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Silver nanoparticles (AgNPs) have been shown to enhance seed germination and plant growth. In this study, we examined the plant response to AgNP dosage using a model plant, Arabidopsis thaliana. Seedlings were treated with different concentrations of AgNPs. Seedling fresh and dry weights were measured for all treatments. The exposure of plants to 1 mg/l AgNPs resulted in a significant increase in seedling fresh and dry weights compared with control plants, although the exposure to lower and higher concentrations resulted in a decrease in fresh and dry weights. Expression profiling for 22 MADS-box genes was carried out using quantitative real-time PCR (qRT-PCR). Among the investigated MADS-box genes, eight genes were upregulated and four genes were downregulated at each of the AgNP concentrations, 0.1 and 1 mg/l. Revealing the effects of AgNPs on the expression of MADS-box genes will increase our knowledge of their role before implementing a large-scale agricultural utilization of AgNPs in the improvement of plant growth and development.

The harvest season of apricots is short and fruit cannot be protected in cold stores for a long time. For those reasons, apricot production and consumption are lower than in other fruit species. This study was conducted for the purpose of breeding new late ripening apricot varieties. To this aim, a total of 3718 hybrid genotypes of apricots were obtained from 42 crosses. Phenological, pomological and yield analyses were performed and variations of fruit development period, fruit size, polarimetric dry matter (Brix), total acidity, yield and other traits were determined. Two years of results for important traits are given for 12 promising genotypes. Fruit development period varied between 148 and 167 days, fruit weight 25.2 and 41.2 g, Brix 16.3 and 22.6% and total acidity 0.56 and 1.25%.

An experimental population commonly used in genetic analyses of gene or quantitative trait loci (QTLs) in rice is chromosome segment substitution lines (CSSLs). In the present study, with the typical indica variety Guangluai 4 as a donor and japonica variety Taichung 65 as a recipient, seven CSSLs carrying F₁ pollen sterility genes S-b, S-d, S-e, S-b/S-d, S-b/S-e, S-d/S-e, and S-b/S-d/S-e were obtained by specific selection for the target genes, non-specific selection for the genome of the recurrent parents in four backcross populations (BC₁F₂, BC₂F₂, BC₃F₂ and BC₃F₃). We evaluated the genetic effect of the F₁ pollen sterility genes using 35 F₁ hybrid individuals in crosses derived from CSSLs and Taichung 65. Pollen fertility of F₁ hybrid plants was observed and the results indicated that the single genes S-b, S-d and S-e can cause 67.7%, 14.6% and 53.2% of pollen sterility, respectively. Multiple genes S-b/S-d, S-b/S-e, S-d/S-e, and S-b/S-d/S-e can cause 76.6%, 85%, 68.7%, and 93% of pollen sterility, respectively.

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.

The Lancelot variety is a late to semi-late six-row feeding winter barley. It was developed at the Breeding Station, Lužany, SELGEN a.s. and registered in the Czech Republic in 2013. Lancelot has very good resistance to winter stresses in combination with resistance to BaMMV/BaYMV (Barley mild mosaic virus/Barley yellow mosaic virus) based on the gene rym4.

One of the aims in red clover (Trifolium pratense) breeding is to increase the polyphenol oxidase (PPO) activity, which may effectively reduce protein breakdown in silage and when cattle are fed by fresh clover. We analysed total PPO activity spectrophotometrically and on the level of gene expression using real-time quantitative PCR in single plants derived from an interspecific T. pratense × T. medium hybrid. Experiments were performed for two years and evaluated according to the general linear model with three factors (family, year, and cut). The analysis revealed considerable variability in total PPO activity between individuals and between families. Four families and two individuals with significantly higher PPO activity were selected. Their PPO activity ranged from 3.411 to 3.547 mkatal/min/g and from 4.041 to 5.731 mkatal/min/g, respectively, in comparison with the control variety Amos (2.370 mkatal/min/g). The majority of PPO transcripts were expressed by the two genes PPO1/5 and PPO2. In some genotypes, the PPO5 gene was expressed. Quantitative PCR confirmed the highest activity of PPO genes in seven hybrid plants with higher DNA contents corresponding to 30 chromosomes with 815 013 copies per plant. Our results indicate the suitability of combining two methods for improved selection: initial expression analysis to assess the PPO transcript level indicating gene activity and subsequent enzymatic assay.

Evaluation of genetic effects in cotton (Gossypium hirsutum L.) high fibre strength lines is necessary for the genetic improvement of fibre properties. Six breeding lines with high fibre strength and five transgenic Bt cultivars were diallely crossed. Fibre properties and agronomic traits of 11 parents and resultant 30 F₁ hybrids were analyzed by an additive-dominant model with genotype by environment interaction effects. Lint percentage, seed index, fibre length, strength and micronaire were primarily controlled by additive effects. Lint yield was mainly governed by dominance effects. Boll size was equally influenced by additive and dominance effects. A9-1 was a desirable general combiner for lint percentage, micronaire and fibre length. Yumian1 and Jinxing2 were good general combiners for fibre strength. Gk22 was a desirable general combiner for lint yield and boll size but poor for fibre length and strength. Some F₁ hybrids were identified with favourable heterozygous dominant effects for lint yield and various fibre properties. This study revealed that current transgenic Bt cotton cultivars can be improved in fibre quality and lint yield by using some of the lines with high fibre strength in crosses with them.

Plant lectins have become efficient sources of insect resistance in crops. The present study was conducted to identify, amplify, clone and characterize the plant lectin gene GNA. The lectin, present in Galanthus nivalis (snowdrop), is an agglutinin toxic to hemiptera. The attempt was made to elucidate the relationship of the lectin gene trGNA (GNA isolated and characterized from Turkey) with other previously cloned lectins having insecticidal activity and to ensure the presence of the conserved mannose-binding region/site in the gene sequence. The full-length cDNA of trGNA was 477 bp that contained a 333 bp open reading frame encoding 157 amino acid proteins with 23 amino acids of signal peptide. BLAST results showed that trGNA has 89-97% similarity with previously reported GNA sequences while it has 84-96% similarity with earlier reported GNA protein sequences. No intron was detected within the region of genomic sequence corresponding to trGNA full-length cDNA. According to the search results from the NCBI (National Centrer for Biotechnology Information database), trGNA from Galanthus nivalis is most similar to the previously reported lectin sequences of Narcissus tazetta with a similarity percentage of 87%. The obtained results are useful for engineering of plants with enhanced insecticidal activity against chewing and sucking insects, causing crop pests. In addition, medical application of lectins may also be considered.

Spirodela polyrhiza belongs to the family Lemnaceae (duckweed), which is a group of small aquatic plants offering an attractive plant expression system for the production of recombinant protein. No frond regeneration protocol has been established in this species yet. An efficient protocol for plant regeneration through organogenesis has been developed in Spirodela polyrhiza for the first time. Calli were successfully induced from 92% of explants on Murashige and Skoog (MS) medium with 10 μM naphthaleneacetic acid, 2 μM thidiazuron, 1μM 2,4-dichlorophenoxyacetic acid (2,4-D) and 3% sucrose. MS medium containing 1% (m/v) sorbitol and 1 µM 2,4-D supported long lasting growth (at least 5 months) of 98% of calli. Plants regenerated from 92% of calli on Schenk and Hildebrandt (SH) medium with 10 μM zeatin and 1% (m/v) sucrose. The protocol for frond regeneration could be a good basis for transgenic engineering of S. polyrhiza.

The Antisense 4CL gene was transfected into alfalfa through Agrobacterium-mediated transfer. The test results indicated that the antisense 4CL gene was successfully integrated into the genome DNA of alfalfa and was stably transmitted to the offspring. Compared to the wild-type plants, the lignin content of T₀ and T₁ generation plants was reduced by 45.77% and 31.97%, respectively; there were no significant differences in height and weight of T₀ and T₁ plants, compared to the wild-type plants. However, the transgenic plant differed from the wild-type plant by softer stems and leaves, larger leaves, fewer flowers and a fewer seeds. The T₀ line was susceptible to disease infection, but significantly improved in the second year. The results suggest that the 4CL gene from Amorpha fruticosa can be used to regulate lignin biosynthesis in transgenic forage crops.

Fire blight is one of the most destructive diseases of pome fruits, especially pears. In current conditions when the demand for organic products is increasing, improvement of resistant rootstock and varieties is becoming important due to the lack of an effective disease management method against fire blight caused by Erwinia amy-lovora as well as the harmful effects of chemicals on environment, human and animal health. The findings of the researchers as to which variety performs well in terms of the transmission of fire blight resistance are quite important for new breeding programs. In the study, three varieties with high commercial value (Magness, Santa Maria and Williams) were identified as the maternal parents and 21 hybridization combinations were made with seven varieties (Akça, Ankara, Conference, Güz, Kaiser Alexandre, Kieffer and Taş) as pollinators. The Magness maternal parent was found superior when compared with the other maternal parents for the variety susceptibility level to fire blight. Apart from the differences in the susceptibility level of 21 different combinations of hybrids to fire blight, the commercially superior ten hybrids (I-15-24, II-13-1, II-13-19, II-13-34, II-13-73, II-27-21, II-27-55, II -32-44, III-22-638, III-27-590) have been determined via the weighted ranking method from the parameters of disease resistance and different fruit characteristics measuring the commercial preference of the fruits such as fruit quality, attractiveness, size, firmness and rustiness

The present paper summarized some knowledge of modern technologies, applied in apple (Malus domestica) genome studies. New generation sequencing allowed single nucleotide polymorphism (SNP) chip technologies for genotyping, description of functional apple genes, characterization of the evolutionary results in apple genome fragment transition, as well as phylogenetic reconstruction of the genus Malus, being the confirmed progeny of M. sieviersii. Based on these technologies, newly developed putative markers may give the most important biological data such as age, geographical origins, tissue type determination, and external visible characters. The new generation genotyping platforms, representing very high efficiency, are now successfully applied for random apple genome-wide association (GWA) studies as well pedigree-based analysis and marker-assisted selection (MAS).

Ruzrok, the first sorghum cultivar of Czech provenance, was selected as a multiline cultivar from sorghum collected in the Bílé Karpaty region in Moravia, Czech Republic. In the present paper, basic plant morphological and yield-related characteristics as well as characteristics related to plant resistance to major abiotic and biotic stress factors are described. The major advantages of Ruzrok consists in its earliness, plant height and high growth rate of plants leading to high biomass production. Ruzrok was registered for its high biomass yield; however, its grains can also be used for flour production and food purposes after the technological removal of tannin-rich outer layers of grains. Recommendations for basic cultural practices such as sowing date, fertilization and protection against pests and diseases are given. In conclusion, potential utilization of the novel sorghum variety as both biomass and fodder crop is discussed.

Wheat, one of the world's major crops, is seriously affected by fungal diseases, especially in regions with high moisture and moderately warm temperatures. This paper reviews various molecular and conventional techniques that are used to identify genotypes with resistance alleles associated with Fusarium head blight (FHB) diseases. Quantitative trait loci (QTL) type II, designated as Fhb1, are frequently applied in plant breeding, and the newly recognized genes related to resistance to this fungal disease give extra insights into marker-assisted selection (MAS). Molecular markers are robust tools that may be routinely used in MAS for the mapping of resistance genes in crop breeding. FHB resistance is polygenic, and different resistance genes could be conveyed into a single genotype by MAS, which might ensure greater resistance to FHB disease. In conclusion, different researchers have used various techniques to control FHB resistance, such as MAS, gene pyramiding (through backcross), and molecular markers (association with resistance QTLs or genes).

Ornamental sunflowers are widely cultivated for use as cut flowers and/or as garden plants. The objective of the study was to investigate breeding values of new F₁ ornamental sunflower hybrids using incomplete diallel crossing of four ornamental inbred lines: Heliopa, Talia, Iskra and Neoplanta. Six traits important for ornamental market use were studied. Additive gene effects prevailed in most tested traits except for lateral floral diameter and duration of lateral flowering, which exhibited non-additive effects. The results indicated that the Talia × Neoplanta hybrid combination was the most promising for cut flowers due to long and strong branches, relatively big lateral flowers while Heliopa × Iskra and Heliopa × Talia hybrids were suitable for use as garden plants due to strong plant habit, long flowering time and desirable plant height. The results obtained from this study will be helpful for further ornamental sunflower breeding.

In the past decade, next-generation sequencing (NGS) platforms have changed the impact of sequencing on our knowledge of crop genomes and gene regulation. These techniques are today acquiring a great potential in metagenomic and agrigenomic research while showing prospects for their utilization in plant breeding. We can now obtain new and beneficial information about gene regulation on the cellular as well as whole-plant level through RNA-sequencing and subsequent expression analyses of genes participating in plant defence reactions to pathogens and in abiotic stress tolerance. NGS has facilitated the development of methods to genotype very large numbers of single-nucleotide polymorphisms. Genotyping- by-sequencing and whole-genome resequencing can lead to the development of molecular markers suited to studies of genetic relationships among breeding materials, creation of detailed genetic mapping of targeted genes and genome-wide association studies. Plant genotyping can benefit plant breeding through selection of individuals resistant to climatic stress and to pathogens causing substantial losses in agriculture.

The diversity of three non-coding plastid DNA loci (trnL/trnF spacer, trnV/16SrRNA spacer, trnL/trnL intron) was assessed in 16 Solanum L. species (135 individuals). Polymorphisms were detected by denaturing gradient gel electrophoresis (DGGE) and verified by direct sequencing. No intraspecific diversity and only poor interspecific diversity was detected. Unique S. mochiquense Ochoa specific length polymorphism at the trnL/trnL locus represented by duplication of an 18 bp segment was discovered. The detected DGGE interspecific trnL/trnF locus polymorphism did not specifically associate with single point mutations in the sequence confirmed by sequencing. The DGGE method was found to be a simple and cheap pre-exploring tool for mutation detection in compared DNA regions. Some identified polymorphisms can be used in the management of genetic resources.

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 aim of this study was to verify the high resolution melting (HRM) method in the analysis of single nucleotide polymorphism (SNP) and simple sequence repeat (SSR) markers in pea (Pisum sativum L.). A recombinant inbred line population, Carneval × MP1401, was tested for three SNP and 103 SSR markers. HRM analysis was conducted on a LightScanner 96 instrument with LC Green dye. The melting curve shape permitted two polymorphic genotypes to be distinguished. The results were confirmed by gel electrophoresis. Three SSR markers were sequenced and analysed by the melting prediction software. The results confirmed the presence of one polymerase chain reaction (PCR) product with two melting domains. Sequence tagged site (STS) markers produced specific products: Psat_EST_00189_01_1 (300 bp), Pis_GEN_18_2_1 (400 bp), Pis_GEN_7_1-2_1 (600 bp). Amplicons contained one, four and seven single nucleotide polymorphisms, respectively. Melting curve differences enabled the population genotyping except for Psat_EST_00189_01_1 where resolution was too low. Primers for Psat_EST_00189_01_1 were redesigned to obtain a shorter (100 bp) PCR product which increased the resolution. The number of SNPs and amplicon length are crucial for HRM resolution. The HRM method is fast and has a high throughput. The melting analysis of 96 samples takes less than 10 min. Agarose gel analysis confirmed the reliability of HRM, which eliminates laborious post-PCR analysis.

The flowering onset of 19 apple progeny was evaluated in 2005-2014 on a total number of 715 seedlings in comparison with their parents and grandparents. A very low flower set delays generally the onset of flowering by one day in comparison with a higher flower set. The maximum span between the first flowering onset and the last one within all the progeny of the study was 11 days. With one exception, the incidence of the first flowering dates of all the progeny fluctuated only within four days - April 28 and May 1. Among them, the great majority of the seedlings had the first flowering date span of not more than ± one day. The progeny of Pink Lady × Discovery was the most exceptional having the mean day on the April 17 and the span about two days longer. The means of the first flowering dates within seedling populations and corresponding dates of both their parents and grandparents were very highly correlated (r = 0.926 for parents and r = 0.877 for grandparents). The incidence of flowering onset dates in almost all progeny followed a typical Gaussian distribution, in which the majority of seedlings start flowering within 3 or 4 days. The maximum difference between both extremes (found only in one progeny) was 11 days. The share of seedlings in both extremes was, however, very small - less than 2%.

Five winter wheat cultivars, differing in resistance to Septoria tritici blotch (STB), were spray inoculated under field conditions for two years and at two locations with nine Mycosphaerella graminicola isolates and a mixture of isolates that were obtained from different regions of the Czech Republic. Main aims of this study were (i) to compare isolate, host cultivar and environmental effects on five traits indicative of STB severity and (ii) to analyse pathogen aggressiveness and host-pathogen relations for improving evaluation of cultivar resistance. ANOVA showed in all traits, except the reduction in 1000 grain weight, significant isolate effects. However, the effects of isolate and genotype by isolate interactions were much lower (2.3-4%) than cultivar (19.1-53.7%) and environmental (11.9-58.6%) effects. Cultivar resistance to the disease limited much the loss in grain weight per spike to a halve, from 34.7% in the susceptible Bakfis to 17.3% in the resistant Arina. Visual scoring of symptoms in the middle and at the end of disease development (performed on the 1-9 scale), reflecting the disease progress and infected leaf area, showed the highest cultivar effect (54%) and could be recommended for evaluation of cultivar resistance in breeding practice. All examined traits were significantly interrelated, but significant differences between all the five cultivars were only detected after examination of the % coverage of flag leaves with lesions bearing pycnidia. Resistance in the cultivar Arina was detected by all isolates and the isolate mixture. In spite of significant differences in classification of resistances in the cultivars Bohemia and Mulan after inoculation with one isolate (1081), specific interactions between cultivars and isolates collected in this Central European region are rare. The study leads to a conclusion that investigation into stability of STB resistance across a wide range of environments is more valuable for breeding purposes than the study of cultivar response to different isolates. Combination of important isolate properties in a mixture of isolates is stressed as well.

The scientific report presents results of our studies on the gene Pch1, conferring resistance to eyespot disease in wheat, caused by the fungus Occulimacula spp. The presence of the gene Pch1 in wheat cultivars was analysed using the molecular marker Xorw1. In total 106 wheat cultivars registered in the Czech Republic and 54 breeding lines were tested. The gene Pch1 was found in the cultivars Annie, Beduin, Hermann, Iridium, Manager and Princeps and in three breeding lines. Some of these cultivars were tested for eyespot resistance in field trials and showed a high level of resistance. Cv. Hermann was the most resistant winter wheat cultivar in our experiments in the last two years. The method of artificial infection by Oculimacula spp. was optimized.

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.

Doubled haploidy breeding protocols have revolutionized the varietal development programmes in bread wheat, however, the protocols have not proved much efficient in durum wheat. Presently, the durum wheat × maize system is being widely followed for haploid induction but the frequency of haploid development is very poor which has limited its application in durum wheat improvement programmes. In order to formulate an efficient wide hybridization-mediated approach for haploid induction in durum wheat, different genotypes of durum wheat were subjected to hybridization with Imperata cylindrica, a wild perennial grass for the first time in this laboratory. The investigation was carried out for two seasons. During the 1^st year, the investigation was carried out on one genotype only, Langdon, in order to notice the development of haploid embryos and the factors that influence the haploid induction frequency. The most important factor influencing the embryo formation frequency was found to be the concentration of 2,4-dichlorophenoxyacetic acid (2,4-D). Upon pollinating the emasculated spikes of durum wheat genotypes, various concentrations of 2,4-D were injected into the uppermost internode of wheat culm for three consecutive days after pollination to find out the most responding concentration for haploid induction. During the next year, the protocol was applied to eight durum wheat genotypes. The frequency of haploid induction parameters varied with the durum wheat genotypes as well as 2,4-D concentration used. The mean pseudoseed and embryo formation frequency over all the genotypes ranged from 30.2 to 56.3% and 1.2 to 18.4%, respectively. The average embryo formation frequency over all the genotypes was found to be highest (18.4%) at 250 mg/l 2,4-D whereas it was superior for the genotypes WH 896 and Langdon over all the 2,4-D concentrations. At the most responding 2,4-D concentration (250 mg/l), the genotype A-9-30-1 exhibited the highest embryo formation frequency (32.1%). The ploidy status of the developed embryos was identified using cytological analysis carried out on the rootlets of the tissue culture generated plantlets.

The wheat stem rust pathogen, Puccinia graminis f.sp. tritici, is a significant and devastating disease of wheat crops worldwide. Wheat has many wild relatives in which to source new resistance genes, including the cereal crop of rye in the tertiary genepool. The aim of this study was to assess the reaction of 1BL.1RS and 2RL.2BS double wheat-rye translocation lines to virulent stem rust races from Africa and North America. BC₁F₃ and BC₁F₄ populations from a cross between the line KR99-139 (a double wheat-rye translocation line with 1BL.1RS and 2RL.2BS) and the bread wheat cultivar Topper were used in the study. Several of the populations homozygous for 1BL.1RS and heterozygous for 2RL.2BS showed resistance and low severity adult plant resistance (20RMR-50MSS) to the African stem rust race TTKSK in the field. None of the tested populations with varying chromosome combinations showed seedling resistance to any of the tested stem rust races. Thus, these resistant populations likely carry gene/s effective at the adult plant stage since all stage resistance genes with major effect appear to be absent based on the seedling assays. Resistant lines combined three chromosomes (1RS, 2RS and 2BS) which make their direct use in breeding more complicated. Mapping studies followed by potential transfer of genes between 2R and 2B will make the identified minor genes more useful in wheat breeding.

As an important antioxidant for plants and humans, L-ascorbic acid (AsA, vitamin C) can scavenge reactive oxygen species (ROS) and can be regenerated from its oxidized form in a reaction catalyzed by dehydroascorbate reductase (DHAR). To analyse the effect of overexpressing DHAR on tomato (Solanum lycopersicum), an expression vector containing potato cytosolic DHAR (DHAR1) or chloroplastic DHAR (DHAR2) cDNA driven by a cauliflower mosaic virus 35S promoter was transferred into tomato plants. Compared with the wild type (WT), DHAR1 overexpression increased DHAR activity and AsA content in both leaves and fruits, while DHAR2 overexpression increased DHAR activity and AsA content mainly in leaves. DHAR1 and DHAR2 overexpression increased the chlorophyll content and photosynthetic rate of transgenic lines, but had no effect on plant height and stem diameter. Furthermore, the germination rate, plant fresh weight, seedling length and chlorophyll content of transgenic DHAR1 and DHAR2 plants under salt stress were higher than those of WT plants. In addition, the transgenic plants also exhibited considerable tolerance to oxidative damage induced by methyl viologen (MV). Taken together, these results indicated that overexpressing potato DHAR1 and DHAR2 enhanced the level of AsA in tomato and, consequently, increased the tolerance of tomato to salt and MV stress.

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.

Meadow grassland communities were monitored in situ in the region around the town of Bansk᠂ystrica (Central Slovakia) over the 2008 growing season. The botanical compositions were determined at the sites listed in NATURA 2000 (Donovaly, Tajov, and Priechod). The respective site coordinates were determined using a Global Position System, and then put on the digital map of the Google server. A range of rare, endangered, and protected plant species were found at the monitored sites (e.g. Gymnadenia densiflora, Lilium bulbiferum, Lilium matragon, and Stipa joannis).

By 2008, twelve localities had been investigated. At each location we assessed the degree of threats to the wild grapevine. Flowering plants were seldom found. The plants found were localized geographically, and 149 vines were described using the characteristics of shoot types and leaves, using the O.I.V. descriptor list. Morphological differences of the leaf shape, hair or bristle density are high. A few seeds which were found in dry black berries are much smaller in size than the seeds of Vitis vinifera ssp. sativa. From plants that were easily attainable, cuttings were taken with the objective to multiply the Vitis sylvestris and to establish an ex situ collection. In 2008, we repeated the procedure with 54 vines. The state of health of the vines in situ is very good. No fungal diseases were visible, and mites occurred only rarely. In the nursery, some plants were contaminated by mildew.

Introgression lines derived from Oryza minuta and O. sativa subsp. japonica var. Junambyeo were crossed for a mapping of the population composed of 112 recombinant lines to identify putative QTLs against rice blast disease using the percentage of diseased leaf area. By using 148 Sequence Tagged Site (STS) and Single Sequence Repeat (SSR) markers, five QTLs on chromosomes 6, 7, 9 and 11 and seven epistatic QTLs were identified against two blast isolates (KI307 and KI209). Of them two QTLs (qKI307-2 and qKI209-3) shared a similar position on chromosome 11. O. minuta introgression contributed the resistance allele for all of these QTLs. Combined phenotypic variations by QTL and (E-QTL) accounted for 56.9% against KI307, and 53.4% against KI209. Each QTL could account for the resistance variation between 11 and 24.6%. The resistance from wild introgressions was attributable to a combination of QTLs and epistatic effects between different loci, capable of inducing hypersensitive reactions. Our findings are in support of the strategy of pyramiding major QTLs to develop improved rice varieties with durable broad spectrum resistance against the blast fungus.