EFFICIENCY OF CYTOGENETIC METHODS IN DETECTING A CHROMOSOME REARRANGEMENT INDUCED BY IONIZING RADIATION IN A CULTIVATED CHILI PEPPER LINE (CAPSICUM BACCATUM VAR. PENDULUM-SOLANACEAE)

SCALDAFERRO, M. A.; GRABIELE M.; SEIJO, J. G.; DEBAT, H. J.; ROMERO, M. V.; DUCASSE, D. A; PRINA, A. R.; MOSCONE, E. A.

INTERNATIONAL JOURNAL OF RADIATION BIOLOGY

TAYLOR & FRANCIS LTD

Lugar: Londres; Año: 2014 vol. 90 p. 104 - 112

0955-3002

Purpose: The present study was designed to locate transient chromosome aberrations on a selected pepper cultivar and determine the tracing efficiency of different cytogenetic methods. Materials and methods: Seeds from Capsicum baccatum var. pendulum cultivar ?Cayenne? were treated with an acute dose of X-rays (300 Gy) and chromosome aberrations were analysed by different cytogenetic methods [Feulgen, silver staining for nucleolus organizer regions (AgNOR), fluorescent banding, fluorescence in situ hybridization (FISH) and meiotic analysis]. Results: A rearranged chromosome carrying two nucleolus organizing regions (NOR) induced by ionizing radiation was detected in the cultivar, with the occurrence of a small reciprocal exchange between a chromosome of pair no. 1 and another chromosome of pair no. 3, both carrying active NOR in short arms and associated chromomycin positive / diamidino - phenylindole negative (CMA+/DAPI-) heterochromatin. Meiotic analysis showed a quadrivalent configuration, confirming a reciprocal translocation between two chromosomes. Conclusions: The use of X-ray in Capsicum allowed us to develop and identify a pepper line with structural rearrangements between two NOR-carrying chromosomes. We postulate that all the cytological techniques employed in this research were efficient in the search for chromosome aberrations. Particularly, Feulgen and AgNOR were the most suitable in those cases of transient rearrangements, whereas fluorescent banding and FISH were appropriate for intransitive ones.