Resumo

FRAYSSINET, N. et al. ESTUDIO CITOLÓGICO, EXO Y ENDOMORFOLÓGICO EN ATRIPLEX LAMPA (MOQ.) D. DIETR. (CHENOPODIACEAE). Polibotánica [online]. 2007, n.24, pp.1-23. ISSN 1405-2768.

Atriplex lampa (Moq.) D. Dietr. is a halophytic, dioecious shrub native to Patagonia, Argentina. Although relatively neglected by science, it is important for sand-stabilization and for biomass and fodder production due to its nutritional characteristics and acceptable percentage of gross protein.

The objective of this study is to provide cytological and morpho-anatomical information about A. lampa, which could be useful when applied in recovery and repopulation plans intending to use this species in areas degraded by petroleum industry activity.

Natural populations in the Province of Chubut (45°-46° S; 67°- 68° W), Argentina, were studied. Karyotypes and meiotic behavior were analyzed according to conventional protocols, as were anatomical and morphological comparisons. Analysis of variance was used to test morphometrical differences between populations and cytotypes. Voucher specimens are deposited at the Facultad de Ciencias Naturales, Universidad Nacional San Juan Bosco de Patagonia, Argentina.

Our results show that A. lampa has two cytotypes: diploids (2n = 2x = 18) and tetraploids (2n = 4x = 36). The stems and roots have anomalous secondary growth, and the leaves are amphistomatic, with a Kranz structure, and are covered with dense glandular trichomes. The leaves and fruit bracteoles are different sizes in the two cytotypes.

Palavras-chave : Atriplex lampa; cytogenetics; autopolyploid morphoanatomical variation; Patagonia; Argentina.

        · resumo em Espanhol     · texto em Espanhol     · Espanhol ( pdf )