Autotoxicity in isolated microspore cultures of <i>Brassica napus</i>

Abstract

Effects of a suspected toxin in isolated microspore cultures of oilseed rape, Brassica napus L., were observed in the reduced levels of embryogenesis and in altered embryo morphology. The toxin appeared to be generated by the cultured spores themselves. Inclusion of binucleate microspores in the cultures, along with younger, potentially embryogenic spores, was correlated with these negative effects and could be simulated by inoculation of embryogenic cultures with media generated from high-density cultures of older spores. Replacement of culture media 24 h after microspore isolation effectively reduced the levels of the autotoxins in the medium and allowed normal embryo development.