Tracing pollen nuclei in the ovary and ovule of Gasteria verrucosa (Mill.) H. Duval after pollination with DAPI-stained pollen

Summary The addition of DAPI particles to the stigma exudate of Gasteria results in the labelling of the pollen nuclei. By means of epifluorescence microscopy and clearing of the ovule, the labelled nuclei of the sperm cells and, subsequently, the zygotic nucleus can be observed. The method was used in a cross-pollination with low seed setting to examine different types of penetration and transport of the pollen tube nucleus and sperm cell nuclei. More than one pollen tube can penetrate, but generally only one set of sperm cell nuclei is accepted.