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Wheat leaf rust, caused by fungal pathogen Puccinia triticina Erikss, annually contributes to production losses as high as 40% in susceptible varieties and remains as one of the most damaging diseases of wheat worldwide. Currently, one of the major challenges of wheat geneticists and breeders is to accumulate major genes for durability of rust resistance called “slow rusting” genes using marker-assisted selection (MAS). Until now, eight genes (Lr34/Yr18, Lr46/Yr29, Lr67/Yr46, Lr68, Lr74, Lr75, Lr77, and Lr78) conferring resistance against multiple fungal pathogens have been identified in wheat gene pool and the molecular markers were developed for them. In MAS practice, it is a common problem that cultivars exhibiting desirable marker genotypes may not necessarily have the targeted genes or alleles and vice versa, which is known as “false positives.” The aim of this study was to compare the available four markers: Xwmc44, Xgwm259, Xbarc80, and csLV46G22 markers (not published yet), for the identification of the Lr46/Yr29 loci in 73 genotypes of wheat, which were reported as sources of various “slow rusting” genes, including 60 with confirmed Lr46/Yr29 gene, reported in the literature. This research revealed that csLV46G22 together with Xwmc44 is most suitable for the identification of resistance allele of the Lr46/Yr29 gene; however, there is a need to clone the Lr46/Yr29 loci to identify and verify the allelic variation of the gene and the function.

Leaf rust caused by the fungus Puccinia recondita f. sp. tritici is one of the most dangerous diseases of common wheat. Infections caused by fungal pathogens reduce the quantity and quality of yields of many cereal species. The most effective method to limit plant infection is to use cultivars that show rust resistance. Genetically conditioned horizontal-type resistance (racial-nonspecific) is a desirable trait because it is characterized by more stable expression compared to major (R) genes that induce racially specific resistance, often overcome by pathogens. Horizontal resistance is conditioned by the presence of slow rust genes, which include genes Lr34 and Lr46. This study aimed to identify markers linked to both genes in 64 common wheat lines and to develop multiplex PCR reaction conditions that were applied to identify both genes simultaneously. The degree of infestation of the analyzed lines was also assessed in field conditions during the growing season of 2017 and 2018. Simple sequence repeat anchored-polymerase chain reaction (SSR-PCR) marker csLV was identified during analysis in line PHR 4947. The presence of a specific sequence has also been confirmed in multiplex PCR analyses. In addition to gene Lr34, gene Lr46 was identified in this genotype. Lines PHR 4947 and PHR 4819 were characterized by the highest leaf rust resistance in field conditions. During STS-PCR analyses, the marker wmc44 of gene Lr46 was identified in most of the analyzed lines. This marker was not present in the following genotypes: PHR 4670, PHR 4800, PHR 4859, PHR 4907, PHR 4922, PHR 4949, PHR 4957, PHR 4995, and PHR 4997. The presence of a specific sequence has also been confirmed in multiplex PCR analyses. Genotypes carrying the markers of the analyzed gene showed good resistance to leaf rust in field conditions in both 2017 and 2018. Research has demonstrated that marker assisted selection (MAS) and multiplex PCR techniques are excellent tools for selecting genotypes resistant to leaf rust.

The article presents the technological and antioxidant properties of potato juice (PJ) protein concentrate obtained by the novel ultrafiltration method. Commercial products, obtained from waste PJ by the traditional method of acid coagulation of proteins, were studied for comparison. Functional properties such as water or oil absorption, foaming capacity, and foam stability (FS) as well as solubility at various pH were assessed. Moreover, the total phenolic compound content, antioxidant activity, and mineral composition were determined. The results showed that PJ protein concentrate obtained by ultrafiltration has good oil absorption properties (6.30 mL/g), which is more than two times higher than the commercial proteins used in the comparison (P2 = 2.33 mL/g and P3 = 2.67 mL/g). Moreover, the ability to create and stabilize foam was also higher (FS ranging from 20.0% at pH = 10 to 11.3% at pH = 2 after 60 min of testing). It had higher content of macro- and microelements and antioxidant activity compared to other samples. Therefore, it is possible to obtain interesting potato protein concentrate from the waste product of the starch production process, which may be an interesting raw material for enriching food.

A number of studies have shown that the greater the genetic diversity of parental lines, the greater the heterosis effect. Genetic or phenotypic variation can be estimated by genotype testing on the basis of the observations obtained through prediction (a priori) or the observations and studies (a posteriori). The first method uses data such as the genealogy of a given subject and the information about its geographical origin. The second method is based on the phenotypic observation and studies, as well as on the molecular research. The development of molecular genetics and genotype testing methods at the DNA level has made it possible to rapidly assess the genetic variability regardless of the modifying effect of the environment. The aim of this study was to determine the relationship between the degree of relatedness and the DNA polymorphism (determined using AFLP, RAPD, and SSR markers) of inbred maize lines and the effect of hybrid-form heterosis. Our analysis demonstrated that the parental components for heterosis crosses can be selected on the basis of the genetic similarity determined using the molecular SSR markers and the Jaccard, Kluczyński, Nei, and Rogers coefficients. Molecular AFLP markers proved less useful for selecting the parental components, but may be used to group lines with incomplete origin data. In the case of the RAPD markers, no clear relationship between genetic distance and the heterosis effect was found in this study.

The main challenge of agriculture in the 21st century is the continuous increase in food production. In addition to ensuring food security, the goal of modern agriculture is the continued development and production of plant-derived biomaterials. Conventional plant breeding methods do not allow breeders to achieve satisfactory results in obtaining new varieties in a short time. Currently, advanced molecular biology tools play a significant role worldwide, markedly contributing to biological progress. The aim of this study was to identify new markers linked to candidate genes determining grain yield. Next-generation sequencing, gene association, and physical mapping were used to identify markers. An additional goal was to also optimize diagnostic procedures to identify molecular markers on reference materials. As a result of the conducted research, 19 SNP markers significantly associated with yield structure traits in maize were identified. Five of these markers (28629, 28625, 28640, 28649, and 29294) are located within genes that can be considered candidate genes associated with yield traits. For two markers (28639 and 29294), different amplification products were obtained on the electrophorograms. For marker 28629, a specific product of 189 bp was observed for genotypes 1, 4, and 10. For marker 29294, a specific product of 189 bp was observed for genotypes 1 and 10. Both markers can be used for the preliminary selection of well-yielding genotypes. [ABSTRACT FROM AUTHOR]

Ten leading wheat cultivars originating from the Plant Breeding and Acclimatization Institute (IHAR) - National Research Institute (Poland) and the Department of Gene Bank (Czech Republic) were used to establish a field experiment in 2017 and 2018 at the Dłoń Experimental Farm. The analyzed wheat genotypes were characterized by diversified field resistance to leaf rust. Jubilatka, Thatcher and Sparta were the most resistant cultivars in field conditions in both 2017 and 2018. The aim of the work was to identify the Lr11, L13, Lr16 and Lr26 genes encoding resistance to leaf rust using molecular SSR markers (wmc24, wmc261, Xgwm630, Xwmc764 and P6M12) and to develop multiplex PCR conditions to accelerate identification of these genes. Markers of three leaf rust resistance genes have been identified simultaneously in these cultivars. Jubilatka, Thatcher and Sparta cultivars may serve as a good source of the analyzed leaf rust resistance genes. In addition, multiplex PCR conditions have been developed for the simultaneous identification of the Lr11 and Lr16 and Lr11 and Lr26 gene pairs.

The aim of the study was to identify the Pm2, Pm3a, Pm4b and Pm6 genes and to develop multiplex PCR reaction conditions to reduce time and limit analysis costs. The following molecular markers were used for gene identification: Xcfd81, Whs350 and Xgwm205 (for Pm2), Pm3a (for Pm3a), STS_241 and Xgwm382 (for Pm4b), NAU/BCDSTS 135-2 (for Pm6). Plant material consisted of 7 popular European wheat varieties from the wheat collection at the Department of Genetics and Plant Breeding of the Poznań University of Life Sciences. The field experiment was established in 2017 and 2018 on 10 m2 plots in a randomized complete block design in three replicates in the Dłoń Agricultural Experimental Farm of the Poznań University of Life Sciences (51°41’23.835”N 017°4’1.414”E). The analyses demonstrated that the accumulation of all identified Pm genes was found in the Assosan variety. The accumulation of the Pm2, Pm4b and Pm6 genes was found in Atomic, Bussard, Lear, Sparta, Tonacja and Ulka varieties. The work also involved developing multiplex PCR conditions for Xcfd81 and STS_241 and Xcfd81 and Xgwm382 primer pairs, allowing the simultaneous identification of the Pm2 and Pm4b genes.

The main efforts in common wheat (Triticum aestivum L.) breeding focus on yield, grain quality, and resistance to biotic and abiotic stresses. One of the major threats affecting global wheat cultivation and causing significant crop production losses are rust diseases, including leaf rust caused by a biotrophic fungus Puccinia triticina Eriks. Genetically determined resistance to leaf rust has been characterized in young plants (seedling resistance) as well as in plants at the adult plant stage. At the seedling stage, resistance is controlled vertically by major R genes, conferring a race-specific response that is highly effective but usually short-lived due to the rapid evolution of potentially virulent fungi. In mature plants, horizontal adult plant resistance (APR) was described, which provides long-term protection against multiple races of pathogens. A better understanding of molecular mechanisms underlying the function of APR genes would enable the development of new strategies for resistance breeding in wheat. Therefore, in the present study we focused on early transcriptomic responses of two major wheat APR genes, Lr34 and Lr67, and three complementary miRNAs, tae-miR9653b, tae-miR9773 and tae-miR9677b, to inoculation with P. triticina. Plant material consisted of five wheat reference varieties, Artigas, NP846, Glenlea, Lerma Rojo and TX89D6435, containing the Lr34/Yr18 and Lr67/Yr46 resistance genes. Biotic stress was induced by inoculation with fungal spores under controlled conditions in a phytotron. Plant material consisted of leaf tissue sampled before inoculation as well as 6, 12, 24 and 48 h postinoculation (hpi). The APR gene expression was quantified using real-time PCR with two reference genes, whereas miRNA was quantified using droplet digital PCR. This paper describes the resistance response of APR genes to inoculation with races of leaf rust-causing fungi that occur in central Europe. The study revealed high variability of expression profiles between varieties and time-points, with the prevalence of downregulation for APR genes and upregulation for miRNAs during the development of an early defense response. Nevertheless, despite the downregulation initially observed, the expression of Lr34 and Lr67 genes in studied cultivars was significantly higher than in a control line carrying wild (susceptible) alleles. [ABSTRACT FROM AUTHOR]

Currently, production of wheat cultivars (Triticum aestivum L.) that show durable field resistance against fungal pathogens is a priority of many breeding programs. This type of resistance involves race-nonspecific mechanisms and can be identified at adult-plant stages. Until now, seven genes (Lr34/Yr18, Lr46/Yr29, Lr67/Yr46, Lr68, Lr75, Lr77 and Lr78) conferring durable types of resistance against multiple fungal pathogens have been identified in the wheat gene pool. In this study we showed a multiplex Polymerase Chain Reaction (multiplex PCR) assay, which was developed for detection of slow rusting resistance genes Lr34, Lr46, Lr68, using molecular markers: csLV34, Xwmc44 and csGS, respectively. Identification of molecular markers was performed on 40 selected wheat genotypes which are the sources of slow rusting genes according to literature reports. Multiplex PCR is an important tool to reduce the time and cost of analysis. This multiplex PCR protocol can be applicable for genotyping processes and marker assisted resistance breeding of wheat. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]