Abstract

SANTOS, Carlos Antonio Fernandes; LEITE, Daniela Lopes; OLIVEIRA, Valter Rodrigues  and  RODRIGUES, Marciene Amorim. Marker-assisted selection of maintainer lines within an onion tropical population. Sci. agric. (Piracicaba, Braz.) [online]. 2010, vol.67, n.2, pp. 223-227. ISSN 0103-9016.  http://dx.doi.org/10.1590/S0103-90162010000200015.

The traditional onion (Allium cepa) hybrid production requires the development of maintainer and male sterile lines and also a pollinator line with good specific combination ability. We report the identification of maintainer and male-sterile onion lines within the Brazilian 'Baia Periforme' derived population, 'Alfa São Francisco', associating random field pairing of male-fertile plants with selected male-sterile plants and PCR-based marker system monitoring S, T and N-cytoplasms. Male-sterile plants produced flowers with light green anthers which were easily detected in the field. A frequency of 2.0% of male-sterile plants was estimated in the 'Alfa São Francisco' sampled population. Male-sterile plants produced the 5'cob-marker 180-bp and the orfA501-marker 473-bp fragments, suggesting the T-cytoplasm type, while the maintainer line produced only the 5'cob-marker 180-bp. These identified lines will be important to develop tropical onion hybrids well-adapted to Brazilian low latitudes and to future comparative studies with other onion cytoplasmic genic male sterility systems.

Keywords : Allium cepa; CMS; 'Alfa São Francisco'; tropical hybrid.