MEDIA FOR THE INOVULO CULTURE OF PROEMBRYOS OF WHEAT AND WHEAT-DERIVED INTERSPECIFIC HYBRIDS OR HAPLOIDS

Rescue of very small proembryos of wheat, wheat haploids from wheat x alien crosses, or interspecific hybrids was possible without the support of any chlorophyllian tissue, through an intermediate step of ovule culture on rather complex media. This method allowed the recue of proembryos 1-6 days after pollination, For some wheat x alien hybrids and wheat itself, endosperm growth was occasionally observed on the U2.5 medium. Growth of endosperm was accompanied by improved morphogenesis. In wheat x maize crosses, the rate of wheat haploid plant regeneration was improved by a 2,4-D treatment of florets 24 h after pollination. One wheat x maize plant regenerated contained a maize chromosome in the root meristems, but the maize chromosome or DNA were not found in the colchicine-doubled progeny.