Incremento del numero cromosomico e comparsa di B-cromosomi durante l'allevamento in laboratorio di una popolazione diploide di Dugesia benazzii (triclade paludicolo)
Deri, Paolo
Atti della Accademia Nazionale dei Lincei. Classe di Scienze Fisiche, Matematiche e Naturali. Rendiconti, Tome 68 (1980), p. 327-332 / Harvested from Biblioteca Digitale Italiana di Matematica
Access to full text
Full (PDF)
Full (DjVu)

This paper reports on the chromosome variations which occurred during a prolonged laboratory culture in specimens of the freshwater planarian Dugesia benazzii collected in the river Cavo (Corsica). In natural conditions, as well as in the first period of culture (1968-1970), all individuals were sexual and eudiploid in both somatic and germ cells. In 1971-1972, however, they became agamic and fissiparous. Their somatic cells showed a hyperdiploid complement of 19-26 chromosomes, which appeared homologous to the ones of the standard set of the species (A-chromosomes). More recently, B-chromosomes in a number of 1-3 and morphologically similar to those already described by the A. in other natural populations from Corsica, have been observed in 85% of the hyperdiploid somatic cells. The origin of polysomy and the mechanism of its transmission as well as the factors determining the appearance of the B-chromosomes in this strain are still unknown. The increase in chromosome number preceded the appearance of B-chromosomes, but a causal relationship between these two events is not ascertained. It is also worthy of attention that these karyological variations occurred after a long period of laboratory culture and at the time that fissioning was acquired. Aneuploidy has been frequently observed in fissiparous species of the "D. gonocephala group"; however, the correlation between these two phenomena is not constant and probably depends on specific genetic factors.

Publié le : 1980-04-01
@article{RLINA_1980_8_68_4_327_0,
     author = {Paolo Deri},
     title = {Incremento del numero cromosomico e comparsa di B-cromosomi durante l'allevamento in laboratorio di una popolazione diploide di Dugesia benazzii (triclade paludicolo)},
     journal = {Atti della Accademia Nazionale dei Lincei. Classe di Scienze Fisiche, Matematiche e Naturali. Rendiconti},
     volume = {68},
     year = {1980},
     pages = {327-332},
     language = {it},
     url = {http://dml.mathdoc.fr/item/RLINA_1980_8_68_4_327_0}
}

Deri, Paolo. Incremento del numero cromosomico e comparsa di B-cromosomi durante l'allevamento in laboratorio di una popolazione diploide di Dugesia benazzii (triclade paludicolo). Atti della Accademia Nazionale dei Lincei. Classe di Scienze Fisiche, Matematiche e Naturali. Rendiconti, Tome 68 (1980) pp. 327-332. http://gdmltest.u-ga.fr/item/RLINA_1980_8_68_4_327_0/

Benazzi, M. (1960) - «Acc. Naz. Lincei: Evoluzione e Genetica», Quaderno 47, 273-296.

Benazzi, M. (1969) - «Rend. Acc. Naz. Lincei», ser. VIII, 46, 605-609.

Benazzi Lentati, G. (1957) - «Caryologia», 10, 352-387.

Benazzi Lentati, G. (1964) - «Atti Soc. Tosc. Sci. Nat.», Mem., ser. B, 71, 44-51.

Benazzi Lentati, G., Curini, A. e Piegaja, M.I. (1951) - «Atti Soc. Tosc. Sci. Nat.», Mem., ser. B, 58, 85-93.

Benazzi Lentati, G. e Deri, P. (1977) - «Rend. Acc. Naz. Lincei», ser. VIII, 62, 847-851.

Bromley, H.J. (1974) - «Zool. Scripta», 3, 239-242.

Conger, A.D. e Fairchild, L.M. (1953) - «Stain Technol.», 28, 281-283.

Deri, P. (1971) - «Atti Soc. Tosc. Sci. Nat.», Mem., ser. B, 78, 55-74.

Deri, P. (1975) - «Atti Soc. Tosc. Sci. Nat.», Mem., ser. B, 82, 25-38.

Kawakatsu, M., Oki, I., Tamura, S. e Sugino, M. (1976) - «Bull. Fuji Women's Coll.», 14, 81-126.

White, M.J.D. (1973) - Animal Cytology and Evolution. 3rd Edition. Cambridge University Press. | MR 2358923