EFFICIENT MICROSPORE EMBRYOGENESIS IN WHEAT (TRITICUM-AESTIVUM L) INDUCED BY STARVATION AT HIGH-TEMPERATURE

We have established an efficient method to induce embryo formation fro m isolated wheat (Triticum aestivum L.) microspores. Culture of excise d anthers under starvation and heat shock conditions induced the forma tion of embryogenic microspores at high frequency in nine Austrian win ter wheat genotypes, including cultivars that had been considered as r ecalcitrant in anther culture. Percoll gradient centrifugation of the mechanically isolated microspores allowed us to obtain homogeneous pop ulations of embryogenic microspores in all genotypes which, after tran sfer to a rich medium containing immature ovaries for conditioning, di vided and produced globular embryos. Thousands of embryos were produce d in one petri dish. Many of these embryos developed into plantlets af ter transfer to a solid medium without ovaries.