An ink for a display panel effective in reducing the uneven adhesion of the ink is applied by an ink application apparatus using an inkjet method to form a structural layer of a display panel such as a plasma display panel. The pulse width adjustment portion outputs an adjusted pulse width data which corresponds to the pulse width indication signal when the pulse width indicated by the pulse width indication signal is equal to or wider than a predetermined width. Also provided by the invention are tissue cultures of the soybean variety A1035302 and the plants regenerated therefrom. The opening has a diameter greater than a diameter of the well.