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The designation of traditional varieties of grapevine is usually based on verbal information or very dated records. Old rare cultivars found in the Czech Republic were identified by Simple Sequence Repeat (SSR) analysis, a generally accepted method for cultivar identification. These cultivars are primarily maintained in a national collection of genetic resources. Finally a total of 102 candidate genotypes was selected where 49 traditional varieties were identified on the base of nine SSR loci compared with the European Vitis Database. Thirty-six items were registered under the correct designation. The remaining genotypes included four clones, and two genotypes could be described as synonyms. Seven genotypes were found to be incorrectly marked. For three of them, the correct name was found in the database under their SSR profile and four items were considered to be unique as no identical profile was found.

In 2016-2018 virulence of the Czech wheat leaf rust population was studied on Thatcher near-isogenic lines, carrying different Lr genes, and 130 leaf rust isolates. Virulence to Lr9 was found only sporadically. Virulence frequency to Lr2a, Lr2b, Lr2c and Lr28 was lower than in previous years. All tested isolates were avirulent to Lr19. Lr24 conditioned resistance to majority of isolates. Nineteen recently registered Czech cultivars were tested with six isolates of the pathogen and Lr genes were postulated. Presence of genes Lr1, Lr10, Lr19, Lr24, Lr26, Lr28, Lr34 and Lr37 was tested by molecular markers. Lr37 prevailed, followed by Lr genes 10, 24, 28, 1 and 26; genes Lr19 and Lr34 were not determined.

The study is aimed at evaluating the pod shattering resistance of F₈ soybean lines based on the shattering incidence and shattering severity. The materials consist of fourteen F₈ soybean lines and two check cultivars. The pod shattering incidence was examined by using the oven-dry method, meanwhile, the shattering severity was evaluated based on the severity of the pod opening. The pod shattering resistance based on the shattering incidence resulted in five resistant lines (7-10% shattering), seven moderate lines (13-23% shattering), one susceptible line (53% shattering), and one very susceptible line (100% shattering). The pod shattering resistance based on the shattering severity showed that the pod opening on the ventral side differed between the lines and between the shattering degree, and it tends to form sigmoid curves with a different peak position for each shattering degree. The shattering severity of the resistant, moderate, and susceptible lines reached a peak at 60 °C, 50 °C, and 40 °C, respectively. A longer pod length indicated by the length of the dorsal (r = 0.827**) and ventral (r = 0.880**) sides of the pod, a higher total pod weight (0.827**), and a larger seed size (0.794**) will increase the degree of susceptibility to pod shattering. Those characteristics were considered to be the ones that should be used as the selection criteria in the breeding programme for pod shattering resistance in soybeans.

To study the impact of parent-inbred lines on the heterosis expression of the agronomic characteristics in sunflower hybrids, 24 sunflower hybrids along with the parent lines were evaluated for their agronomic characteristics as a randomised complete block design with three replications in the 2018-2019 growing seasons in Karaj, Iran. According to the results, the hybrids R29 × A346, R19 × A346, R29 × A40 had the highest achene yield (4 159, 4 143 and 4 108 kg/ha, respectively), but the highest heterosis was observed in R29 × A212 and R19 × A212 (182 and 181%, respectively) suggesting that the incidence of heterosis is related to the relative performance of both the parents and hybrids. The results confirmed the heterosis expression for most of the agronomic traits. The heterosis for the days to flowering and maturity were negative. All the mid-parent heterosis (MPH) for the plant height, head diameter, stem diameter and achene number were positive, while only the plant height was positive for the best parent heterosis (BPH). Almost all the MPH and BPH of the crosses for the achene and oil yield were positive, which indicates a considerable heterosis for the achene and oil yield. The results showed that the relative impact of the restorer (R)-lines was higher than the cytoplasmic mail sterile (CMS)-lines on the heterosis expression for the days to maturity, stem diameter, achene number per head and achene and oil yield. The CMS-lines had more of an impact on the heterosis expression for the plant height and the relative impact of the R-lines and CMS-lines were almost similar for the days to flowering, head diameter, achene weight and oil content. Due to the higher relative impact of the paternal lines on the heterosis expression for half of the studied characteristics in this study, choosing suitable parental lines will have a crucial role in breeding the sunflowers for a desired trait.

Red pigmentation of the skin is an important consumer trait in peach (Prunus persica). The pigment consists largely of anthocyanin. Here, a transcriptomic contrast, based on RNA-Seq technology, was drawn between a white-skinned (Feitao) and a red-skinned (Qiuxue) peach cultivar. The analysis identified 2407 genes as differentially transcribed in the fruit skin of the two cultivars. Among these were a number of genes known to contribute to anthocyanin synthesis. A quantitative real-time PCR assay was used to validate the RNA-Seq-based estimates of transcript abundance for 14 differentially transcribed genes. Anthocyanin synthesis was observed in the skin of Qiuxue fruit during the late ripening stage, matching the high transcript abundance of the gene encoding UDP glucose: flavonoid 3-O-glucosyltransferase, the final step in the synthesis of anthocyanin.

The following updates have been proposed for the XYZ system for the production of hybrid wheat: The waxy characteristics of the grain were used as a classifying mark. The candidate pollen sterility gene TIP2 was detected in silico based on similarity to known pollen sterility genes in rice. In order to maintain a sterile maternal component, the addition chromosome 7H was proposed, carrying wild-type alleles Waxy-H and TIP2-H. The concept of practical production of the commercial F₁ seed was designed.

Armeniaca cathayana, a new species described in 2010, belongs to gametophytic self-incompatibility (GSI) system which is under S-allele control. One new non-S-ribonuclease (non-S-RNase) was found in A. cathayana through comparing its nucleotide and amino acid sequences with sequences of the S-allele in Genbank. The BLAST analysis showed that the one new non-S-RNase S68-RNase (GenBank Accession No. MH155952) had the highest 96% nucleotide sequence homology with Prunus webbii non-S-RNase PW₁ (EU809938.1). Alignment of deduced amino acid sequences of A. cathayana S68-RNase shared 83% similarity with P. webbii PW₁. The new non-S-RNase determined in this study will provide new information to GSI of Rosaceae.

Manganese (Mn) is an important micronutrient for growth and development in plants, however, excess Mn is harmful by disrupting photosynthesis system and inducing oxidative damage in leaves. MicroRNAs (miRNAs) play key roles in regulating Mn toxicity tolerance in plants. Here, we identified Mn toxicity-responsive miRNAs in Arabidopsis by using small RNA sequencing. Eighteen differentially expressed miRNAs were identified in Arabidopsis thaliana seedlings in response to Mn toxicity. These differentially expressed miRNAs are involved in regulating nutrition homeostasis, transport, stress response, and developmental processes. Our results indicated that these miRNAs play a key role in Mn toxicity response in plants.

To estimate genetic relationships among 31 cultivated and 34 wild grape accessions originating from regions near the Caspian Sea in the Azerbaijan Republic, RAPD analysis was performed with 27 decamer primers selected from a total of 55 primers. The most discriminating primers were OPC-16, OPF-18 and OPA-17, which showed the highest values of genetic diversity (0.927, 0.914 and 0.909, respectively). The lowest values of diversity pertained to the markers OPA-1 (0.615) and V-20 (0.624). The cluster analysis representing genetic similarity among all selected samples divided the genotypes into nine separate groups at similarity index 0.508. Within the studied Azerbaijan grape populations the highest genetic diversity belonged to the population of cultivated samples originating from the Absheron peninsula, with a diversity index 0.852 and the next ranks were assigned to the wild populations originating from Nabran and Guba regions, with a diversity index 0.824 and 0.793, respectively. The lowest diversity was observed within Davachi individuals, with a diversity index 0.765. The wild population from Azerbaijan was molecularly similar to the cultivated gene pool from this area. This result supported the hypothesis that the southwest of the Caspian Sea is a region where grape was brought into culture. During the analysis a special band was observed which could be used in identifying wild and cultivated grape accessions with high or low resveratrol content. The results of this work clearly indicated that the RAPD analysis can be used to estimate genotypic similarities, genetic diversity and for clustering cultivated and wild grape accessions.

Sharka disease caused by the infection with the Plum pox virus (PPV) in stone fruit trees is worldwide the most devastating for stone fruit production. Until now, good sources of resistance to PPV within the peach group have not been available. There are no commercial cultivars of peach that are resistant to PPV. Other Prunus species are known to show varying levels of resistance. Interspecific hybrids GF 677 (Prunus amygdalus × P. persica) and Cadaman (P. davidiana × P. persica) were revealed to be resistant to PPV. The resistance to a Dideron isolate of the descendants of Cresthaven × GF 677 and Cresthaven × Cadaman and their progenitors was evaluated after inoculation by chip-budding in a sealed screenhouse. Results demonstrate a certain level of resistance in both progenies of interspecific hybrids and indicate a potential for PPV resistance transfer to commercial peach cultivars but it will be necessary to perform backcrosses with peach cultivars of agricultural interest in order to return pomological and agronomic traits. For the definitive confirmation of resistance/susceptibility it will be necessary to wait until the adult stage of hybrids.

The phenomenon of chromatin migration was observed during microsporogenesis in an ethyl methane sulphonate (EMS) treated population of poppy, which is an important medicinal plant. Cytomixis occurred through a cytoplasmic channel or by direct fusion of pollen mother cells (PMCs); the former was more recurring than the latter. The process was associated with irregular meiosis. PMCs with differing chromosome numbers from the normal diploid number (2n = 22) through cytomixis may lead to the production of aneuploid and polyploid gametes. An increase in the concentration of EMS had a positive effect on the percentage of PMCs showing cytomixis. In addition to cytomixis, other chromosomal abnormalities were also found. Cytomixis along with the related chromosomal abnormalities largely affected the post-meiotic products resulting in some pollen sterility.

The genus Allium (Family: Alliaceae) is the most important among the bulbous vegetable crops. characterization of Alliums based on phenotypic traits is influenced by the environment and leads to biased diversity estimates. Recognizing the potential of DNA markers in plant breeding, researchers have adopted the molecular markers for marker-assisted selection (MAS), quantitative trait loci (QTL) mapping and characterization of different quality traits in Alliums. This review presents details about the use of DNA markers in Alliums for cultivar identification, diversity studies, SSR development, colour improvement, total soluble solids (TSS), cytoplasmic male sterility (CMS) and efforts of DNA sequencing. As there are no such reports to describe the above work under a single heading, we decided to mine literature for those who are working in onion, garlic, chives and leek improvement to generate new insights in the subject.

In 2009-2011 virulence of the wheat leaf rust population was studied on Thatcher near-isogenic lines with Lr1, Lr2a, Lr2b, Lr2c, Lr3a, Lr9, Lr11, Lr13, Lr15, Lr17, Lr19, Lr21, Lr23, Lr24, Lr26 and Lr28. Samples of leaf rust were obtained from different parts of the Slovak Republic. A total of 122 wheat leaf rust isolates were analysed. Resistance gene Lr19 was effective to all tested isolates. Virulence to Lr9 was found, however only in one isolate. Gene Lr24 conditioned resistance to almost all rust collections. A lower frequency of virulence to Lr2a and Lr28 was also observed. Nineteen winter wheat cultivars grown in Slovakia were tested with 8 leaf rust isolates. Winter wheat cultivar Bona Dea was resistant to all isolates applied in the greenhouse test. Presence of Lr genes was estimated according to the reactions of the tested cultivars. Presence of Lr10, Lr26, Lr34 and Lr37 was studied by molecular markers.

Mulberry (Morus L.) is an economically important tree being cultivated for its leaves to rear the silkworm Bombyx mori. Rearing of silkworm is an art and science popularly known as sericulture; an agrobased cottage industry provides employment to millions in China, India, Korea, Vietnam, etc. Mulberry is a perennial tree that maintains high heterozygosity due to the outbreeding reproductive system. It is recalcitrant to most of the conventional breeding methods, yet considerable improvement has been made in leaf yield and leaf quality. Conventional breeding in mulberry is a tedious, labour intensive and time taking process, which needs to be complemented with modern biotechnological methods to speed up the process. This article enumerates the problems, challenges, constraints and achievements in mulberry breeding along with recent advances in biotechnology and molecular biology to enable mulberry breeders to tackle specific problems more systematically and effectively.

The aim of the study was to select wheat-Aegilops biuncialis addition lines carrying Aegilops biuncialis chromosomes differing from those which were introgressed into the wheat-Ae. biuncialis addition lines produced earlier in Martonvásár, Hungary. In the course of the experiments new wheat-Ae. biuncialis addition lines carrying chromosomes 2U^b, 6M^b, 6U^b; 5U^b, 3U^b, 7U^b; 5M^b, 6M^b and 7M^b were selected. The 2U^b disomic addition line is relatively stable, as 91% of the progenies contain this chromosome pair. The 6M^b disomic addition line proved to be dwarf and sterile, but it still exists as a monosomic addition line. Progenies analysed from the 6U^b monosomic addition line did not carry the 6U^b chromosome. One plant containing the 5U^b, 3U^b and 7U^b chromosomes and one plant carrying 5M^b, 6M^b and 7M^b chromosomes showed very low fertility. Each of the plants produced a single seed, but seeds of the parent plants are still available. Line No. 49/00 carried a submetacentric Ae. biuncialis chromosome pair and the chromosome number 44 has been constant for several generations. After FISH no hybridisation site was observed on the Ae. biuncialis chromosome pair using the pSc119.2 and Afa family repetitive DNA probes, so it was not possible to identify the Ae. biuncialis chromosome pair. However, the use of wheat SSR markers and the (GAA)_n microsatellite DNA probe allowed it to be characterised more accurately. These new lines facilitate gene transfer from Ae. biuncialis into cultivated wheat and the selection of U and M genome-specific wheat SSR markers.

Cold-stored potato tubers gradually accumulate reducing sugars. A proposed reason is a cold-induced blocking of glycolysis. The introduction and expression of the bacterial gene Lbpfk coding for cold-tolerant phosphofructokinase might counteract this effect. We have recently introduced this gene into several Czech potato cultivars. The obtained transgenic lines were then tested for three years in field trials. In 17 transgenic lines derived from two of the cultivars we have investigated the accumulation of reducing sugars during two and four months of cold storage. Although in all transgenic lines the sugar content still increased between the 2^nd and the 4^th month of cold-storage, the level of reducing sugars was in all transgenic lines after both two and four months of cold storage considerably lower than in the original cultivars. The extent of sugar accumulation was also influenced by the parental genotype. No significant differences in sugar accumulation were observed between the transgenic lines from the same parent.

A large number of resistances to powdery mildew (Blumeria graminis f.sp. hordei) and their combinations are known in barley (Hordeum vulgare L.). A similarity of resistance spectra between cultivars carrying the resistance Bw, designated for the winter barley cultivar Borwina, and the near-isogenic spring barley line P15, which carries the resistance Ru2, derived from the landrace Rupee, was found. The objective of this study was to test the difference between resistances Bw and Ru2. Six cultivars were tested, four with Bw and two with Ru2. Testing with 40 isolates showed identical reaction spectra between both groups. Testing of the cultivar Kompolti 4 (Bw) and line P15 (Ru2) with 300 isolates confirmed this result. Thus, the resistances currently designated Bw and Ru2 can be regarded as identical, and are determined by the gene Ml(Ru2). Both Bw and Ru2 should be designated by the earlier code, Ru2.

This review describes sources of structures of non-microspore origin observed in anther and microspore cultures. Various characteristics of these structures may cause a wrong diagnosis of these structures as embryos or cell/tissue clusters of microspore origin. Here we suggest such structures to be named as pseudo-embryogenic structures. The introduction of pseudo-embryogenic structures and their origins could be helpful to distinguish them from true microspore-derived structures. Prompted by certain environmental cues, somatic cells existing as a contamination in immature pollen (microspores) cultures can lead to the formation of 'pseudo-embryos' commonly known as embryoids. The pseudo-embryogenic structures may be classified in the following groups: (i) pseudo-star-like structures; pseudo-multicellular structures; (ii) pseudo-embryos with pseudo-suspensors; (iii) contaminating bacteria appearing as callus colonies; (iv) calli and embryos of somatic origin; (v) giant tetrad-like structures; (vi) anther wall cells. The exact origin of these structures is discussed in this paper, and some recommendations are proposed in order to avoid misinterpretation.

In this contribution actual results of the Czech national ring tests of disease resistance in wheat are presented that are performed at 3-5 locations each year. Special attention was paid to possibilities of increasing resistance to rusts, powdery mildew, Fusarium head blight and brown leaf spot diseases. New sources of resistance to the above-mentioned diseases were detected and described. Achievements and prospects of wheat breeding for resistance to these diseases, as well as to other important diseases and pests (common and dwarf bunt, eyespot and stem base diseases, barley yellow dwarf virus, orange wheat blossom midge) are discussed.

Changes in genetic diversity of peas bred in the Czech Republic and in former Czechoslovakia since the mid-20^th century were analysed using 38 molecular marker loci, including retrotransposons and microsatellites, differentiating a total of 84 alleles. Both marker types were comparably effective in revealing the genetic diversity, with a high correlation (r = 0.81), although the pairwise genetic distances of each marker type differed. In total, 175 accessions, selected from the Czech pea gene bank collection and representing the pea cultivars collected or bred in the country, were divided into three groups according to their date of sampling or variety registration. The first group contained 70 old cultivars and landraces collected prior to 1961. The second group contained 46 cultivars released from 1961 to 1980. The third group contained 59 cultivars released between 1981 and 2004. In spite of the decline in several diversity measures, differences in allele frequencies and even allele loss in three microsatellite loci were recorded over the 70-year period, while these differences between the groups were not statistically significant. In addition, genetic heterogeneity was detected in 29 accessions (15%). This indicates that although no genetic erosion could be observed since then, it is important to monitor the genetic diversity, furthermore it highlights the vital role of germplasm collections for the crop diversity conservation.

Leaf rust caused by Puccinia triticina is the most important disease among the three rusts of wheat in Bangladesh. The disease occurs in all wheat growing areas of the country with varying degrees of severity. Stem rust caused by P. graminis f.sp. tritici was last observed during the mid 1980s, while yellow rust caused by P. striiformis f.sp. tritici occurs occasionally in the north-western region, where a relatively cooler climate prevails during the winter months. None of the rusts has yet reached an epidemic level, but damaging epidemics may occur in future, particularly if a virulent race develops or is introduced. The genes conferring rust resistance in the breeding lines and wheat varieties released in Bangladesh were investigated at CIMMYT-Mexico and DWR-India. The resistance genes Lr1, Lr3, Lr10, Lr13, Lr23 and Lr26, Sr2, Sr5, Sr7b, Sr8b, Sr9b, Sr11 and Sr31; and Yr2KS and Yr9 were found. An adult plant slow rusting resistance gene Lr34 was also identified in some of the breeding lines and varieties based on the presence of clear leaf tip necrosis under field conditions. Considering the possible risk of migration of the devastating Ug99 race of stem rust into the Indo-Pak subcontinent, the Bangladeshi wheat lines and cultivars are being regularly sent to KARI in Kenya for testing their resistance against this race. The resistant lines have been included in multi-location yield trials and multiplied for future use in order to mitigate the threat of Ug99. The resistant lines have also been included in crossing schemes to develop genetic diversity of rust resistance.

The fungus Ramularia collo-cygni is increasingly important as the causal agent of Ramularia leaf spot (RLS), a novel leaf spot disease of barley. The work aimed to identify gene resources suitable for developing new breeding lines of winter barley with improved resistance. During the first experimental period (2001-2005), RLS incidence was monitored in 711 cultivars and advanced breeding lines. Differences were detected in the intensity of symptomatic expression, but no material showed high resistance. During the second experimental period (2006-2009), response to natural RLS infection was evaluated in 19 winter barley cultivars (12 six-row and 7 two-row) registered in the Czech Republic. Highest susceptibility was detected in 6-row cvs. Luran, Laverda and Wendy while cvs Breunskylie (2-row), Merlot and Highlight (both 6-row) showed relatively lower disease incidence. High resistance was not detected. On average, 2-row cultivars showed lower intensity than 6-row cultivars and significant variation was observed among years.

Approximately 20 years ago, we began our efforts to understand grain yield in winter wheat using chromosome substitution lines between Cheyenne (CNN) and Wichita (WI). We found that two chromosome substitutions, 3A and 6A, greatly affected grain yield. CNN(WI3A) and CNN(WI6A) had 15 to 20% higher grain yield than CNN, whereas WI(CNN3A) and WI(CNN6A) had 15 to 20% lower grain yield than WI. The differences in grain yield are mainly expressed in higher yielding environments (e.g. eastern Nebraska) indicating genotype by environment interactions (G × E). In studies using hybrid wheat, the gene action for grain yield on these chromosomes was found to be mainly controlled by additive gene action. In subsequent studies, we developed recombinant inbred chromosome lines (RICLs) using monosomics or doubled haploids. In extensive studies we found that two regions on 3A affect grain yield in the CNN(RICLs-3A) with the positive QTLs coming from WI. In WI(RICLs-3A), we found a main region on 3A that affected grain yield with the negative QTL coming from CNN. The 3A region identified using WI(RICLs-3A) coincided with one of the regions previously identified in CNN(RICLs-3A). As expected the QTLs have their greatest effect in higher-yielding environments and also exhibit QTL × E. Using molecular markers on chromosomes 3A and 6A, the favorable alleles on 3A in Wichita may be from Turkey Red, the original hard red winter wheat in the Great Plains and presumably the original source of the favorable alleles. Cheyenne, a selection from Crimea, did not have the favorable alleles. In studying modern cultivars, many high yielding cultivars adapted to eastern Nebraska have the WI-allele indicating that it was selected for in breeding higher yielding cultivars. However, some modern cultivars adapted to western Nebraska where the QTL has less effect retain the CNN-allele, presumably because the allele has less effect (is less important in improving grain yield). In addition many modern cultivars have neither the WI-allele, nor the CNN-allele indicating we have diversified our germplasm and new alleles have been brought into the breeding program in this region.

Micronutrient malnutrition, resulting from dietary deficiency of important minerals such as zinc (Zn) and iron (Fe), is a widespread food-related health problem. Genetic enhancement of crops with elevated levels of these micronutrients is one of the most cost effective ways of solving global micronutrient malnutrition problem. Development and dissemination of high Zn and Fe containing high-yielding, disease-resistant wheat varieties by International Maize and Wheat Improvement Center (CIMMYT) is initially targeted for the Indo-Gangetic plains of South Asia, a region with high population density and high micronutrient malnutrition. The most promising sources for grain Zn and Fe concentrations are wild relatives, primitive wheats and landraces. Synthetic hexaploids were developed at CIMMYT by crossing Aegilops taushii and high Zn and Fe containing accessions of T. dicoccon. Current breeding efforts at CIMMYT have focused on transferring genes governing increased Zn and Fe from T. spelta, T. dicoccon based synthetics, land races and other reported high Zn and Fe sources to high yielding elite wheat backgrounds.

Wild Triticum and Aegilops species are increasingly used in wheat breeding programmes around the world as donors of genes conferring resistance to biotic and abiotic stresses, as well as of genes that contribute to the improvement of grain quality. In the present study, thirty-nine accessions of diploid species with the A genome (Triticum boeoticum and T. urartu) were evaluated for the presence of the genes conferring resistance to powdery mildew (Blumeria graminis) and leaf rust (Puccinia recondita) using both inoculation tests and sequence tagged sites (STS) marker analyses in order to find correspondence between STS markers and resistance as a trait. The most resistant entries were T. boeoticum accessions. All the marked Lr and Pm resistance genes (Pm1, Pm2, Pm3, Lr10, Lr47, Lr25 and Lr28) were identified in the check T. aestivum cultivar Bezostaya 1. The resistance to powdery mildew in the material studied was conferred by the combination of the Pm1 gene with either Pm2 or Pm3. The Pm1 and Pm3 markers appeared to be suitable for tracking these powdery mildew resistance genes, while the Pm2 gene marker cannot be considered as usable in various genetically different wheat accessions. The presence of the genes Lr25, Lr28 and Lr47 seems to be particularly useful for obtaining leaf rust resistance in T. boeoticum and T. urartu species.

Septoria tritici blotch (STB), caused by the fungus Mycosphaerella graminicola (asexual stage: Septoria tritici), is one of the most economically important diseases of wheat worldwide. During the past decade 13 genes for resistance to STB have been identified and several molecular markers have been developed. However, analysis of resistance gene expression and utility for plant improvement programs would be increased if the resistance genes were isolated in a common susceptible background. To address this problem, a program was begun to backcross resistance genes Stb1-8 into two susceptible wheat cultivars. Work with genes Stb2, Stb3, Stb6 and Stb8 has proceeded the farthest. Resistance gene Stb3 is dominant, while Stb2 may be recessive. This will be the first report of recessive resistance to STB if confirmed. Molecular markers linked to the resistance genes are being validated in the backcross progeny and should provide the materials for efficient introgression of these genes into elite germplasm for future wheat improvement.

Compared to the large effort spent developing Brazilian bread wheat cultivars, relatively few soft wheat cultivars for cookie flour were released in this country in the recent years. The objective of this study is to propose a model to predict wheat cultivars with improved manufacturing quality for the cookie industry while maintaining production for the growers. A database was compiled originally with 1674 entries with field, milling and flour quality parameters from the year 2000 to 2008 crop seasons. The critical specifications of 14 commercial cookie flours were compared and it was determined that the variables farinograph water absorption appeared in 14 out of 41 specifications (34.1%), alveograph strength appeared in 13 out of 41 specifications (31.7%), wet gluten appeared in 11 out of 41 specifications (26.8%), alveograph tenacity appeared in two out of 41 specifications (4.9%), and alveograph dough extensibility appeared in one out of 41 specifications (2.5%). Using frequency percentages as model coefficients a Brazilian Cookie Wheat Score Model was proposed:BCWS =ABS × 0.341 + W × 0.317 + WG × 0.268 + P × 0.049 + L × 0.025. The ideal score for a wheat genotype to be classified as cookie wheat for the Brazilian market is within the optimum interval from 56.1 to 81.2. To validate this model and its proposed interval, 277 wheat entries from the 2008 crop year were tested under the following conditions: first, wheat genotypes that yielded less than the average of bread wheat genotypes were discharged; second, wheat genotypes without the full set of values for the model variables were discharged. Twenty wheat genotypes, out of 277, were within the optimum interval and were proposed as wheat genotypes to produce cookie flour. The validation results indicated that, using the BCWS Model, along with the established conditions, a wheat breeder will have 75% chance of finding a potential cultivar with acceptable cookie functionality from a set of experimental lines.

The resistance Heils Hanna (HH) was postulated in several tens of 471 previously tested winter barley cultivars. In this paper, new tests on 29 of these cultivars are reported. Thirty-two reference isolates of Blumeria graminis f.sp. hordei held in the pathogen genebank at the Agricultural Research Institute in Kromeriz, Ltd. including a Japanese isolate and five Israeli isolates were used for response tests. However, the resistance HH conferred by the gene Mla8 and herein characterised by reaction type 0 to an old Japanese isolate known as Race I was now postulated only in four cultivars. In the other 25 cultivars another resistance, characterised by reaction type 0 to Race I and also to two Israeli isolates, was detected. In addition to the two mentioned resistances, eight known (Bw, Dr2, Ha, IM9, Ln, Lv, Ra and Sp) resistances were found in the set examined. Lomerit was the only registered cultivar tested here in which the newly detected resistance was present alone, therefore, it is recommended that this resistance be designated Lo.

Bread-making quality of wheat flour is influenced by wheat storage proteins. The percentage of sodium dodecyl sulphate (SDS)-unextracted polymeric proteins in total polymeric proteins (% UPP), as one important factors determining bread-making quality, is largely influenced by the individual and interactive effect of genetical background and environmental conditions. Four spring wheat cultivars were grown in green house. Two of the cultivars have high molecular weight glutenin subunits 5+10 while the other two have 2+12. Four different nitrogen regimes and two different temperature levels (distinguished as low and high temperature) were used. The results highlighted the importance of interactive influence of cultivars, nitrogen regimes and temperature levels for creating differences in the amount of % UPP during grain maturation period (GMP) and at maturity. The shift to end up with either high or low % UPP at maturity happened early during GMP (around 12 days after anthesis). Influences of cultivars on % UPP was found early during the GMP while influences of temperature and nitrogen regimes were seen much later during the GMP. The results will help in understanding the relationship between quality parameters of wheat flour and how these are influenced by different environmental and genetic factors.

The presence of genes for resistance to scab (Venturia inaequalis) and powdery mildew (Podosphaera leucotricha) was studied using molecular markers in a sample of 279 apple cultivars from the Czech collection of apple genetic resources. The sample comprised 37 cultivars supposed to have the Vf gene for scab resistance, 97 reference world cultivars and 145 old and local cultivars. Six PCR molecular markers for the scab resistance genes Vf, Vm, Vbj, Vr and Vh and three PCR molecular markers for the powdery mildew resistance genes Pl-w, Pl-1 and Pl-d were used. The marker for the major scab resistance gene Vf was detected in all cultivars supposed to have Vf, except in Romus 1, and in the three small-fruited cultivars Malus Evereste, Golden Gem and Hilleri. The markers of the Vr and Vh scab resistance genes were detected in 22 cultivars in combination with the marker for Vf, in 56 reference world cultivars and in 82 old and local apple cultivars. PCR molecular markers for one or two of the powdery mildew resistance genes were detected in the small-fruited cultivars Malus Evereste, Golden Gem, prof. Sprengeri and Hilleri; and in the larger fruited cultivars Hagloe Crab, Borovinka and Tita Zetei. We did not find markers for the scab resistance genes Vm and Vbj in any of the studied cultivars. They are absent also in the remaining part of the Czech collection of apple genetic resources. PCR molecular markers are useful tools for the identification of resistance genes within apple germplasm collections and can be used to increase the number of sources for disease resistance in breeding programmes.