Pollen Tube Growth in Incompatible Pistils and Style-grafted Pistils of ‘Satonishiki’ Sweet Cherry

Prunus fruit trees of the Rosaceae family exhibit S-RNase-based gametophytic self-incompatibility (GSI), which enables pistils to reject self-pollen by suppressing pollen tube elongation. In other plant species with GSI, it has been shown that this suppression consists two steps: first, slowing down elongation in middle part style and second, complete arrest involving programmed cell death. To characterize pattern incompatible tubes Prunus, we observed ‘Satonishiki’ sweet cherry (Prunus avium) ‘Rainier’ on agar plates growth cut branches. Incompatible selfed delayed penetration into stigma both experiments. Observation was difficult 24 h after pollination (HAP) due wilting styles, while observing them branches possible up 72 HAP. branches, barely elongated self from 32 48 HAP when compatible reached base a style, but resumed style. An RNase activity staining indicated S-RNase inactive Finally, style-grafted accelerated upper one-third self-pollinated styles grafted onto ‘Taishonishiki’ pistils. These results P. avium consistently reversible. We discuss mechanism possibility artificial control self-incompatibility.