Identification of varieties and testing of hybrid purity of rice by ultrathin-layer isoelectric focusing of seed protein

Abstract

Variety characterization and purity are among the most important requirements of a rice seed lot for sale. Therefore, variety identification, especially through examination of seeds, becomes increasingly important in terms of seed quality control and protection of breeders’ rights. Ultrathin-layer isoelectric focusing (UTLIEF) of seed protein is considered a convenient, quick, cheap, and reliable laboratory method and has been included in the International Seed Testing Association rules for variety verification (ISTA 1999). The cost per kernel of maize purity testing is US$0.14, $0.49, and $1.87 when analyzed by UTLIEF, simplesequence repeat (SSR) DNA markers, and isozymes, respectively (LUFA Augustenberg, unpubl. data). So far, UTLIEF has not been used in variety testing of rice. The objective of this study was to identify 20 rice varieties (Fig. 1) collected by the Seed Testing and Applied Botany, State Institute for Agricultural Testing and Research, Augustenberg, Germany, from different countries by UTLIEF.