The identification of the onion cytoplasm was obtained by the development of DNA specific primers to "S", "T" and "N" types. The goal of this work was the identification of the cytoplasm type in two different onion populations in the São Francisco river Valley, in order to facilitate the development of onion hybrids from Northeast Brazil. In the sample of 19 plants of the BRS Alfa São Francisco cultivar was observed the amplification of fragments of 180 bp and absence of the fragment of 414 bp of the 5'cob primers and the presence of fragment of 473 bp of the orfA501 primers, indicating that the cytoplasm of the population is the "T". Plants with cytoplasm N were also identified in the BRS Alfa São Francisco population. The amplification of consistent fragments with the 180 and 414 bp of 5'cob primers was observed in the sample of 44 plants of a Valenciana type population and, the presence of a fragment of 473 bp of orfA501 primers, indicating that the cytoplasm of the population is the "S". No plant with cytoplasm N was identified in the Valenciana population. The development of a tropical onion hybrid is possible, based on the BRS Alfa São Francisco cultivar, while in the Valenciana type, the introgression of N cytoplasm will be necessary.
Allium cepa; male-sterility; PCR; hybrids
