Plant regeneration of isogenic lines of the Maringá genotype of wheat (Triticum aestivum L.) with short height genes (Rh1 and Rht2)

摘要

Different genotypes show different responses for in vitro plant regeneration. In previous work with lhe Maringá genotype a result of 100% of in vitro plant regeneration was obtained. The purpose of this study was to investigate the capacity of plant regeneration of Maringá genotype and two of it's isogenic lines with one and two shorts heigth genes (Rht1 and Rht2). Imature embryos from: (a) Maringá, (b) the isogenic lines and (c) the crosses between these genotypes were placed on MS medium (modified by MILACH et al., 1991) with saccharose, agar and decreasing doses of 2,4D (2mg/l; 0.5mg/l; 0.1mg/l and 0.0mg/l) according to the stage of culture. The possibility of suppressing one of the stages of culture, (which uses 0.1mg/1 of 2.4D) was also evaluated. The statistic analisys demonstrated that the different genotypes gave different responses, therefore this indicates that the Rht genes had influence on plant regeneration rates. The suppression of the stage of culture which uses 0.1mg/l of 2,4D did not have any influence on regeneration, showing that this stage can be eliminated. Different genotypes had the same responses on the different culture medium sequences. The intercection between genotype x medium was not significam.