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Preparation of mitotic chromosomes of leaf-cutting ants from the genera Atta and Acromyrmex

 

 

M.C. Santos-ColaresI; J. ViégasI; M.G. Martino RothI; A.E. LoeckII

ILaboratório de Biologia Celular CPACT/UFPeI, Departamento de Zoologia e Genética, Instituto de Biologia, Universidade Federal de Pelotas (UFPeI), Campus Universitário s/n. 96010-900 Pelotas, RS, Brasil. Tel: (0532) 75-7340; Fax: (0532) 75-7169. Send correspondence to J.V.
IIDepartamento de Fitossanidade, Faculdade de Agronomia Eliseu Maciel, UFPeI, Pelotas, RS, Brasil.

 

 

ABSTRACT

Some modifications were made to the methodology of Imai et al. (Jpn. J. Genet. 63: 159-185, 1988) for cytogenetic analysis of the leaf-cutting ants Atta sexdens piriventris and Acromyrmex heyeri (Hymenoptera, Formicidae), shortening preparation time and improving chromosomal preparations. The brain ganglia of prepupae were dissected in a 0.0025% hypotonic solution of colchicine, placed on a glass slide on a cold plate (4 ± 1°C) for 20 min. The material was fixed directly on the cold slide (with cold fixative I), macerated with a histological needle and fixed again with fixative I, followed by fixatives II and III, all of them cold. The slide was flame-dried right after the use of fixative III, and it was allowed to air-dry at room temperature for 2 h. The resulting metaphases presented less contracted chromosomes, with separated and well defined sister chromatids at a high frequency, when the material was processed in the manner described and stained with 3% Giemsa in phosphate buffer (pH 6.8) for 15 min.

Keywords: mitotic chromosomes methodology; Atta.

 

 

REFERENCES

Fadini, M.A. and Pompolo, S.G. (1993). Citogenética em espécies de formigas da tribo Attini da região de Viçosa, MG. Resumo. Rev. Bras. Genet. 16 (Suppl): 181.

Fadini, M.A. and Pompolo, S.G. (1996). Cytogenetics of some ant species of the tribe Attini (Hymenoptera, Formicidae) from the region of Viçosa, MG. Braz. J. Genet. 19: 53-55.

Goñi, G., Zolessi, L.C. and Imai, H.T. (1983). Karyotype of thirteen ant species from Uruguay (Hymenoptera - Formicidae). Caryologia 36: 363-371.

Imai, H., Taylor, R.W., Crosland, M.W. and Crozier, R. (1988). Modes of spontaneous chromossomal mutation and karyotype evolution in ants with reference to the minimum interaction hypothesis. Jpn. J. Genet. 63: 159185.

Santos, M.C., Viégas, J., Loeck, A.E. and Roth, M.G.M. (1993). Análise do cariótipo da formiga cortadeira Atta sexdens piriventris. IV Simpósio Internacional sobre Formigas- Praga, Belo Horizonte, MG, pp. 21.