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Fusarium oxysporum Schlecht. f.sp. radicis-lycopersici Jarvis & Schoemaker (FORL) is a saprophytic fungus, responsible for the fusarium crown and root rot disease in tomato (Solanum lycopersicum L.). This is one of the most destructive pathogens of this species. A new cleaved amplified polymorphic sequence (CAPS) marker C2-25 was developed for the detection of the dominant gene Frl, which confers tomato resistance to FORL. C2-25 was amplified from a conserved ortholog set II (COSII) sequence C2_At2g38025. The XapI-derived restriction product of 700 bp was informative for the identification of FORL resistant tomato genotypes and can be used as a diagnostic marker in tomato breeding programmes and hybrid seed production.

Mendel's impact on science is overwhelming. Although based on the number of scientific papers he published he might be considered a meteorologist, his most significant contribution is his study of plant hybrids. This single work puts Mendel on a par with Darwin's evolutionary theory and establishes him firmly in the frame of today's biology. The aim of this article is to introduce the personality of Gregor Johann Mendel, focussing not just on his scientific work, but also on his background and what or who influenced him. To understand Mendel's use of quantification and mathematical analysis of obtained results, representing a radical departure from methods of his predecessors, it is important to know something about their arguments, beliefs, and practices. He designed his experiments to answer a long standing question of hybridization, not inheritance as we perceive it today, since the science of genetics was born considerably later. He studied many genera of plants, but his famous research was on garden peas. To choose a single species for his crosses was fundamental to his success, but also fuelled most of criticism at the time he presented his results. The reason for his success was partly due to being a hybrid himself: of a biological scientist, a physical scientist and a mathematician. Mendel's other fields of interest such as meteorology and bee keeping are also introduced in this article.

Farmers' preference study and informal seed dissemination was carried out through farmer participatory variety selection (PVS) during 2006-2007 to 2008-2009 by the Wheat Research Centre (WRC), Bangladesh Agricultural Research Institute (BARI), Dinajpur, Bangladesh, in collaboration with CIMMYT. Four varieties including widely grown Shatabdi and four advance lines including Ug99 tolerant BAW 1064 were tested in mother-baby trial approach in 8 villages in each year. Mother trials were researcher designed but farmer managed. However, baby trials were designed and managed by farmers themselves. Preference scores of 30 farmers for varieties were recorded two times viz., pre and post-harvest stages. Farmers' preferred BAW 1064 owing to its 10% yield superiority over the widely grown Shatabdi variety, bolder white grains, larger grains/spike, non-lodging behaviour, earliness and resistance to diseases. This variety was found moderately resistant to Ug99 in Kenya. BAW 1064 was released as BARI Gom 26 in March 2010. After three years of PVS work, 19.4 t seeds reached informally to 969 farmers of 24 PVS villages from only 252 kg source seeds supplied for trials. In 2009-2010, seed production of this variety was done in 44 ha; 33.8 ha in 111 farmers' fields and 10.2 ha in research stations. Around 150 t seeds were produced that are being used for further testing and multiplication in 2010-2011. Seed dissemination through PVS was much faster than official approach of Bangladesh Agriculture Development Corporation (BADC). Hence, for selection and dissemination of CIMMYT developed Ug99 tolerant lines, farmer-participatory approach is being deployed.

In Central Asia, stem rust (Puccinia graminis f.sp. tritici) causes considerable damage, especially during growing seasons with high rainfall. Ug99 is a race of stem rust that is virulent to the majority of wheat varieties. To develop disease-free germplasm, wheat material was screened using the predominant stem rust races of Kazakhstan and tested in two nurseries; CIMMYT-Turkey and the Plant Breeding Station at Njoro, Kenya. A total of 11 pathotypes of P. graminis f.sp. tritici were identified in Kazakhstan from the stem rust samples collected in 2008-2009. In particular, pathotypes TDT/H, TPS/H, TTH/K, TKH/R, TKT/C and TFK/R were highly virulent. Of the 170 advanced lines of wheat, 21 CIMMYT lines resistant to 5 aggressive Kazakhstani pathotypes of P. graminis were identified. A high level of resistance was observed in 11 wheat cultivars and advanced lines: Taza, E-19, E-99, E-102, E-572, E-796, E-809 (Kazakhstan), Ekinchi (Azerbaijan), Dostlik, Ulugbek 600 (Uzbekistan) and Umanka (Russia). Based on data obtained from Turkey-CIMMYT and the Plant Breeding Station Njoro, Kenya nurseries, out of 13 tested entries, 6 wheat breeding lines which were resistant to both stem and yellow rust and 10 wheat lines which showed high and moderate levels of resistance to Ug99 were selected. Using the sequence tagged site (STS) molecular marker Sr24#12, associated with Sr24/Lr24, seven wheat entries resistant to stem rust were identified. These results will assist breeders in choosing parents for crossing in programmes aimed at developing varieties with desirable levels of stem rust resistance in Kazakhstan and they will also facilitate stacking the resistance genes into advanced breeding lines.

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 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.

Six crucial questions for lucerne breeders are set up and discussed in relation to the available information. (i) Which width of adaptation? Genotype נlocation interaction is region-specific and may be wide enough to justify breeding for specific adaptation. Genotype נexploitation interaction requires contrasting plant types for mowing and intensive grazing. (ii) Can we breed very drought-tolerant varieties? One drought-tolerant landrace exhibited a drought-avoidance, water-conservation strategy based on limited root development, while large root featured material adapted to favourable environments and/or frequent mowing. (iii) Which selection scheme and variety type? Many schemes were proposed for synthetic varieties, but empirical or theoretical comparisons were limited in number and inference space. Non-additive genetic variation may be exploited by free hybrids (semi-hybrids) through procedures varying in complexity, possibly assisted by marker evaluation. Previous selection of exotic germplasm for adaptation is essential. (iv) How to improve the forage quality? Selection for modified stem morphology (increased internode number, decreased internode length) proved effective. Combined selection for forage yield and leaf/stem ratio seems also feasible. (v) Which opportunities for marker-assisted selection? Linkage maps for lucerne are available but useful markers for forage yield may be site-specific. Bulk segregant analysis is promising in breeding for stress tolerance. (vi) How to exploit genomic information from M. truncatula? This model species can help in developing markers and locating genes which control metabolic pathways, such as saponin content and composition. Information from M. truncatula on marker-trait association for forage yield or tolerance to abiotic stresses may be little exploitable.

Birdsfoot trefoil (Lotus corniculatus L.) is a perennial species that is known for its outstanding characters as a crucial component of meadow and pasture vegetation and a highly successful fodder crop. However, its cultivation has been limited by the inability to control pod shattering. The anatomic and physiological bases of pod shattering are known and are considered to be controlled by more than one gene. This paper reviews the known causes of pod shattering and potential ways of overcoming pod indehiscence in L. corniculatus. Genetic transformation is possible in the genus Lotus; however, the useful genes determining the seed pod indehiscent character have not been identified yet. The only way of introducing pod indehiscence characters into L. corniculatus is by interspecific hybridization within the genus Lotus; embryo rescue and protoplast cultures are promising. To determine useful genotypes for crosses, investigations of pre- and post-fertilization barriers are necessary. To that end, we present here a convenient procedure for a whole-mount clearing treatment of immature seeds that leaves the cell walls of tissues intact. This is a useful technique for the study of post-fertilization barriers in Lotus.

Agrimonia eupatoria, Betonica officinalis, Hypericum perforatum, Plantago media, Salvia pratensis and S. verticillata were selected as subjects for a research project studying the genetic diversity of wild medicinal plants in the Czech Republic. Some plants (both in the vegetative form and as seeds) from 26 localities at 5 protected landscape areas around the Czech Republic were transferred to the field nursery in Olomouc; there the contents of the active compounds (essential oil, tannins, hypericin and hyperforin, mucus) were evaluated. The large number of results provides a good opportunity to evaluate the quality of natural medicinal plants for pharmaceutical purposes; with regard to its origin, and to selecting starting materials for both breeding and the production of drugs.

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.

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.

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.

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.

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.

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.

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.

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.

Multiplex PCR was developed and optimized for simultaneous detection of wheat leaf rust resistance genes Lr26 and Lr37. The presence of the genes was analyzed in 21 winter wheat cultivars registered in the Czech Republic. Gene Lr37 was detected in four tested cultivars (Bakfis, Biscay, Nicol, Mulan), gene Lr26 occurred only in one cultivar (Etela) and three cultivars (Clarus, Orlando and Rapsodia) were found to carry both these genes. Data obtained by PCR markers were compared with results of greenhouse and field tests. Seedling reactions of cultivars possessing Lr26 to seven different leaf rust isolates conformed to the results obtained by the marker analysis, however, there were found some discrepancies in the detections of Lr37, which could be detected in greenhouse seedling tests only with difficulties.

The aim of this review is to summarize recent information on Fusarium head blight (FHB) in small grain cereals, especially in wheat and barley. Basic information on FHB epidemiology, types of resistance and plant resistance mechanisms is included. Standard methods for the evaluation of the individual types of FHB resistance and the extent of infection are briefly described. Special attention is paid to the sources of FHB resistance of different origin and possibility of their exploitation in cereal breeding. Unfortunately, a high level of FHB resistance was detected in non-adapted germplasm or distant relatives, which is a serious impediment to breeding progress in this field. The present state of breeding for FHB resistance in wheat, barley, rye, triticale and oats was analyzed. It was shown that large-scale QTL detections provide new opportunities for increasing the resistance; however, multi-step phenotypic selection still remains to be the most effective tool. Pedigree analyses indicated that the latest progress reached in this field was obtained through the cumulation of resistance genes coming from heterogeneous sources with different response to FHB.

Reactions to artificial infection with Fusarium graminearum isolates and a new fungicide Swing Top were studied in nine winter wheat cultivars evaluated in field experiments at two sites for three years for expression of symptoms, deoxynivalenol (DON) content in grain and grain yield. The results demonstrate a pronounced and relatively stable effect of cultivar resistance on reducing head blight, grain yield losses and contamination of grain by the mycotoxin DON. It is advantageous that the moderate level of resistance to Fusarium head blight (FHB) was detected also in two commonly grown Czech cultivars Sakura and Simila. Average fungicide efficacy for DON was 49.5% and 63.9% for a reduction in yield loss, however, it was found highly variable in different years and sites. The joint effect of cultivar resistance and fungicide treatment was 86.5% for DON and even 95.4% for reducing the yield loss. A very high risk was documented for susceptible cultivars and also the effects of medium responsive cultivars were found to be highly variable in different environments and therefore not guaranteeing sufficient protection against FHB under different conditions.

This study presents the ampelographic and molecular characterization of 44 grapevine cultivars. Ampelographic data were obtained during two vegetation periods using the latest version of the descriptors. Based on the mean values transformed by the method indicated in IBPGR publications, a dendrogram was constructed. ISSR analysis was also employed to characterize the genotypes at the DNA level. Twenty primers, selected on the basis of their discriminating potential, generated a total of 157 bands, of which 140 were polymorphic. The dendrograms constructed by the two approaches were largely similar in both the clustering position and divergence of varietal groups. The least distance was observed between Yuvarlak Cekirdeksiz and Superior Seedless. The clustering position of cultivars throughout the dendrograms was basically related to the genetic distances and main uses, as well as to geographic origins.

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 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.

Astragalus excapus L. and Astragalus austriacus Jacq. are regarded as critically endangered species in Slovakia. They are threatened by environmental impact, natural succession, as well as by human activities. Monitoring them is an important tool in determining their status and in making management decisions for their protection. In this contribution, a summary of the basic terrain endeavours, current status, locality and species description, habitat preferences, possible threats, current protection, and management activities are presented.

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.

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.