Mitotic behavior in root tips of Brachiaria genotypes with meiotic chromosome elimination during microsporogenesis.

Departamento de Biologia Celular e Genética, Universidade Estadual de Maringá, Maringá, PR, Brasil.
Genetics and molecular research: GMR (Impact Factor: 0.99). 02/2008; 7(2):336-41. DOI: 10.4238/vol7-2gmr437
Source: PubMed

ABSTRACT Three accessions of Brachiaria brizantha, three of B. humidicola, and two interspecific hybrids between B. ruziziensis and B. brizantha were analyzed with regard to their mitotic behavior in root tips. All these genotypes revealed chromosome elimination or lack of chromosome affinity in previous analyses of microsporogenesis. Analyses of root tips showed a normal mitotic division in all accessions and hybrids, reinforcing the notion that the genetic control of meiosis is totally independent of that of mitosis. The implications of these findings for the Brachiaria breeding program are discussed.

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