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High-throughput molecular technology DArTseq generates markers for potential use in molecular breeding of crops. Using DArTseq, we analysed a comprehensive set of 333 European potato varieties reflecting the outcomes of long-term breeding history and representing a potential germplasm for future breeding of potatoes in the Central European region. The varieties were classified according to four factors: region of origin, breeder, earliness and utilisation mode, that may potentially reflect their genetic structure, and for which complete data were publicly available. The DArTseq analysis was performed by the service centre, the Diversity Array Technology (University of Canberra), which generated approximately 38 000 silicoDArT and 64 000 SNP (single nucleotide polymorphism) polymorphic markers. The discriminatory ability of the markers in relation to the factors was confirmed using neighbour-joining and principal coordinate analysis (PCoA), while the informativeness was assessed using the discriminant analysis of principal components (DAPC). The analyses identified the 50 SNPs most strongly associated with each factor, along with their highly probable chromosomal localisation. Herein presented research contributes to the evaluation of potato genetic resources by adding the novel molecular data of active germplasm and implies their future utilisation in genome wide association studies and marker assisted selection.

The need of vernalisation, controlled by the gene VRN-1, impacts wheat adaptation and yield stability, yet field evidence on the plasticity of VRN-1 homoeologs expression is limited. We quantified VRN-1 homoeolog dynamics across two sites and two seasons in seven cultivars, by sampling their apex and leaf. VRN-A1 varied with genotype (P < 0.001***), tissue (apex > leaf; P < 0.001***), apex development (P < 0.001***), day length (P < 0.001***), and to a lesser extent, on short-term freezing exposure, quantified as a 5-day freezing-degree sum (FDS; P = 0.019*). Photoperiod class (Ppd-D1a vs Ppd-D1b) added an additional effect (P = 0.001***). VRN-B1 showed strong genotype effects (P < 0.001***), a modest effect of site on its expression (P = 0.025*), and pronounced associations with microclimate variables (day length, thermal sums, freezing exposure; all P < 0.001***). Directionally, Ppd-D1a backgrounds tended to advance the development while showing earlier apex VRN-A1 peaks. Overall, VRN-A1 expression mainly reflected developmental stage and seasonal forcing, whereas VRN-B1 might be more microclimate-responsive, indicating complementary roles for timing and stress-response plasticity. To isolate causal effects and to further explain these dynamics, targeted sequencing and tests in near-isogenic lines will be needed in future work.

Transgenic organisms modified with ancestral genes for nitrogen metabolism are rare. Previously, it was reported that genetically modified Nicotiana tabacum with the ARO4 gene of aromatic amino acid synthesis from the yeast Debaryomyces hansenii increases its growth during moderate salt stress. In this investigation, it was explored if the changes in the expression of the gene DhARO4 in Nicotiana tabacum, during saline irrigation, are related to the chlorophyll content and the total reactive oxygen species production. Seedlings of transgenic and wild type Nicotiana tabacum germinated in standard conditions were divided into two irrigation groups, with 100 mM of NaCl and with tap water; and, after 50 days, in the non-senescent adult leaves of the plants, the total chlorophyll a and b and the total chlorophyll content were determined by spectrophotometry and the reactive oxygen species production (•OH, ¹O₂, H₂O₂) was quantified by a 2',7'-dichlorodihydrofluorescein assay. The expression of the DhARO4 gene was verified with a salt shock of 100 mM of NaCl for 24 hours in the transgenic and wild type plants in the tap water irrigation group. The DhARO4 gene transcript increased (P < 0.05) in the transgenic plant; meanwhile, the average concentration of chlorophyll a increased (P < 0.05), and the average production of reactive oxygen species decreased (P < 0.05).

Sorghum as a C₄ crop has been shown to be both drought tolerant and photosynthetically productive. In this study, we demonstrated that sorghum SbSnRK1βγ2 (SbSNF4-2), the γ subunit of the sucrose non-fermenting 1 (SNF1)/SNF1-related protein kinase 1 (SnRK1) heterotrimeric complex, increased the plant height and biomass in Setaria viridis, a C4 relative of sorghum, but not in rice, a C3 relative, when overexpressed driven by the maize ubiquitin promoter. However, the overexpression did not increase the tiller number in S. viridis, although it caused modest increases in the tiller number in both sorghum and rice. In addition, SbSnRK1βγ2 did not affect the panicle weight in sorghum, but its overexpression doubled the panicle weight in S. viridis in all four evaluated transgenic lines. Overall, the overexpression of SbSnRK1βγ2 tripled the biomass production in S. viridis, indicating SbSnRK1βγ2’s potential in any future cellulosic biofuel production and S. viridis’ utility as an alternative genetic vehicle to functionally characterise sorghum genes.

The present study was to determine the genotypic and environmental variability and stability in seed yield, oil content, oil yield, oleic and linoleic acid of 10 safflower lines derived from a cross of Dinçer 5-18-1 × Montola 2000 together with six cultivars under six environments at five locations. The effects of genotypes, environments and genotype × environment interactions were highly significant (P < 0.01) for seed yield and oil content. Averaged across all environments, the seed yield was lowest in the cultivar Olas (2 352 kg/ha), and highest in the line Bay-Er 5 (2 869 kg/ha). According to mean (x_i) and regression coefficient (b_i) values, the Bay-Er 16 was better adapted to unfavourable environmental conditions, whereas the Bay-Er 1, Bay-Er 5 and Bay-Er 14 were better adapted to favourable environmental conditions. The highest oil content across environments, over 35%, was recorded in the line Bay-Er 15 and the cultivars Olas and Linas. The best adaptability to the environments was observed in the cultivar Olas. The oleic acid content of genotypes increased and the linoleic acid contents decreased from the north to the south latitudes. The oil content of genotypes grown in Southeastern Anatolia was higher than in the other regions. Within the regions, seed yield and oil content was higher after autumn sowing than after spring sowing.

Citrus sinensis (L.) Osbeck (sweet orange) is the most important cultivated citrus fruit in the world. However, Hanglongbing (HLB) disease, caused by Candidatus Liberibactor asiaticus (CLAs), poses a major threat to sweet orange production, by hindering colour, quality and export. Carotenoid cleavage oxygenases (CCOs), which include carotenoid cleavage dioxygenases (CCDs) and 9-cis-epoxycarotenoid dioxygenases (NCEDs), are essential for plant growth, development, and adaptation to phytohormonal, biotic, and abiotic stresses. This study identified 14 CsCCO genes in C. sinensis. Structural and conservation studies were conducted using gene structure and conserved domain analysis. Genomic localisation, gene duplication, and similarity among these genes were also examined. Gene ontology analysis predicted that CsCCOs could be involved in the carotene catabolic process. Analysis of cis-regulatory elements revealed that most CsCCO genes are involved in responses to stress, light signalling, and plant growth regulation. Genes in the 9-cis-epoxycarotenoid dioxygenase (NCED) subgroup are predominantly localised in chloroplasts, whereas genes in other subgroups are primarily found in the cytoplasm. All 13 of the CsCCOs genes identified were regulated by 25 microRNAs, indicating the crucial role of microRNAs in gene regulation in Citrus sinensis. The expression patterns of CsCCO genes in response to biotic and abiotic stress were studied. Transcriptome analysis demonstrated that CsNCED3 and CsNCED10 were up-regulated in response to HLB. This provides insight into the function of CCO genes in C. sinensis and identifies potential candidate genes for combating citrus greening.

Despite all the complications that arise with root research, such as slow, laborious, and unclear genetics, roots are a promising object of interest for breeders because many root traits are compatible with high yield potential. It is a great challenge for further research that there is a wide demand for information on the “hidden half of plant metabolism” from many research fields. We have summarized the main obstacles in root system research and sketched a solution for breeding in field conditions so that the result was more meaningful to the farmer. (i) The most important challenge in root research is linking the functional identification of root system properties with the aboveground parts. (ii) Field breeding is irreplaceable, and methods allowing the evaluation of roots under field conditions are indispensable. (iii) Low heritability of root system trait discourages breeders. However, root properties show broad genotypic variability, allowing the efficient use of these traits as selection criteria. (iv) The root traits are variable, and many fluctuate under the influence of environmental factors, which complicates efforts to define ideotypes and explains the different conclusions obtained by researchers from different environments. The breeding programs targeting the root system are sporadic even in a global context. This is a great reserve for breeding progress in the era of climate change, water scarcity, a possible shift to extensive farming systems, and in the era of environmental programs.

Genetic diversity is referred to as any variation at the phenotypic, DNA or genomic level of an individual, population or species. The appraisal of diversity is important to understand its pattern and evolutionary relationships between germplasms or genotypes, which will aid in sampling the genetic resources in a more systematic manner for conservation and crop improvement. The present study employed 50 simple sequence repeat (SSR) markers linked to the yield and fibre quality/colour traits for estimating the genetic diversity in 33 cotton genotypes of diploid and tetraploid species differing in fibre colour. The diversity analysis was performed in GenAlEx (Ver. 6.41) and Powermarker (Ver. 3.25) while DARwin (Ver. 6.0.21) software was used to establish the phylogenetic relationships following neighbour-joining (NJ) and unweighted pair group method with arithmetic (UPGMA) mean method. Markers generated 186 polymorphic loci as genotypic data with an average of 3.72 alleles and an average polymorphic information content (PIC) value of 0.59 per SSR locus. The NJ and UPGMA grouped 33 genotypes into three major clusters I, II and III consisting of 21 tetraploid Gossypium hirsutum, 10 G. arboreum coloured and 2 white cotton genotypes, respectively. In the PCA, the first two components (PC1 and PC2) explained 74.69% of the variation and the biplot plotted the 33 genotypes in three groups. The study established the diverse nature of 33 cotton genotypes based on their fibre colour and ploidy level. With confirmation of the prevalent genetic diversity, we suggest that hybridisation can be planned among diverse genotypes to unleash greater variation in the fibre colour or to derive superior cross combinations.

Powdery mildew (PM) is a fungus that causes disease in both the field and the greenhouse. Utilizing resistant cultivars is the most effective approach of disease management. To develop insertion-deletion (InDel) markers associated to this trait, the whole genomes of the PM resistant line M17050 (P1) and the PM-susceptible line 28-1-1 (P2) were sequenced. A total of 1 200 InDels, with an average of 100 markers per chromosome, were arbitrarily chosen from the sequencing data for experimental validation. One hundred InDel markers were ultimately selected due to their informative genetic bands. Further, an F₂ segregating population of melons generated from these two parents was inoculated by the PM pathogen. Based on bulk segregant analysis (BSA) using these 100 InDel markers, the powdery mildew resistance was associated with the genomic region LVpm12.1 on the melon chromosome 12. This region overlapped the previously described quantitative trait locus (QTL)-hotspot area carrying multiple PM-resistance QTLs. Moreover, conventional QTL mapping analysis was done, which located LVpm12.1 in the region between 22.72 and 23.34 Mb, where three highly polymorphic InDel markers MInDel89, MInDel92, and MInDel93 were detected. Therefore, these markers could be used to track this resistance locus in melon while the lines carrying this locus could be employed in PM melon resistance breeding programs after validation tests.

Yellow rust (YR), caused by Puccinia striiformis f.sp. tritici (Pst), is a global threat to wheat production. In this study the response of 46 wheat and triticale cultivars to Pst at the adult plant stage (APS) was evaluated during two successive growing seasons at Sulaimania, Iraq. Also, we used a molecular analysis to find the yellow rust resistance (Yr) genes present in the individual cultivars. The results revealed large differences in the response to Pst between the cultivars. Most of the cultivars were susceptible to YR; the mean coefficients of infection (CI) varied from 0.23 in cv. Sarah to 83.33 in Hsad. High resistance levels were found in Al-Wand, Kalar 1, Rezan, and Sarahat APS, while Al-Rashid, Charmo, Faris 1, Maaroof, Rabiea, and Iratom displayed moderate resistance. The level of Yellow rust infection was higher in 2023 than in 2022 in most tested cultivars. Molecular analysis revealed the highest number of Yr genes (Yr2, Yr5, Yr7, Yr9, Yrvav, Yr15, Yr24, Yr26, and Yr32) in the cv. Al-Wand, followed by Sulaimani 2 with eight Yr genes (Yr2, Yr5, Yr7, Yr9, Yr15, Yr24, Yr26, and Yr32). Only one Yr gene was found in Iratom and Tamuz 3. Yr2 was the most frequently identified gene, present in the majority of tested cultivars (87%), followed by Yr7 (76%) and Yr9 (74%), respectively.

Sustainable global wheat production requires wheat varieties, that are sufficiently resistant to the main wheat diseases. The economically important fungal pathogens worldwide include powdery mildew (PM), yellow rust (YR), leaf rust (LR) and blotch causing pathogens including Septoria nodorum blotch (SNB) and Septoria tritici blotch (STB). Here, we present the evaluation of winter wheat varieties of diverse origin against the prevalent local populations of PM, YR, LR, STB and SNB under natural infection conditions through image-based phenotyping in two consecutive years (2019 and 2020). We found several varieties to be resistant against multiple diseases. Following the association mapping, we obtained a total of 206 marker trait associations for all the parameters scored which were condensed to 79 quantitative trait loci (QTLs) (eight QTLs for PM, 25 QTLs for LR, 11 QTLs for YR, 19 QTLs for SNB and eight QTLs for STB) based on the linkage disequilibrium among the molecular markers. The known genes present at these QTLs are discussed in detail. The varieties resistant to multiple diseases, identified with the QTLs and molecular markers can be considered as elite raw material for future wheat breeding.

Knowledge of gene actions governing begomovirus resistance and plant architectural traits is a prerequisite for a successful hybrid breeding programme. Therefore, the gene actions associated with these traits were studied in two intervarietal crosses of Cucurbita moschata (C₁: Punjab Nawab × MVSR-6711 and C₂: Punjab Nawab × P-135). We used the generation mean analysis of six generations for this purpose. Significant differences between the generation means were observed for all the traits in both crosses. The parental lines differed significantly in most of the studied traits. The nature and magnitude of the gene effects of seventeen traits varied by trait and cross. A simple additive dominance model was adequate for the internode number, leaf length and width, petiole length, fruit weight and cavity diameter in C₁ and the number of fruits/plant in C₂. The non-allelic interaction was found to be significant for a majority of the traits including the per cent disease index of the squash leaf curl China virus, tomato leaf curl New Delhi virus and their mixed infections, which indicated, that recurrent selection in biparental progeny might be useful for the accumulation of genes with additive effects. Duplicate epistasis was observed for the vine, internodal and peduncle length in C₁ and the internode number, petiole and peduncle length, peduncle and fruit polar diameter in C₂. This information will help to establish a breeding program for the simultaneous improvement of virus resistance and yield traits in pumpkins.

The present study was conducted to explore the variability generated through recombination breeding for nine economically important traits in Indian mustard (Brassica juncea L. Czern & Coss.). Delineation of the inbred lines to different gene pools, based on genetic diversity, enables their utilisation in hybrid breeding. The unweighted pair group method with arithmetic mean (UPGMA) and a Euclidean distance matrix was used to delineate the inbred lines to clusters. The variability was studied using the range and coefficients of variation of the traits. Significant variability was observed for all studied traits except for oil content and days to maturity. 128 Indian mustard genotypes were grouped into four distinct gene pools based on genetic diversity. A set of 20 most diverse genotype combinations was produced. Promising inbred lines were identified and recommended as donors for the respective trait. The pedigree analysis of the inbred line groups revealed, that recombination breeding caused a large diversity as confirmed by the assignment of inbred lines with the same parentage to specific clusters.

The objective of this study was to investigate the diversity of 59 accessions of barley using inter simple sequence repeat (ISSR), conserved DNA-derived polymorphism (CDDP), and start codon targeted (SCoT) markers. A total of 391 amplified polymorphic bands were generated using 44 ISSR, 9 CDDP, and 12 SCoT primers that produced 255, 35, and 101 polymorphic bands, respectively. The average values of gene diversity were 0.77, 0.67, and 0.81 for ISSR, CDDP, and SCoT markers, respectively. The mean values of polymorphism information content for ISSR, CDDP and SCoT markers were 0.74, 0.63, and 0.80 respectively. The discrimination power of the three approaches for assessing allelic diversity in barley accessions ranked as follows: SCoT > ISSR > CDDP. The barley accessions were classified and clustered into two main groups. Molecular variance analysis revealed 15, 9, and 14% variability among populations with ISSR, CDDP, and SCoT markers, respectively. The Mantel test results revealed that the three molecular marker matrices had significant positive relationships. The SCoT markers might be useful tools for selecting appropriate parents for a breeding program.

Sorghum is an important crop, and starch and phenolic compounds are major and important components in the sorghum grain. However, the underlying critical genetic elements contributing to the rich portfolio of nutrients in sorghum grains are largely unknown. Transcriptomic methods were employed to characterize the expression patterns at five different grain developmental stages of Hongyingzi (an important brewing sorghum), and another two grain sorghums, Jinuoliang 1 and Hongliangfeng 1, for comparison. The uniquely expressed genes were identified at each developmental stage of Hongyingzi when compared with the other two sorghum cultivars. The co-regulated genes at different developmental stages and the regulatory network were determined; the determinant genes and single-nucleotide polymorphisms located at the promoters of these genes involved in starch and phenolic compounds biosynthetic pathways were also identified. These results will provide insights into the potential regulatory network and further contribute to the clarification of the key determinant genes involved in the biosyntheses of starch and phenolic compounds. Meanwhile, some new transcripts and genes were identified at five different developmental stages of grains of the three sorghum cultivars. Our work can provide impetus for further study of the genes responsible for the biosynthesis of starch and phenolic compounds in the sorghum grain, and pave a way for functional validation of a batch of potential genes and single-nucleotide polymorphisms proposed in current work.

Rice is one of the frontline cereals in the world and the major cultivated crop in Bangladesh. A total of eleven simple sequence repeats (SSRs) and thirteen sequence-tagged site (STS) markers were used to characterize twenty-four rice cultivars in Bangladesh. Twenty-four markers generated 60 alleles with 2.5 alleles per locus. The average polymorphism information content (PIC) value was 0.40, while the mean value of heterozygosity, gene diversity, and major allele frequency were recorded as 0.10, 0.48 and 0.62, respectively. However, the SSR markers showed more specificity and a higher discrimination power than the STS markers. The cluster analysis displayed four major clusters with a genetic similarity coefficient value of 0.73. The morphological analyses of the grain identified that Binadhan-20 and BRRI dhan34 had the longest and the shortest seed size, respectively, with a variable correlation between the seed length, width and length/width ratio. The phenol reaction test distinguished seven cultivars as japonica and seventeen cultivars as indica or an intermediate type. All these results regarding the phenotypic data and marker information will be useful for parental selection in modern rice breeding programmes.

Data were obtained in a field experiment carried out at Plant Breeding and Acclimatization Institute Radzikow (central Poland) in 2009-2011. The aim of this study was a multivariate evaluation of 13 advanced lines and cultivars of Festuca rubra, taking into account traits important in seed production. Eleven traits of the grasses and plant resistance to diseases were evaluated. On the basis of multivariate analyses, i.e. hierarchical cluster analysis and principal component analysis, groups of varieties were separated and described, relationships between the traits were evaluated as well. The traits with the biggest influence on multivariate diversity of examined varieties were correlated with the first principal component i.e. height of plants, seeds yield, growth rate of plants, leaf width and time to beginning of earing.

The heading date and growth habit are key factors that regulate the transition from the vegetative to the reproductive stage in barley. In this study, we used PCR based markers to identify the allelic variations in the Vrn-H1 (HvMB5) and Vrn-H2 (HvSNF2) genes and to predict the heading date and growth habit of a collection of Tunisian barley assessed under a semi-arid climate. The allelic variation at HvBM5 revealed two PCR fragments at 830 and 344 bp. Primer sets used to amplify the HvSNF2 gene have resulted in different alleles size of 543, 623, and 700 bp. Different allelic combinations of HVBM5 and HvSNF2 were associated with the heading date and growth habit. The spring and early heading accessions were only characterised by the amplification of the HvSNF2 fragment at 700 bp. All the winter accessions yielded the PCR product HvBM5 at 830 bp, but the variation in the heading date was determined by the HvSNF2 alleles. These DNA markers will be a powerful tool to predict the heading date and growth habit and can be used as markers for the assisted selection to speed up the national breeding programme.

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%.

Fusarium head blight (FHB) is a disease of small grain cereals caused by Fusarium species. The pathogens affect spikes and kernels, resulting in reductions of yield and its quality. The present study was conducted to evaluate variation in the FHB resistance of wheat F₂ hybrids derived from 16 crosses between winter wheat cultivars of various origin and with different susceptibility to FHB. Plants were inoculated with a conidial suspension consisting of a mixture of F. culmorum, F. graminearum and F. avenaceum isolates. After harvest 1000-kernel weight, number of kernels per spike and kernel weight per spike were evaluated in inoculated and control plants. Disease symptoms were observed on kernels of infected plants and the percentage of Fusarium-damaged kernels (FDK) was calculated. The data were statistically evaluated using uni- and multivariate analyses. A significant influence of genotype and treatment on all observed characteristics was detected. Contrasts between control and inoculated plants showed that inoculation lowered the mean values of all the yield-related traits significantly (in the statistical sense). Results of uni- and multivariate analyses enabled us to find three cross combinations which exhibited a low FDK percentage and simultaneously a relatively low reduction of 1000-kernel weight after inoculation. They may be promising for breeding wheat with improved resistance to FHB.

Planting grasses that require low maintenance is a good option for reducing the management input required. The objective of this study was to obtain information about turfgrass characteristics based on spaced-plant characterization and turf performance in turf plots of two selections (Paula hard fescue and Casero colonial bentgrass) recently released for public distribution by the Plant Production Area of the University of Oviedo. The plants were grown under conditions of no irrigation, no fertilizer, no pesticide application and minimal mowing over a 3-year period (2012-2014). The following morphological measurements were done in a spaced-plant nursery: heading date, plant height, inflorescence length and flag leaf length and width. The turf plots were evaluated for several traits including overall turfgrass quality (turf score), leaf texture and genetic colour. In both the spaced-plant nursery and turf trials, hard fescue genotypes displayed better morphological characteristics (narrow leaves, reduced plant height) and performed better (overall high turfgrass quality, fine leaf texture, dark green colour) than bentgrass genotypes under conditions of low maintenance. For areas in which climate, soil characteristics and management conditions are similar to those encountered in this trial, the selection of Paula hard fescue is recommended for use in low-maintenance turf settings because of the good turfgrass performance and morphological characteristics of this selection.

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.

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.

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.

Intercropping of grain legumes and cereals is a promising theme in organic farming for its potential for increasing and stabilizing yields, reducing weed pressure and sustaining plant health. On animal husbandry farms, pea-cereal mixtures may be an interesting crop harvested for green fodder as well as for feed concentrates. Increasing self-sufficiency with fodder is in agreement with the principles of organic agriculture, and it reduces the risks related to the import of soy protein that may be admixed with GM soya. In 2008-2011, plot trials (PT) with intercropped peas and spring cereals (wheat, barley) were conducted. Varieties and pea-cereal combinations were examined to find suitable varieties for intercropping, and the best pea to cereal ratio in the seed intercrop (pea to cereal ratios 80:20, 60:40, 40:60, 20:80). Results show that intercropping peas and spring cereals may be advantageous compared to monocultures. Pea-cereal intercrops produce high yields of green matter and concentrates especially when intercropped at the pea to cereal ratio of 60:40 and 40:60. In 2009, on five certified organic farms, controlled field trials (FT) were conducted with field pea (leaf type), spring barley and spring wheat in monocultures and intercrops (pea to cereal ratio 60:40). Forage yields were evaluated at pea growth phases BBCH-scale 79 and 83. Fresh yields of monocultures and intercrops were evaluated at grain harvest.

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.

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.

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.

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.

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.