Production of Embryos from Microspore Cultures of Portuguese Tronchuda Cabbage Landraces

Twelve accessions of tronchuda cabbage landraces were tested for their ability to produce embryos through microspore culture in NLN-13 medium. A sample from all the isolations was stained with DAPI for determination of microspore developmental stage. The relationship between the microspore developmental stage and the production of microspore-derived embryos was evaluated. Embryos were obtained from all the accessions. Considerable variation was observed between isolations with different developmental stage of microspores, accessions and plants within the same accession. The best embryogenic responses occurred in microspore populations with approximately 10 to 89% of binucleate pollen. The highest embryo yield was obtained with one of the ‘Couve de Valhascos’ accessions (0.41 embryos / 1 000 microspores) and the lowest yields with the accessions of ‘Couve Portuguesa’ (less than 0.07 embryos / 1 000 microspores).