IN-VITRO POLLEN MATURATION AND FERTILIZAT ION IN DETACHED SPIKELET CULTURES OF WHEAT

In the recent years, the in vitro culture of plant reproductive organs has been raising increased interest beside the anther culture techniq ues. The method will hopefully enable us to manipulate the sexual proc esses and seed development under controlled circumstances in the near future. The present report describes the gametogenesis and seed settin g of three different wheat genotypes on solid medium spikelet culture. In artificial conditions the sexual processes proved to be similar to the normal flowering, but the seed set decreased considerably while t he in vitro fertility of the different genotypes showed significant di fferences The cytological analysis of the in vitro ripened pollen popu lation revealed significant decrease in viability and pollen quality a s well depending on the genotype. At the same time each genotype produ ced sufficient number of functionable pollen grains for the successful fertilisation therefore the low seed set can at least partly attribut ed to the disfunction of the female reproductive organ. The in vitro d eveloped seeds had normal morphology although they showed considerable shrinking after drying because of their incomplete endosperms. Inspit e of that most of them germinated in laboratory conditions.