Estudios citotaxonómicos en especies de Argemone

Abstract

Lozzia, María E.; Aldo R. Andrada y María E. Cristóbal, 2006. ?Citotaxonomic studies in species of Argemone?. Lilloa 43 (1-2). Argemone (Fam. Papaveraceae) is an American genus with great diversity in their morphological characteristics which have originated controversy. A population of the named ?holy thistle? was citogenetically and morphologically analyzed. Four taxa have been distinguished by their fruits and flowering colours. They were denominated: types I, II, III and IV which present chromosomal numbers and a different meiotic behaviour. The morphological characteristics observed in fresh material have allowed to homologate these types with those descripted in previous works: type I = A. mexicana, type II = A. subfusiformis, type III = A. ochroleuca, type IV = Argemone sp. The cytological observations let us to recognize the following: A. mexicana as a diploid with n = 14, type II as a hexaploid with n = 42 with a regular meiosis, type III as a triploid with n = 18-20 with an meiosis irregular with trivalent and univalent chromosomes, the type IV as a triploid with n = 19-23 with a very irregular meiosis, sterile pollen, scarce seeds. The last three recounts were known for the first time.