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Genetic evidence of an internal deletion induced by B chromosomes in maize (Zea mays L.)

Luiz Sérgio Saraiva; Carlos Roberto de Carvalho

Departamento de Biologia Geral, Universidade Federal de Viçosa, 36570-000 Viçosa, MG, Brasil

ABSTRACT

B chromosomes were used to induce deficiencies in the short arm of chromosome 9 of maize (Zea mays L.). One chromosome with a small terminal deficiency also possessed an internal deletion whose presence was revealed by several genetic tests. Although internal deletion is not predicted by the high-loss mechanism, breaks in the A chromosomes are frequent and occasional recovery of unusual structural modifications may occur.

Keywords: Deletion; B chromosomes; Zea mays.

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