IBONE   05434
INSTITUTO DE BOTANICA DEL NORDESTE
Unidad Ejecutora - UE
artículos
Título:
Evidence of 2n microspore production in a natural diploid population of Turnera sidoides subsp. carnea and its relevance in the evolution of the T. sidoides (Turneraceae) autopolyploid complex
Autor/es:
KOVALSKY IE, SOLÍS NEFFA VG
Revista:
Journal of Plant Research
Editorial:
Springer
Referencias:
Año: 2012 vol. 125
ISSN:
1618-0860
Resumen:
Abstract Turnera sidoides is a complex of distylous
perennial rhizomatous herbs that includes five subspecies.
Since polyploidy has played a prominent role within this
species (x = 7), ongoing studies in T. sidoides are focused
on the understanding of the mechanisms involved in the
origin and the establishment of polyploids. Therefore,
aiming to contribute to the understanding of the mode of
polyploid formation, in this study we investigated the frequency
of unreduced microspores in a natural diploid
population of T. sidoides subsp. carnea by analyzing the
size range of pollen and the constitution of the sporads. The
results showed that some of the individuals studied
produced 2n and 4n microspores, both in short- and
long-styled floral morphs. The analysis performed documents
the production of unreduced microspores in T. sidoides
subsp. carnea and provides evidence that support the
hypothesis of sexual polyploidization as one of the most
probable mechanisms involved in the origin of polyploids
within this species complex. The role of unreduced pollen
in the establishment and persistence of newly formed
polyploids in diploid populations of T. sidoides is also
discussed.