Cereal cyst nematode (CCN; Heterodera avenae Woll.) is a root pathogen of cereals that can cause severe yield losses in intolerant wheat cultivars. Loci for resistance to CCN, measured by a seedling bioassay, were identified by creating a genetic map based on a Trident/Molineux doubled haploid population of 182 lines. A novel locus accounting for up to 14% of the resistance to CCN was mapped to chromosome 1B of Molineux by association with microsatellite marker loci Xwmc719 and Xgwm140. This locus acts additively with the previously identified CCN resistance loci identified on chromosomes 6B (Cre8) and 2A (Cre5 on the VPM1 segment) in this population to explain 44% of the genetic variance for this major wheat pathogen.

The cuticle is a layer covering the epidermis of the exposed parts of plants (e.g. stems, leaves). In spite of very wide occurrence, the chemical composition of plant cuticular layer is practically unknown (cf. Zetsche, 1932). Lee (1925) found that the cuticles of chrysanthemum and rose petals and the petioles of rhubarb leaves consisted of fatty acids, both free and esterified, soaps of fatty acids and some free higher alcohols, resinous substances and tannins. Triterpenoids, such as ursolic acid, were also reported in the cuticular layer of some 300 Japanese plants (Kariyine & Hashimoto, 1953; cf. Huelin & Gallop, 1951). On extraction of the

Abiotic and biotic stresses, such as mineral nutrition deficiency (especially nitrogen) and Fusarium attack, pose a global threat with devastating impact on wheat yield and quality losses worldwide. This preliminary study aimed to determine the effect of Fusarium inoculation and two different nitrogen levels on oxidative status and antioxidative response in nine wheat varieties. Level of lipid peroxidation, activities of antioxidant enzymes (catalase, ascorbate peroxidase, glutathione reductase), phenolics, and chloroplast pigments content were measured. In general, wheat variety, nitrogen, and Fusarium treatment had an impact on all tested parameters. The most significant effect had a low nitrogen level itself, which mostly decreased activities of all antioxidant enzymes and reduced the chloroplast pigment content. At low nitrogen level, Fusarium treatment increased activities of some antioxidative enzymes, while in a condition of high nitrogen levels, antioxidative enzyme activities were mostly decreased due to Fusarium treatment. The obtained results provided a better understanding on wheat defense mechanisms against F. culmorum, under different nitrogen treatments and can serve as an additional tool in assessing wheat tolerance to various environmental stress conditions.

B. (2022). Identification of a UDP -glucosyltransferase conferring deoxynivalenol resistance in Aegilops tauschii and wheat. Plant Biotechnology Journal. Portico.