Partial success of marker-assisted selection of 'A' and 'B' onion lines in Brazilian germplasm

This work aims to identify 'A' and 'B' onion lines in Brazilian germplasm, associating marker-assisted selection (MAS) of cytoplasm type and the Ms locus with pollen viability analysis. MAS and pollen viability tests presented a complete agreement for the lines Alfa SF, BRS 367, BRS 367, Cascuda T7, Cascuda T5, EHCEB 20102017 and EHCEB 20142027. MAS was not validated by the pollen viability tests in some plants of the lines Alfa SF, EHCEB 20142028, EHCEB 20141028, EHCEB 20141027 e EHCEB 20141017. Plants with fertile pollen within a specific 'A' line were eliminated before anthesis. The methods used to evaluate pollen viability did not present agreement in the sterile and fertile classification in five onion accessions. Six pairs of 'A' and 'B' lines identified in the present study [Alfa SF (Tmsms) x Alfa SF (Nmsms), BRS 367 (Tmsms) x BRS 367 (Nmsms), Cascuda T7 (Nmsms) x Cascuda T5 (Smsms), EHCEB 20142027 (Nmsms) x 20141027 (Tmsms), EHCEB 20102017 (Nmsms) x EHCEB 20141017 (Tmsms), and EHCEB 20142028 (Nmsms) x EHCEB 20141028 (Smsms)] have potential for onion hybrid development.