| Summary: | Cytological and ultrastructural features of wheat microspores before and after starvation as well as during the first days of in vitro initiation of embryogenesis are described. It is shown that the microspores subjected to stress starvation at 33°C are characterized by the fragmentation of the vacuole, and the formation of cytoplasmic strands that pass through the vacuole and connected a nucleus-containning cytoplasmic pocket with the subcortical cytoplasm. Sporo-phytic development is started when starved pollen are transfered to non-stress condition, in which 25% of the population of viable embryogenic pollen divided symetrically within 48 hours. Another visible sign of this pathway is mediated by deviation of intine development and proliferation of all cytoplasmic contains.
Keywords : microspore, embryogenesis, stress, ultrastructure, Triticum aestivum L.
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