Hybridity Test of Cucumbers via Ultrathin Layer Isoelectric Focusing Technique Using Water as the Extraction Buffer

Abstract

The ultrathin layer isoelectric focusing (UTLIEF) technique using water as the extraction buffer is a cheap, fast and reliable technique for varietal identification in cucumber. However, its application for hybridity testing has not been reported yet. Therefore, this study evaluated the possibility of the application of the UTLIEF technique for testing the hybridity of 10 F1 hybrid seeds and their respective parental lines. It was found that nine out of the ten pairs of the parental lines could be differentiated by the differences in the combination of male and female marker bands, while eight out of the ten F1 hybrid seed were verified using only male marker bands using this UTLIEF technique with water as the protein extract solvent and a gel pH range of 2–11. More male marker bands were found than female marker bands. Most of the polymorphic cucumber seed protein bands were focused in the pH range 6–10. The results indicated that the UTLIEF technique using water as the extraction buffer and a gel pH gradient of 2–11 is of value for hybridity testing in commercial cucumber hybrid seed production.