A study of DNA nuclei content was made in eight species of the South American genus Bulnesia using interphase epidermal and telophase root apex nuclei. Among diploid species (2n = 26) B. retama (2.269 plcograms (pg) per genome) has six times more DNA than B. sarmientol (0.362 pg per genome), 1.6 times more than its closely related species, B. chllensis, and 4 to 5 times more than the other species studied. The differences in DNA are correlated with changes in karyotype morphology and chromosome size. Octoploid B. bonariensis (2n = 104) shows by far the smaller DNA content per average basic genome (0.276 pg) and has the smallest chromosomes. The species with the highest DNA content, B. retama and B. chilensis, also have the highest constitutive heterochromatin content as revealed by C-banding and measurements of the heterochromatin area in prophase nuclei. Considering the percentage of heterochromatin of B. retama as 100 percent, evaluated on the basis of the chromocenter area in interphase, B. chllensis has 68 percent, B. bonariensis, B. follosa, and B. schickendantzil have between 10 percent and 15 percent, and B. sarmientol has about 4 percent. The possible origin of the extraordinary interspecific differences in DNA content and their evolutionary implications are discussed. © 1986, American Genetic Association.
Documento: | Artículo |
Título: | Nuclear dna content variation in Bulnesia |
Autor: | Poggio, L.; Hunziker, J.H. |
Filiación: | Departamento de Ciencias Biológicas, Facultad de Ciencias Exactas y Naturales, 1428 Buesnos Aires, Argentina Carrera del Investigador Cientifico, Instituto de Botánica Darwinion, Casilla de Correo 22, 1642 San Isidro, Argentina Universidad de Buenos Aires, Argentina |
Idioma: | Inglés |
Año: | 1986 |
Volumen: | 77 |
Número: | 1 |
Página de inicio: | 43 |
Página de fin: | 48 |
Título revista: | Journal of Heredity |
Título revista abreviado: | J. Hered. |
ISSN: | 00221503 |
CODEN: | JOHEA |
Registro: | https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_00221503_v77_n1_p43_Poggio |