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Crop yields are reduced by 70-80% due to a water stress situation specifically during the reproductive stage and are not able to fulfil the needs of food requirement in developed and developing countries of the world. Earlier work was mainly focused on the use of morphological or physiological and molecular aspects for improved stress tolerance. Efforts are being made to overcome this problem with the help of today's sophisticated and advanced technology through genomics, proteomics and metabolomics. The presented model summarizes our work in the last five years to mine anatomical parameters as a novel approach to further improving introgression or exploitation of stress adaptive traits. We have focused on some key anatomical traits playing a substantial role in water stress tolerance. This new conceptual model encompasses increased palisade mesophyll height, higher leaf strength index (LSI), higher number of conducting tissues with increased diameter in leaf, stem and root and controlled transpiration rate due to a lower number of stomata per unit leaf area along with the increased guard cell size. Different plants viz. Lycopersicon esculentum, Capsicum annuum, and Calotropis gigantea were screened by developing polyploids to validate this model approach. Genotypes of Vitis vinifera and Solanum melongena were also screened. Wild relatives like Lycopersicon esculentum var. cerasiforme and Solanum khasianum were evaluated for comparison. These observations were further correlated with various stress adaptation traits like yield under stress, in vitro screening, chlorophyll content, transpiration heating and cooling, molecular markers etc. A new scoring method is proposed which will be helpful to screen a large set of germplasms on a preliminary basis to discriminate genotypes for drought tolerance. There is an urgent need to study the genetics of these stress adaptive traits using high throughput molecular markers to make them more useful for a higher magnitude of genetic gain.

The results of evaluation of powdery mildew resistance in winter barley varieties in 285 Czech Official Trials conducted at 20 locations were analysed. Over the period, the number of varieties tested per year increased from four to seven in 1976-1985 to 53-61 in 2002-2005. To assess the resistance of varieties, only trials with sufficient disease severity were used. In 1976-2000, six varieties (1.7% of the varieties tested in the given years) ranked among resistant (average resistance of a variety in a year > 7.5) including NR-468 possessing the gene Mla13, KM-2099 with mlo and Marinka with the genes Mla7, MlaMu2. In 2001-2005, already 33 varieties (16.9%) ranked among resistant, of which Traminer possessing the genes Ml(St) and Ml(IM9 dominated. The proportion of susceptible varieties (average resistance ≤ 5.5) did not change in the two mentioned periods. Two-rowed varieties began to be tested as late as in 1990 (the first variety was Danilo), however, no difference was found in the resistance of two- and six-rowed varieties. Using an example of two pairs of varieties (Dura-Miraj and Marinka-Tiffany) with identical genes for specific resistance but with different resistance in the field, the efficiency of non-specific resistance is discussed. The resistance of domestic and foreign varieties was similar in 1994-2000; however, in 2001-2005 the difference was 0.75 point to disadvantage of domestic ones.

The disease caused by Tomato spotted wilt virus (TSWV) belongs to the most destructive diseases of tomato all over the world. Therefore, tomato has been subjected to many breeding efforts, including the incorporation of resistance to the virus. Recently emerged approaches, ideas and technologies could affect the future direction of the virus resistance breeding. In particular molecular techniques have provided opportunities in the form of linked molecular markers to speed up and simplify the selection of host resistance genes. Transformation of an inbred tomato line with the TSWV nucleoprotein gene cassette resulted in high levels of resistance to TSWV that have been retained in the hybrids derived from the parental tomato line. These and other techniques offer great opportunities for improving the virus resistance and, therefore, it is time to reconsider the future direction of resistance breeding in tomato. The effort has been made to review available sources of resistance, conventional breeding methods, marker-assisted selection, pathogen-derived resistance and transgenic resistance approaches in this paper.

Emmer and spelt are two hulled wheats that were widely grown in Spain until the latter 1960s. Twenty-nine emmer and twenty-six spelt lines obtained from Spanish accessions of these hulled wheats were analysed for quality traits and endosperm storage protein composition. The results showed a wide range of variability in these traits. Likewise, a certain association between some alleles of these proteins and the SDS-sedimentation volume has been detected.

Wild potato species (genus Solanum, section Petota) represent a tremendously diverse gene pool which is traditionally utilized as a source of diverse traits for potato breeding. Abiotic and biotic stress tolerance and resistance belong to the most frequently utilized traits of wild species in potato breeding programs. This review provides an introduction to the taxonomy, centre of diversity, genetic characteristics, evolution and important tolerance and resistance traits of wild potatoes and their use for potato breeding. The review has been written for readers who are interested in the problems of finding and utilization of new resistance genes from the wild genetic resources.

The genetic diversity of 35 yellow-seeded Brassica napus L. accessions originating from China, Czech Republic and Poland was assessed by means of Amplified Fragment Length Polymorphism (AFLP) markers based on multiplex PCR using multi-colour fluorescent-labelled primers. Five brown-seeded accessions originating from China and France were selected as outliers. In total, 632 peaks were generated by AFLP reaction using 18 primer combinations. Only distinctly polymorphic markers among them were scored. In total, 242 polymorphic markers were detected with an average of 13.4 markers per primer combination. The AFLP analysis separated forty studied accessions into Chinese and European groups by UPGMA clustering and Principal Coordinates Analysis (PCA). The grouping of accessions based on the cluster analysis and PCA was generally consistent with known pedigree information and geographic origin. Notable geographical divergence was found between Chinese and European yellow-seeded accessions. This information is useful for yellow-seeded hybrid breeding and encouraging breeders to exchange their germplasm as to enlarge the genetic diversity of breeding accessions.

Proteomic techniques that allow the identification and quantification of stress-related proteins, mapping of dynamics of their expression and posttranslational modifications represent an important approach in the research of plant stresses. In this review, we show an outline of proteomics methods and their applications in the research of plant resistance to various types of stresses.

Emmer wheat (Triticum dicoccum Schübl. or also T. dicoccon Schrank) tetraploid wheat species was grown in the Czech territory till the 6th century A.D. when it was replaced by bread wheat. At present only landraces and wild forms of this species are available in collections of genetic resources. With the aim to extend the spectra of grown crops, a collection of emmer genetic resources in the Czech Gene Bank was studied. An accession later in ripeness, with a good level of resistance to fungal diseases and with a high yield potential was selected from the collection. After bulk selection procedure and three year testing it gained a certificate of legal protection as cultivar Rudico. The cultivar with high protein content and very good resistance to fungal diseases was found to be able to meet the requirements for organic growing systems as well.

An improved protocol for Brassica protoplast culture and plant regeneration was developed. Isolated protoplasts from four-weeks-old in vitro shoot tip culture of Brassica oleracea var. botrytis cv. Siria F1 and Brassica napus doubled haploid of breeding line OP-1 were cultured at a density of 9.8-11.2 × 10⁴ protoplasts/ml in darkness at 25°C in a modified medium containing 2% glucose, 0.25 mg/l 2,4-D, 1 mg/l BAP and 1 mg/l NAA. The first divisions of protoplasts were observed on the third day of culture in B. oleracea and on the fourth day in B. napus. The protoplast cultures were diluted with low osmotic medium on 7^th and 11^th day. The frequency of dividing cells was about 80% in B. oleracea and 50% in B. napus. After one month, the microcalli of approximately 0.5-1 mm in size were transferred into an induction medium with various combinations of growth regulators. Minimum duration of enzyme treatment time and extended dark period in the initial phase of culture increased the survival rate of protoplasts. Organogenesis started when the calli enlarged in size on an induction medium (1 mg/l NAA, 0.02 mg/l GA₃, 1 mg/l 2iP) with 2% sucrose and 0.8% agar. Regeneration frequency of calli was found to be 69-75% in B. oleracea and 2-3% in B. napus. Well-developed shoots were transferred for rooting to a half-strength MS medium without growth regulators. More than 100 B. oleracea regenerants were transferred into soil, and they produced normal heads and set seeds. This very simple procedure is efficient and suitable mainly for B. oleracea var. botrytis and represents a background for fusion experiments.

A set of quality parameters (crude protein content, Zeleny sedimentation test, wet gluten content, gluten index, albumins + globulins content, gliadin content, sum of glutenins, proportion of albumins + globulins in crude protein and relative viscosity) was tested in 17 doubled haploid (DH) wheat lines differing in the presence or absence of 1B/1R translocation. The presence of 1B/1R translocation (allele Gli 1B3) affected the significantly higher content of albumins and globulins and significantly lower value of gluten index. Nevertheless, a certain translocation influence on the other parameters (Zeleny sedimentation test; relative viscosity; proportion of albumins + globulins in crude protein) was also registered. The deteriorative effect of the 1B/1R translocation on indirect technological grain parameters was confirmed more markedly in gluten index than in Zeleny sedimentation test. A high number of significant differences between lines was found in Zeleny sedimentation test, content of glutenin, content of albumins + globulins and their proportion in crude protein. In spite of lower variability between lines relative viscosity showed a high dependence on genotype and was indifferent to the other quality parameters.

Progression of deoxynivalenol (DON) concentrations in spikes and kernels was studied in relation to Fusarium head blight (FHB) symptoms in five winter wheat cultivars, differing in resistance to FHB, after single floret inoculation with an aggressive isolate of Fusarium culmorum. After inoculation in field conditions the spikes were detached from the plant and kept in the greenhouse under controlled conditions. High concentrations of DON were detected in susceptible cultivars at an early stage of pathogenesis (7 days after inoculation). Over the whole examined 21-day period and also at maturity spikes contained more DON than kernels. While differences between cultivars in the accumulation of DON were highly expressed already 7 days after inoculation, differences in symptomatic reactions were not clear until day 21. Owing to the reported crucial role of DON at early stages of pathogenesis, the importance of appropriate timing of fungicide application is highly stressed.

The modified PAGE method (TRIS - Glycine buffer pH 8.9) was used for the characterisation of selected 25 registered potato varieties. This method enabled to identify each variety from the examined variety set. The calculation of identity indexes (proportion of common bands) helped to evaluate the similarity of varieties from these aspects. The examination of electrophoretic profiles of soluble tuber proteins, which are highly polymorphic and stable, can be considered as valuable for variety characterization and identification.

Perennial ryegrass (Lolium perenne L.) is the most important grass species used in temperate grassland agriculture. Our objective was to obtain an overview of the genetic relationships between 20 individual genotypes of perennial ryegrass of diverse origins, using amplified fragment length polymorphism (AFLP), inter-simple sequence repeat (ISSR), random amplified polymorphic DNA (RAPD) and two sets of simple sequence repeat (SSR) markers. All 20 individuals were uniquely fingerprinted by all four marker systems and comparisons were made on the basis of 85 markers each. Mean genetic similarities were estimated at 0.31, 0.43, 0.23 and 0.15 for AFLPs, ISSRs, RAPDs and SSRs, respectively. Cophenetic values resulted in good (AFLP and SSR-B = 0.88) to moderately good fits (ISSR = 0.76, RAPD = 0.70, and SSR-A = 0.79). Comparing the four marker systems to each other, AFLP and SSR-A were correlated best (r = 0.57). All other comparisons revealed rather low correlation coefficients in the Mantel Z test. With twice as many markers cophenetic values increased to a very good fit for AFLPs (0.90) and SSRs (0.92).