Solid-stemmed spring wheat cultivars (Triticum aestivum L.) are resistant to the stem sawfly (Cephus cinctus Nort.) and lodging. Anthers of 24 spring wheat cultivars with varying content of pith in the stem were used in the experiment. All were classified into three groups: solid, medium–solid and hollow stems. There was considerable influence of the cultivar on callus formation and green plant regeneration. The highest efficiency of green plant regeneration (24%) was observed for the solid-stemmed AC Abbey cultivar. There was no regeneration from the explants of four cultivars: CLTR 7027, Alentejano, Marquis and Bombona. Principal component analysis showed no differences between the cases under observation (callus induction and green plant regeneration) in their response to pre-treatment temperatures (4 and 8°C). The examination of the effects of various auxin types in the induction medium on callus formation and green plant regeneration revealed that the strongest stimulation of these processes was observed in the C17 medium with 2,4-D and dicamba. The efficiency of callus formation and green plant regeneration was greater in solid-stemmed cultivars than in hollow-stemmed cultivars.

Androgenesis is potentially the most effective technique for doubled haploid production of wheat. It is not however widely used in breeding programmes due to its main limitation: the genotype dependence. Due to genetic differences between spring and winter wheat, it was assumed that both phenotypes are different in their capacity to conduct androgenesis. And so, the aim of this investigation was to verify the effectiveness of androgenesis induction and plant regeneration of spring and winter wheat genotypes while considering varying amounts of growth hormones in the induction medium. Fifteen genotypes of spring wheat and fifteen of winter wheat were used in the experiment. Six hundred anthers of each of the 30 genotypes were plated and analysed. Previous studies have allowed selection of the best medium for wheat androgenesis and a combination of growth hormones that are the most effective in stimulating microspore proliferation. Therefore, C17 induction media with two combinations of growth hormones were used: I—supplemented only by auxins (2,4-D and dicamba), and II—supplemented by auxin and cytokinin (2,4-D and kinetin). Data was recorded according to the efficiency of androgenic structure formation (ASF), green plant regeneration (GPR), and albino plant regeneration (APR). The results showed that the induction and regeneration of androgenesis in the spring wheat were more efficient than in the winter ones. The spring genotypes formed more androgenic structures and green plants on anthers plated on the medium supplemented only by auxins, in contrast to the winter genotypes which were better induced and regenerated on the medium supplemented by auxin and cytokinin. The study showed that to increase the efficiency of androgenesis, it is necessary to select appropriate factors such as concentration and type of hormones in medium composition, affecting the course of the culturing procedure according to the winter or spring phenotype of donor plants.

Leaf rust pathogens are able to overcome plants' resistance by the appearance of new races. Therefore, an introduction of leaf rust resistance genes into highyielding wheat genotypes is essential. One of such genes is Lr19 (leaf rust resistance gene) that could be a source of resistance in polish breeding programs. The aim of this study was to obtain doubled haploid lines of the Lr19 gene in anther cultures of winter wheat genotypes. In the experiment, F 3 generation plants from two cross-combinations were used: genotype T39 × Ozon and genotype T36 × Hondia (T36 and T39 lines carry Lr19 gene). Three combinations of growth regulators such as 2,4-D; 2,4-D and dicamba; and 2,4-D and kinetin were applied. A total of 13,550 anthers were tested. The embryo-like structures were formed at an average frequency of 9.95% and were mainly influenced by the genotype, not by the composition of hormones in induction media. Regeneration frequency of green plants was recorded to be 1.45%. The highest frequency of green plant regeneration was observed on induction media supplemented with 2,4-D and dicamba reaching 1.79%. Spontaneous doubled haploids tested by laser flow cytometry were detected in 33.95% of plants. The frequency of the formation of embryo-like structure was mainly influenced by the genotype, not by the composition of hormones in induction media.

Among all cereals, common wheat (Triticum aestivum L.) occupies the largest area of crops worldwide. Wheat leaf rust, caused by the pathogen Puccinia recondita f. sp. tritici considerably reduces the yield of wheat. Breeding for resistance combined with selection based on molecular markers may become an effective tool in the struggle against fungal diseases. Lr19 is the gene that carries high resistance to wheat leaf rust. In recent years, we have seen the development of many molecular markers in close neighbourhood of the Lr19 gene, e.g., SCS265, SCS253, GB, Xwmc221, XustSSR2001-7DL, Xgwm37 and Xgwm44. The aim of the study was to investigate the functionality of molecular markers related to the Lr19 gene. The study was based on two reference genotypes with the Lr19 gene ('Agatha' and Lr19) and three lines strongly infested by wheat leaf rust. Seven molecular markers were analysed, but only two of them (GB and Xwmc221) proved to be specific to the gene under study. These markers were used for analysis of 25 wheat genotypes, which were evaluated for leaf rust resistance in field conditions to confirm their usefulness for selection of breeding material. These findings point to the need of continuous search for functional molecular markers giving repeatable and reliable results.

Evaluation of the usefulness of molecular markers Xgwm205, Xcfd81, Whs350 for the identification of resistance gene Pm2 to powdery mildew (Blumeria graminis f. sp. tritici) in wheat cultivars of different origins Ocena przydatności markerów molekularnych Xgwm205, Xcfd81, Whs350 do identyfikacji genu odporności Pm2 na mączniaka prawdziwego zbóż i traw (Blumeria graminis f. sp. tritici) u odmian pszenicy o zróżnicowanym pochodzeniu

Identification of brown rust resistance gene Lr19 caused by Puccinia recondita f. sp. tritici in foreign cultivars of winter wheat Triticum aestivum L. Identyfikacja genu Lr19 warunkującego odporność na rdzę brunatną powodowaną przez Puccinia recondita f. sp. tritici w zagranicznych odmianach pszenicy ozimej Triticum aestivum L.