Knowledge of genetic diversity in breeding material is fundamental for hybrid selection programs and for germplasm preservation as well. Research has been done with nine irradiated (fast neutron) and four non-treated inbred lines. The aims of this study were (1) to investigate the degree of genetic variability detected with morphological descri...ption (based on CPVO TP/2/2) in these materials, (2) to compare the genetic changes among irradiated and non-irradiated maize inbred lines (based on some quantitative features). The irradiation did not change any of the characteristics clearly in positive or negative way, which can be related to the fact that the effect of induced mutation on genetic structure cannot be controlled. From the irradiated lines we have managed to select plants with earlier ripening times and better phenotypes. We could distinguish 3 main groups by the morphological features; these results match our expectations based on pedigree data. Markers distinguishable on the phenotypic level (e.g. antocyanin colouration, length of tassels) were significant in all lines.
Heterosis breeding in maize caused gene erosion by using uniform inbred lines. In order to strengthen the genetic base, we established a gene bank containing lines with broad genetic variability, resistance and adaptability. The maize gene bank is a result of our work in the past two decades.
The gene bank originated from treatments of maize
The traditional Hungarian horse breed, Gidran has been close to the edge of extinction several times. Despite the multiple bottleneck effect, the breed has retained a part of its genetic variability, and performed prominently in carriage driving and show-jumping competitions. Maintaining of the Gidran breed is important in the point of view of...world heritage; because besides Hungary, smaller Gidran populations exist only in Bulgaria and Romania. Taking advantage of the special inheritance features of mtDNA, our study focused on two mtDNA regions of Gidran mares. Altogether, 251 hair samples from various Hungarian studs were examined. The analysis was successfully made in case of 251 samples of the cytochrome b and in case of 246 samples of D-loop regions. Because of the distinct mutation rates of the two mtDNA markers, the number of the haplotypes and the way of grouping samples into haplotypes was different. Our key finding was that most haplotypes may be compatible with mare families of the stud book; however incidental mistakes in stud book have occurred only in a few cases. Our results indicate the importance of the preservation and breeding those mare families, which are molecular genetically more diverse than the others, and are in the edge of extinction.