Genetic diversity was investigated in a set of eleven hexaploid wheat genotypes originated from CIMMYT, Turkey in comparison with some modern European mostly originated from KWS wheat breeding program using 24 wheat SNP markers. The lowest and highest genetic dissimilarities were observed between genotypes Opus and LDO 330/06, KWS Salix and LDO 330/06, respectively. Based on cluster analysis, 38 wheat genotypes were grouped in two main clusters. Although the grouping pattern is very origin heterogeneous in each group, the grouping pattern of some genotypes appeared to be associated, to some extent. Principal coordinate analysis (PCoA) was used as an alternative way of visualizing the genotypic data. The first, second and third principal components explained 17.79%, 14.39% and 12.24% of the variation, respectively. This study can also be an indicator for breeders to evolve genotypes with diverse genetic background to achieve sustainability in wheat production, to get favorable heterotic combinations in a wheat improvement program.
Authors:Tihana Marček, Marija Viljevac Vuletić, and Valentina Španić
In wheat, Fusarium fungus promotes the appearance of destructive disease named as Fusarium head blight (FHB) that can cause grain yield reduction and mycotoxin accumulation. The focus of this research was to verify the influence of Fusarium graminearum and F. culmorum on wheat genotypes with different susceptibility to FHB: “Super Žitarka” (susceptible), “Lucija” (moderately resistant) and “Apache” (resistant). The experiment was performed under field conditions by artificial spore inoculation of ears at the flowering stage. The effectiveness of antioxidative enzymes, hydrogen peroxide (H2O2) content and malondialdehyde (MDA) content were observed at several sampling points after Fusarium inoculation (3, 15 and 24 hours). “Lucija” responded to pathogen by increase of guaiacol peroxidase (POD) activity, high H2O2 and MDA content in the early post-inoculation times (3 and 15 hours), compared to control. “Super Žitarka” displayed inhibition of catalase (CAT) activity throughout the whole time course of the experiment. Infected plants of “Apache” showed notable decline in MDA content over time. Moreover, in “Apache” increased H2O2 accumulation was observed immediately after Fusarium exposure (3 and 15 hours), compared to 24 hours. Rapid overproduction of H2O2 under Fusarium stress marked “Apache” as FHB-resistant.