenetic studies are rare and chromosome numbers have been reported for no more than 12% of the species (Lindschau 1933;Gauthé 1965;Weiss 1965;Marchant 1967;Sharma & Ghosh 1971;McWilliams 1974;Brown et al 1984;Varadarajan & Brown 1985;Brown & Gilmartin 1986, 1989Lin et al 1987;Brown et al 1997;Cotias-de-Oliveira et al 2000Ramírez-Morillo & Brown 2001;Palma-Silva et al 2004;Bellintani et al 2005;Gitaí et al 2005). The chromosomes are small with sizes varying between 0.23 mm and 1.5 mm (Cotias-de-Oliveira et al 2000;Ceita et al 2008).…”

“…Nowadays, all studies based on meiotic (Brown & Gilmartin 1983, 1986, 1989Brown et al 1997;Palma-Silva et al 2004 Chromosome numbers have been reported for only six species of Orthophytum, revealing an euploid series (i.e. polyploids in exact multiples of the basic number) of 2n = 2x = 50, 2n = 4x = 100 and 2n = 6x = 150 chromosomes (Ramírez-Morillo & Brown 2001;Cotias-de-Oliveira et al 2000Bellintani et al 2005;Gitaí et al 2005). Polyploidy, or genomic duplication, is a common and continuous phenomenon in plant evolution, and about 70% of the angiosperms are polyploids (Leitch & Bennett 1997).…”