INVESTIGADORES
HONFI Ana Isabel
artículos
Título:
Chromosome studies in Orchidaceae from Argentina, II.
Autor/es:
GRABIELE MAURO; CERUTTI J.C.; HOJSGAARD D.H.; ALMADA R.D.; DAVIÑA J. R.; ANA I. HONFI
Revista:
TAXON
Editorial:
INT ASSOC PLANT TAXONOMY
Referencias:
Año: 2011 vol. 60 p. 1220 - 1221
ISSN:
0040-0262
Resumen:
ABSTRACT: Nine species of five genera of spiranthoid orchids from NE Argentina were chromosomally studied. All these terrestrial orchids share the chromosome number 2n = 46. Pelexia lindmanii Kraenzl (42m+4sm), P. bonariensis (Lindl.) Schltr. (36m+10sm), P. ekmanii (Kraenzl) Schltr. (36m+10sm), Sarcoglottis fasciculata (Vell.) Schltr. (32m+12sm+2st), S. grandiflora (Hook.) Klotzsch (32m+12sm+2st), S. ventricosa (Vell.)Hoehne (32m+12sm+2st), Mesadenella cuspidata (Lindl.) Garay (38m+8sm), Sacoila lanceolata (Aubl.) Garay (38m+8sm) and Skeptrostachys paraguayensis (Rchb. f.) Garay (38m+8sm) also share a bimodal and symmetrical karyotype configuration, with one or a few chromosome pairs relatively larger than the rest, many carrying the NORs and mean centromeric indexes decidedly metacentric, respectively. Additionally, a similar mean chromosome length (1.85±0.15 µm) and a comparable genome size (42.43±3.49 µm) are common features to all of them. These novel cytological evidences along with previous ones of this group support the conclusions of morphological and molecular approaches about the inclusion of Mesadenella Pabst & Garay, Pelexia Poit. ex Lindl., Sacoila Raf., Sarcoglottis C. Presl, and Skeptrostachys Garay within the subtribe Spiranthinae Lindl. Furthermore, the division of Spiranthinae in clades of lower rank, with Mesadenella, Sacoila, and Skeptrostachys in a group and Pelexia with Sarcoglottis segregating together is also supported by our cytological data in agreement with different approaches. Karyotype orthoselection processes may be accountable for the comparable karyotype features, particularly marked within Sarcoglottis and the group of Mesadenella, Sacoila, and Skeptrostachys.