Factors affecting the regeneration capacity of isolated barley microspores (Hordeum vulgare L.).

The culture of isolated microspores of barley (Hordeum vulgare L. cv. Kymppi, an elite malting barley cultivar) was studied. A careful choice of culture steps resulted in an average regeneration frequency of 300 green plants per starting material spike. Strong seasonal variation in regeneration capacity was observed. The choice of a cold pretreatment method affected the viability of microspores. A cold pretreatment of the collected starting material at +4°C for 4 weeks was needed for the efficient regeneration of green plants from isolated microspore cultures. Glutamine omission from and copper additions to microspore culture were studied. The omission of glutamine did not affect the number of regenerated green plants but did result in an increase in the number of regenerated albino plants. The addition of copper did not improve the regeneration capacity of isolated barley microspores. Transformation by particle bombardment of isolated microspores did not result in the production of transgenic plants.