Fig. 5: Identification of ploidy level of cells in gonadal fragments of triploid HHL (a1–d3) and diploid hybrids (e1–f3) using whole-mount FISH with chromosome-specific SatCE1 marker.

In the diplotene oocyte of triploid HHL hybrid (a1–a3), two adjacent signals are visible, suggesting the presence of two homologous chromosomes. Pachytene oocytes with bivalents and univalents (b1–b3) have signals on bivalent (indicated by thick arrow) as well as on univalent (indicated by arrowhead). Pachytene oocytes only with bivalents have one signal (indicated by an arrow) on bivalent (indicated by a thick arrow) (c1–c3). Diploid oogonia with two signals (indicated by arrows) and triploid oogonia with three signals (indicated by arrows) (d1–d3) are shown in the ovary from the triploid HHL hybrid. In the diplotene oocyte of diploid HL hybrid (e1–e3), two pairs of signals are visible, suggesting the presence of two bivalents. Diploid oogonia with two signals (indicated by arrows) and tetraploid oogonia with four signals (indicated by arrows) (f1–f3) in the ovary from diploid HL hybrid. DNA is stained by DAPI (cyan). Images (a1, b1, c1, d1, e1, and f1) are single confocal sections of 0.7 µm in thickness; corresponding 3D reconstructions (a2, b2, c2, d2, e2, and f2) and 3D surface reconstructions (a3, b3, c3, d3, e3, and f3) of metaphase plates with constructed isosurfaces of the signals and cells of interest. Scale bar = 10 µm.