The effect of ovary-conditioned medium on microspore embryogenesis in common wheat (Triticum aestivum L.)

Microspores were isolated from wheat (Triticum aestivum L.) spikes of various genotypes following an effective pretreatment that induced microspore embryogenesis. The isolated microspores were cultured with or without live ovaries, and with or without medium pre-conditioned by ovaries. for varying periods of time. Live ovaries alone increased androgenic embryoid yields up to 4.5-fold over the control for microspores isolated from responsive genotypes. While live ovary co-culture alone was not effective for microspores isolated from recalcitrant genotypes, the addition of medium preconditioned by ovaries to microspore, cultures increased embryoid yield by more than 100-fold. Without ovary-conditioned medium, no embryoids could be obtained from some recalcitrant genotypes. Ovary-conditioned medium apparently functions to increase embryoid yields by providing essential substance(s) for elaboration of the embryogenic program already triggered during pretreatment.