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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.

Effects of microspore culture treatment with antimitotic agents colchicine, trifluralin and oryzalin on the frequency of embryo formation, embryo development, plant regeneration and diploidization rate in three F₁ hybrids of winter rapeseed cultivars were compared. The ploidy level analysis of 1709 flowering microspore-derived plants showed that in vitro applications of all antimitotic drugs increased the rate of doubled haploid (DH) plants significantly. The mean rate of DH plants from the trifluralin treatment was 85.7%, from colchicine 74.1% and 66.5% in the case of oryzalin, while only 42.3% in the untreated control variant whereas in vivo additional application of colchicine at the plantlet stage did not significantly increase the mean rate of DH plants (55.6%). Although there were no significant differences in diploidization efficiency between the in vitro applications of particular antimitotic agents, trifluralin showed to be the most suitable because of its positive effect on embryo development and conversion into whole plants. In addition, the diploidization rate was sufficient and stable in all genotypes tested. The results indicate that the trifluralin treatment of microspore cultures could provide efficient chromosome doubling for the production of doubled haploid lines from winter oilseed rape breeding materials.

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.

In 2005, 2006 and 2007 nineteen, eight and nine spring wheat cultivars, respectively, were tested in field trials for resistance to common bunt after inoculation with bunt teliospores. Nine spring wheat cultivars were tested in a greenhouse under favourable conditions for the bunt infection. Bunt incidence in the field trials varied between 0% and 38.7%, in the greenhouse between 52.9% and 100%. The results of individual cultivars and years fluctuated. A reduction in plant height, ear length, root system and increased tillering were registered in the inoculated plants. Spots on the leaves of inoculated plants were observed in three out of the four greenhouse experiments.

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 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.

In 2003-2005 faba bean accessions were evaluated in laboratory and field inoculation tests with a mixture of differently virulent isolates for susceptibility to anthracnose caused by the fungus Ascochyta fabae Speg. All tested commercial faba bean cultivars, both colour and white flowering, were found to be susceptible or highly susceptible. The highest level of resistance was found only in declared sources of resistance: 29H, L-8 and Petra. Segregation of F₂ plants derived from the cross of cultivar Merlin (susceptible, white flowering) with line Petra (resistant, colour flowering) was observed. The plants were moderately susceptible to highly susceptible. This finding indicates a multigenic character of resistance. Repeated selection cycles with the selection of resistant plants in F₂ and F₃ generations were performed. In the F4 generation, colour flowering lines with a high level of resistance, nearly at the same level as in line Petra, were obtained. In comparison with the parental cultivar Merlin an increase in the resistance of selected white flowering lines was proved. Resistance will be increased/stabilized in further repeated selection cycles.

In ornamental gardening, Spiraea × vanhouttei is a frequently planted spirea species in the Czech Republic. In 2003, there arose a suspicion of possible occurrence of fire blight caused by Erwinia amylovora on spirea shrubs in Prague and its environs. This suspicion was disproved for a certainty. The absence of the fire blight pathogen in symptomatic spirea plants stimulates a further effort to tackle the problem of a cause of conspicuous fire blight-like symptoms or inflorescence blast occurring on some spirea shrubs. The subject of this paper is: (i) to describe symptoms, incidence and severity of inflorescence blast, bud and flower abnormalities occurring in Spiraea × vanhouttei shrubs; (ii) to find out differences in the occurrence of blasted inflorescences between Spiraea species and cultivars with the intention of verifying the hypothesis that the blast inflorescence and sterility of some spirea species are associated with hybrid species. Symptoms of inflorescence blast are every growing season. No seed is produced by blasted inflorescences. Besides inflorescence blast, aborted floral buds appeared sporadically on a small scale. Spirea species were split into four categories according to the incidence of blasted inflorescences. Out of 52 species evaluated, 10% showed no or scarce incidence, 52% medium incidence, 27% high incidence and 11% very high incidence. The scarce incidence of blasted inflorescences was connected with the high seed production. And vice versa, very high incidence of blighted inflorescences was closely connected with no or low seed production or with high incidence of sterility. Fifteen out of the evaluated spirea species are the result of hybridization. These hybrids occur in each of the four categories of spirea species distinguished by the incidence of blasted inflorescence. However, it is remarkable that the highest incidence of hybrid spireas occurs in the category with the highest incidence of blasted inflorescence (83.33%). In the remaining three categories of spirea species, the proportion of hybrids ranged from 18 to 21%. It might indicate some connection of spirea hybrids with sterility.

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.

PCR primers for diagnosis of Rhynchosporium secalis in seed samples of barley were developed. For the quantification of the pathogen in seed samples a real-time PCR with SYBR Green approach was used. Amounts from 1.8 to 419.1 pg of R. secalis DNA per 100 ng of total DNA were detected in 18 samples of barley seeds contaminated by R. secalis in field conditions. The correctness of this quantitative analysis was checked using an artificial infection of seeds with 1, 2, 5 and 20% level of infection by R. secalis. The level of contamination of artificially infected samples decreased with a lowering amount of added seed powder contaminated by the pathogen, the correlation coefficient for this analysis was 0.98. While the primer pair used in these analyses shows cross-reactions with other pathogens (P. teres, Drechslera tritici-repentis, F. culmorum and F. poe), it is recommended to check the products of RT-PCR by agarose-gel electrophoresis, in which these pathogens are easily distinguishable from R. secalis by different lengths of the amplified fragments.

The reaction of 50 winter wheat cultivars/lines to artificial infection with Pyrenophora tritici-repentis (PTR) races 1, 3, and 6 was studied under greenhouse conditions. The set of tested cultivars/lines included predominantly cultivars registered in the Czech Republic and some new breeding lines. A high level of resistance to P. tritici-repentis was detected in the cultivars Clarus, Rheia, Cubus, SHMK WW 14-92, Šárka, Vlasta and Dromos (SWS 799.14953), susceptible reactions were observed in the cultivars Caphorn, Corsaire, Karolinum, Heroldo (PBIS 00/91), Hedvika, Biscay, Svitava, Barroko (PBIS 00/140) to all three races tested. The majority of the tested cultivars possess a moderate level of resistance to PTRraces 1, 3, and 6. Significant differences were proved not only in the reaction of the tested cultivars but also in the aggressiveness of the three used isolates.

In 2001-2004 virulence of the wheat leaf rust population in the Czech Republic was studied on Thatcher near-isogenic lines with Lr1, Lr2a, Lr2b, Lr2c, Lr3a, Lr9, Lr10, Lr11, Lr15, Lr17, Lr19, Lr21, Lr23, Lr24, Lr26 and Lr28. Samples of leaf rust (180 in total) were obtained from different parts of the Czech Republic. Resistance genes Lr9 and Lr19 were effective to all tested isolates like in the previous years. Unlike the previous years virulence on Lr24 and Lr28 was observed. Relatively effective were also Lr1, Lr2a, Lr24, Lr28 and Lr2b. Other Lr genes were defeated by the majority of the tested samples. Our results transformed to the numbers of physiologic races indicate that race 61SaBa prevailed like in the previous years, followed by races 61, 2, 12SaBa, 2SaBa, 14, 77SaBa, 12, 57, 6, 53, 53SaBa, 77, and 14SaBa. Twenty-one winter wheat cultivars registered in 2001-2004 were tested with 8 leaf rust isolates. Out of them 15 showed resistance at least to one rust isolate. High resistance recorded in field trials for cvs Batis and Ilias, which were susceptible to all tested rust isolates at the seedling stage, demonstrates the importance of field (partial) resistance.

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.

Based on NIRS (near infrared reflectance spectroscopy) measurements carried out in a collection of 262 samples of winter oilseed rape with a different content of fatty acids (FA) in oil, calibration equations for the laboratory instrument Foss-NIRSystem 6500 were developed. Calibration was focused on the possibility of screening seed samples of different composition of oleic acid (C18:1), linoleic acid (C18:2) and linolenic acid (C18:3) using NIRS analysis. The reference method was gas chromatography (GC). The content of FA in segregating F₂ generations after crossing between lines with different contents of FA and lines with standard content of FA in oil ranged from 32.3 to 82.0% for C18:1, 10.2-26.8% for C18:2 and 3.3-11.8% for C18:3. The verification of a validation equation in 50 randomly selected samples of F₂ generation in the year 2006 proved high correlation coefficients (r) between NIRS analysis and GC values, r = 0.86 for C18:1, r = 0.82 for C18:2 and r = 0.85 for C18:3. Non-destructive NIRS analysis enables rapid and reliable selection of materials with different composition of FA in the seed of oilseed rape (lines with desirable high content of C18:1 and low content of C18:3).

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.

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).