The safety of wheat production in Hungary requires the propagation of droughttolerant cultivars because of the regular occurrence of water deficiency. Hybridization between related species makes it possible to transfer desirable traits from one species to another. Introgression lines developed from wheat/barley hybrids were investigated together with the parental wheat and barley cultivars to determine how the added barley chromosome (segment) influences drought tolerance in wheat. The plants were grown in the field at the UP Georgikon Faculty, Keszthely. Sowing and harvest were done by hand. Half the length of the 12 m rows was covered with a plastic rain shelter on 2
April (EC: 30–31) to protect the plants from rain, resulting in a 163 mm difference in water supplies between the control (not covered) and stressed (covered) treatments. Data were obtained for anthesis and maturity date, plant height, root/shoot ratio, leaf water potential, grain yield and grain yield components. The plants adapted to water deficiency by increasing the root/shoot ratio and decreasing the water potential and the duration of grain filling. The grain yield was reduced by 12%, averaged over the genotypes, mainly due to a decrease in the number of spikes per plant.
New wheat × barley, wheat × Aegilops biuncialis and wheat × rye hybrids were produced with the aim of alien gene transfer from these species into wheat. Amphiploids were produced with the help of colchicine treatment from the last two combinations. The new wheat × barley hybrids were multiplied in tissue culture because of the high degree of sterility and then pollinated with wheat to obtain backcross progenies. Wheat-barley chromosome pairing was detected using genomic in situ hybridization (GISH) in two combinations (Mv9 kr1 × Igri, Asakazekomugi × Manas). In vitro conditions caused an increase in chromosome arm association frequency in both combinations and in fertility in some regenerants. Five wheat-barley translocations were produced in a wheat background and characterized through the combination of cytogenetic and molecular genetic approaches (GISH, FISH and SSR markers). The following translocations were identified: 2DS.2DL-1HS, 3HS.3BL, 6BS.6BL-4HL, 4D-5HS and 7DL.7DS-5HS. Physical mapping of the SSR markers on chromosomes 1H and 5H was carried out using the intragenomic and interspecific translocation breakpoints and the centromere as physical landmarks. Disomic wheat-Aegilops biuncialis additions were produced after backcrossing the wheat-Ae. biuncialis amphiploids. Fluorescence in situ hybridization (FISH) was carried out using two repetitive DNA clones (pSc119.2 and pAs1) on Ae. biuncialis and its two diploid progenitor species to detect chromosome polymorphism. The 7M and 3M disomic chromosome additions were selected and five more lines still need to be characterized. The octoploid triticale (Mv9 kr1 × Lovászpatonai) produced in Martonvásár was crossed with a 1RS.1BL wheat cultivar Matador. GISH analysis detected pairing between the 1RS arm of the translocation chromosome and that of Lovászpatonai rye in 32 % of the pollen mother cells, making it possible to select recombinants from this combination. The new recombinants between the 1RS of Petkus and the 1RS of Lovászpatonai rye cultivars are being analysed with the help of microsatellite markers.