Abstract

RODRIGUES, Rodrigo Schütz; CORREA, Andréa Macêdo; FORNI-MARTINS, Eliana  and  TOZZI, Ana Maria Goulart de Azevedo. Chromosome numbers in species of Acosmium Schott and Leptolobium Vogel (Leguminosae, Papilionoideae). Acta Bot. Bras. [online]. 2009, vol.23, n.3, pp. 902-906. ISSN 0102-3306.  http://dx.doi.org/10.1590/S0102-33062009000300031.

A cytotaxonomic analysis of species of Acosmium Schott e Leptolobium Vogel was carried out, by determining their chromosome numbers. The three species of Acosmium and five species of Leptolobium (representing 50% of the genus) were studied from seeds obtained from different regions of Brazil. Chromosome counts were new for all Acosmium species and for four Leptolobium species. For Acosmium cardenasii, 2n = 18 was constantly observed, while occurring at the same meristem were found 2n = 18, 24 e 32 in A. diffusissimum and 2n = 18 e 32 in A. lentiscifolium. For Leptolobium, all studied species had 2n = 18, confirming a previous count for L. dasycarpum. The results showed that chromosome numbers of Acosmium and Leptolobium species are homogeneous, confirming the basic number x = 9 for both genera. Therefore, chromosome numbers do not provide a useful taxonomic character distinguishing Acosmium from Leptolobium.

Keywords : aneussomaty; genistoid clade; mosaicism; Sophoreae; taxonomy.