Background: Cleistogamic flowers are a main barrier in pollen dispersal for cross-pollination necessary in wheat
hybrid breeding. The aim of our study was to gain new knowledge on the biology of wheat flowering, in particular
on the differences between the cleisto- and chasmogamic forms which has certainly cognitive significance, but it
can also be used in practice when seeking a female and male ideotypes for cross hybridization.
Results: We characterized the most significant features defining the flowering specificity in two wheat cultivars
with contrasting tendency to cleistogamy: Piko (chasmogamous) and Dacanto (cleistogamous). In the field
observations we assessed diurnal pattern of anther extrusion and anther extrusion capacity. For the first time we
adapted the time lapse method for measuring kinetics of the spikelet movement and 3-D image correlation
technique for the non-invasive measurements of potential deformations of the spikelet lemmas. We found that the
two cultivars differ in the potential of pollen dispersion for-cross-pollination and in the spikelet kinetics. We also
described some anatomical traits that can have potential functional role in floret opening. None of the cultivars
showed any symptoms of lemma surface deformation.
Conclusions: The cleistogamic and chasmogamic wheat cultivars differ significantly in the potential for pollen
dispersion for cross-pollination, which is mainly related to anther extrusion capacity. Although none of these
features differentiated the cultivars clearly, we assume, based on spikelet kinetics and the lack of lemmas surface
deformation, that the water transport and turgor of cells is essential for the floret opening and anther extrusion in
wheat. The search for parental ideotype should be supported by marker assisted selection, e.g. based of polymorphisms
in genes related to aquaporin biosynthesis.