Cytogenetics of some species and natural hybrids in Prosopis (Leguminosae)

J.H. HUNZIKER, L. POGGIO, C.A. NARANJO, R.A. PALACIOS AND A. B. ANDRADA

CANADIAN JOURNAL OF GENETICS AND CYTOLOGY

Canadian journal of genetics and cytology

Lugar: Canada; Año: 1975 vol. 17 p. 253 - 262

0008-4093

Cytological results on 12 species and 4 putative hybrids of Prosopis are presented. of these, 5 species and 4 hybrids have been hitherto unknown cytologically. The following species proved to be diploid (2n=28) and constitute new chromosome number determinations for the genus: P. algarobilla Griseb., P. hassleri Harms, P. nigra (Griseb.) Hieron., P. patagonica Speg., P. tamarugo Phil. The diploid nature of some races of P. juliflora (Sw.) DC. is established; apparently under this taxon there are also tetraploid populations. The following putative interspecific hybrid showed regular meiosis with formation of 14 bivalents: P. vinalilo Stuck. (P. ruscifolia x P. alba?), P. alba x P. nigra? and P. hassleri x P. ruscifolia?. So far 28 taxa of the genus have been studied cytologically; 27 of these are diploid. The scarcity of polyploidy in the genus (3.5%) might be a consequence of the almost general lack of means of vegetative reproduction and of the absence of chromosome repatterning in primary speciation. Results of other authors concerning cytological data are also discussed.