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‘Titi Chal’ with elite characteristics and high fruit yield was developed from a cross between ‘MS-BGT’ and ‘NHMF’ in 2009. The cultivar has multiple disease resistances against Tobacco mosaic virus, Tomato yellow leaf curl virus, Tomato spotted wilt virus and Leaf mold disease. The early and medium-maturing variety can be transplanted on July to September. The cherry tomato presents longer shelf-life due to higher fruit firmness and also has high eating quality with 9~10 brix of sugar content. The fruit shape is red plum type with an average fruit weight of 23~25 g. The ‘Titi Chal’ is more reliable to be cultivated because of medium-strong plant-vigor and low occurrence of creased stem.

‘TY Altorang’ was developed from a cross between ‘MS-CDE’ and ‘VFR’ in 2009. The cultivar has multi-disease resistances against Tobacco mosaic virus(TMV), Tomato yellow leaf curl virus(TYLCV), Fusarium crown and root rot and Leaf mold disease. Additionally, this cultivar produces larger fruit set resulting in higher fruit harvest. Fruit shape is fair and uniformed ovate type with an average fruit weight of 225 g as a beef-steak type tomato, and the fruit presents longer shelf-life due to higher fruit firmness. The early and medium-maturing variety can be transplanted in February to March, or July to September. Medium-strong plant-vigor and low occurrence of creased stem allow, relativey easy cultivation.

Chili veinal mottle virus (ChiVMV) is one of the most destructive pepper pathogens in Asia. Development of ChiVMV-resistant cultivars is necessary to control ChiVMV infection on pepper farms. However, sources of variation for ChiVMV resistance have not been identified and only a recessive resistance gene has been identified. We initially screened 30 pepper lines from several countries using inoculation tests to further examine inheritance of ChiVMV resistance, to establish a relevant breeding program, and to develop a new resistant line. Here, we report a new genetically dominant source of resistance to ChiVMV in pepper. Secondly, we found two amplified fragment length polymorphisms linked to dominant resistance and converted them into high-resolution melting markers, which were located on chromosome 6. Furthermore, we obtained a cleaved amplified polymorphic sequence marker that was closer to the ChiVMV resistance locus using comparative mapping. The newly discovered marker, related to a single dominant gene, will help researchers develop a new ChiVMV-resistant pepper cultivar.

With 4 figures and 1 table Abstract The characteristics of male sterility (MS) are used in breeding programmes to achieve economical seed production. Male sterility is divided into genic male sterility (GMS) and cytoplasmic male sterility (CMS), which are used to breed commercial pepper varieties. The CMS system, however, is not feasible in some pepper varieties, including bell peppers, because of the absence of a restorer source. GMS is thus important for seed production in bell peppers. In this study, a GMS-linked marker from bell peppers was developed using the bulked segregant analysis (BSA) and amplified fragment length polymorphism (AFLP) method using F2 and sibling individuals. We used 1024 AFLP primer sets and found a polymorphism from EcoRI ACG/MseI GTT among the siblings. An internal sequence-based primer was designed from the 395 bp sequence for high-resolution melting (HRM) analysis, and the marker score of 87 of 92 F2 individuals corresponded to their phenotypes. The marker was mapped on chromosome 5 on the AC99 map.

Tomato hypocotyl can generally be one of two colors, purple or green. Genetically, this trait is controlled by a single dominant gene. Hypocotyl tissue specific color expression is one of many visible genetic marker sources used to select tomato progeny. However, the visible marker does not show a clear distinction between homozygous genotype and heterozygous genotype from the breeding lines. Therefore, to identify a hypocotyl pigmentation related marker, we screened DNA polymorphisms in thirteen tomato lines showing purple or green hypocotyls. The markers used for screening consisted of primer set information obtained from anthocyanin related genes, conserved ortholog set Ⅱ (COS Ⅱ) marker sets localized near anthocyanin related genes, and restriction fragment length polymorphism (RFLP) markers localized near COS Ⅱ markers, which produce polymorphisms between purple and green tomatoes. One primer from a RFLP fragment resulted in a polymorphism on agarose gel electrophoresis. From the RFLP fragment, a cleaved amplified polymorphic sequence (CAPS) marker was developed to distinguish between purple and green hypocotyls. The genotypes of 135 F2 individuals were analyzed using the CAPS marker, and among them, 132 individuals corresponded to the phenotypes of hypocotyl pigmentation.

A pepper genetic map was constructed from F2 mapping population of 93 individuals from a cross between Capsicum annuum ‘F68’ and C. chinense ‘Habanero’. Surrey was made for the map distribution and polymorphism level of these marker groups; reverse random amplification microsatellite polymorphism (rRAMP), WRKY and amplified fragment length polymorphisms (AFLP). A total of 912 molecular markers [356 rRAMP, 190 WRKY, 305 AFLP, and 61 simple sequence repeats (SSR)] were developed in this study. The rRAMP and WRKY markers were more evenly scattered in the pepper genome than the AFLP and SSR markers, and filled the gaps not populated by the other markers. The interspecific pepper map contained 28 linkage groups with 625 linked markers and covered 3377.2 cM with an average interval of 5.9 cM. On the basis of the map, the fruit length quantitative trait locus (QTL) was analyzed and these QTL regions were detected near rRAMP and WRKY markers on the chromosome 3, 5, 11, and LG3. These marker system, map information, and detected QTLs could be one of basic information for pepper research.

Map-based cloning to find genes of interest, markerassisted selection (MAS), and marker-assisted breeding (MAB) all require good genetic maps with high reproducible markers. For map construction as well as chromosome assignment, development of single copy PCR-based markers and map integration process are necessary. In this study, the 132 markers (57 STS from BAC-end sequences, 13 STS from RFLP, and 62 SSR) were newly developed as single copy type PCR-based markers. They were used together with 1830 markers previously developed in our lab to construct an integrated map with the Joinmap 3.0 program. This integrated map contained 169 SSR, 354 RFLP, 23 STS from BAC-end sequences, 6 STS from RFLP, 152 AFLP, 51 WRKY, and 99 rRAMP markers on 12 chromosomes. The integrated map contained four genetic maps of two interspecific (Capsicum annuum 'TF68' and C. chinense 'Habanero') and two intraspecific (C. annuum 'CM334' and C. annuum 'Chilsungcho') populations of peppers. This constructed integrated map consisted of 805 markers (map distance of 1858 cM) in interspecific populations and 745 markers (map distance of 1892 cM) in intraspecific populations. The used pepper STS were first developed from end sequences of BAC clones from Capsicum annuum 'CM334'. This integrated map will provide useful information for construction of future pepper genetic maps and for assignment of linkage groups to pepper chromosomes.

The FLO/LFY genes of plants regulate the transition from inflorescence to floral meristem. To isolate the FLO/LFY ortholog in pepper (Capsicum annuum), RT-PCR was performed using primer pairs derived from the conserved sequences of other FLO/LFY orthologs; a partial 948-bp DNA fragment was obtained. A 1,251-bp full coding sequence of the FLO/LFY-like gene homolog was identified after a pepper cDNA library screening and was designated CaLFY. The CaLFY DNA sequence was 3,982 bp long, containing three exons and two introns. CaLFY was predicted to encode a protein sharing 77%, 79%, and 78% identity, respectively, with FA (tomato), NFL1 (tobacco), and ALF (petunia), the FLO/LFY ortholog proteins in Solanaceae. Semiquantitative RT-PCR revealed that CaLFY transcripts were abundantly expressed in floral tissue. Through genetic mapping, CaLFY was placed into the middle of pepper chromosome 3; its location showed close synteny with FA on tomato chromosome 3. Overexpression of CaLFY cDNA under the control of a CaMV 35S promoter in tobacco caused leaf tissue to form at the floral meristem. Moreover, a severe early-flowering phenotype was observed. Taken together, these results indicate that CaLFY is a putative pepper ortholog of FLO/LFY.

Cold induces expression of a number of genes that encode proteins that enhance tolerance to freezing temperatures in plants. A cis-acting element responsive to cold and drought, the C-repeat/dehydration-responsive element (C/DRE), was identified in the Arabidopsis thaliana stress-inducible genes RD29A and COR15a and found in other cold-inducible genes in various plants. C/DRE-binding factor/DRE-binding protein (CBF/DREB) is an essential component of the cold-acclimation response, but the signaling pathways and networks are mostly unknown. Here we used targeted genetic approach to isolate A. thaliana mutants with altered cold-responsive gene expression (acg) and identify ACG1 as a negative regulator of the CBF/DREB pathway. acg1 flowered late and had elevated expression of FLOWERING LOCUS C (FLC), a repressor of flowering encoding a MADS-box protein. We showed that acg1 is a null allele of the autonomous pathway gene FVE. FVE encodes a homolog of the mammalian retinoblastoma-associated protein, a component of a histone deacetylase (HDAC) complex involved in transcriptional repression. We also showed that plants sense intermittent cold stress through FVE and delay flowering with increasing expression of FLC. Dual roles of FVE in regulating the flowering time and the cold response may have an evolutionary advantage for plants by increasing their survival rates.

Despite increasing awareness of the importance of WRKY genes in plant defense signaling, the locations of these genes in the Capsicum genome have not been established. To develop WRKY-based markers, primer sequences were deduced from the conserved sequences of the DNA binding motif within the WRKY domains of tomato and pepper genes. These primers were derived from upstream and downstream parts of the conserved sequences of the three WRKY groups. Six primer combinations of each WRKY group were tested for polymorphisms between the mapping parents, C. annuum 'CM334' and C. annuum 'Chilsungcho'. DNA fragments amplified by primer pairs deduced from WRKY Group II genes revealed high levels of polymorphism. Using 32 primer pairs to amplify upstream and downstream parts of the WRKY domain of WRKY group II genes, 60 polymorphic bands were detected. Polymorphisms were not detected with primer pairs from downstream parts of WRKY group II genes. Half of these primers were subjected to F2 genotyping to construct a linkage map. Thirty of 41 markers were located evenly spaced on 20 of the 28 linkage groups, without clustering. This linkage map also consisted of 199 AFLP and 26 SSR markers. This WRKY-based marker system is a rapid and simple method for generating sequence-specific markers for plant gene families.

Phytophthora capsici Leonian, an oomycete pathogen, is a serious problem in pepper worldwide. Its resistance in pepper is controlled by quantitative trait loci (QTL). To detect QTL associated with P. capsici resistance, a molecular linkage map was constructed using 100 F(2) individuals from a cross between Capsicum annuum 'CM334' and C. annuum 'Chilsungcho'. This linkage map consisted of 202 restriction fragment length polymorphisms (RFLPs), 6 WRKYs and 1 simple sequence repeat (SSR) covering 1482.3 cM, with an average interval marker distance of 7.09 cM. QTL mapping of Phytophthora root rot and damping-off resistance was performed in F(2:3) originated from a cross between resistant Mexican landrace C. annuum 'CM334' and susceptible Korean landrace C. annuum 'Chilsungcho' using composite interval mapping (CIM) analysis. Four QTL explained 66.3% of the total phenotypic variations for root rot resistance and three 44.9% for damping-off resistance. Of these QTL loci, two were located close to RFLP markers CDI25 on chromosome 5 (P5) and CT211A on P9. A bacterial artificial chromosome (BAC) library from C. annuum 'CM334' was screened with these two RFLP probes to obtain sequence information around the RFLP marker loci for development of PCR-based markers. CDI25 and CT211 probes identified seven and eight BAC clones, respectively. Nine positive BAC clones containing probe regions were sequenced and used for cytogenetic analysis. One single-nucleotide amplified polymorphism (SNAP) for the CDI25 locus, and two SSRs and cleaved amplified polymorphic sequence (CAPS) for CT211 were developed using sequences of the positive BAC clones. These markers will be valuable for rapid selection of genotypes and map-based cloning for resistance genes against P. capsici.

The fabrication of nanometer-scale features such as quantum dots and quantum wires, in a controllable and economically viable manner is one of essential requirements for the production of highly functional devices. Here, we propose a new electron beam projection lithography technique for patterning nanometer scale, periodic structures. The novelty of this technique is that the crystalline lattice image observed by high resolution transmission electron microscopy (HRTEM) is employed as the ultimate mask to define nanometer scale pattern. Namely, the Angstrom-scale lattice image of a crystalline material is magnified within the electron microscope, and is projected onto an electron-beam-resist-coated substrate. This technique is tentatively called AIPEL (atomic image projection electron-beam lithography).

We present a method for the formation of sub-10 nm scale silicide dots by applying e-beam energy. Our process demonstrates a hybrid approach which combines the "top down approach" -defining the area in which the dots are formed -and "bottom up approach" -which enables the formation of high density sub-10 nm scale dots below the resolution limit of e-beam patterning - in a single step process.

Summary Low temperature induces a number of genes that encode the proteins promoting tolerance to freezing, mediated by ABA-dependent and ABA–independent pathways in plants. The cis-acting element called C/DRE is known to respond to low temperature independently of ABA action. To investigate the signalling and network of ABA-independent pathways, the transgenic Arabidopsis plants were generated containing several copies of the C/DRE derived from cor15a gene with a minimal promoter fused to a GUS reporter gene. The transgenic plants containing four copies of the C/DRE (4C/DRE-GUS) showed responsiveness to cold and drought treatments and were used for characterization of cold signalling and cross-talk. Cold-induced GUS expression was inhibited by okadaic acid at 1 nm, indicating that protein phosphatase 2A might act as a positive regulator. Light was shown to activate cold- and drought-induced GUS expression. Photo-reversibility of the GUS mRNA by red and far-red light with concomitant cold treatment suggests a role of phytochrome as a photoreceptor in mediating light signalling to activate the cold-induced gene expression through the C/DRE. Furthermore, GUS expression analysis in phyA or phyB or phyAphyB mutant backgrounds showed that phytochrome B is a primary photoreceptor responsible for the activation of cold-stress signalling in response to light. Light enhanced the induction kinetics of CBF1, 2, and 3 encoding the cognate transcription factors, and cor15a, in a consecutive manner compared to the dark condition in the cold, suggesting that the connection point between cold and light signalling mediated by phytochrome is at a higher step than the expression of CBF genes.

Phytophthora infestans is the causal agent of late blight in potato. The Mexican species Solanum demissum is well known as a good resistance source. Among the 11 R gene differentials, which were introgressed from S. demissum, especially R8 and R9 differentials showed broad spectrum resistance both under laboratory and under field conditions. In order to gather more information about the resistance of the R8 and R9 differentials, F1 and BC1 populations were made by crossing Mastenbroek (Ma) R8 and R9 clones to susceptible plants. Parents and offspring plants were examined for their pathogen recognition specificities using agroinfiltration with known Avr genes, detached leaf assays (DLA) with selected isolates, and gene-specific markers. An important observation was the discrepancy between DLA and field trial results for Pi isolate IPO-C in all F1 and BC1 populations, so therefore also field trial results were included in our characterization. It was shown that in MaR8 and MaR9, respectively, at least four (R3a, R3b, R4, and R8) and seven (R1, Rpi-abpt1, R3a, R3b, R4, R8, R9) R genes were present. Analysis of MaR8 and MaR9 offspring plants, that contained different combinations of multiple resistance genes, showed that R gene stacking contributed to the Pi recognition spectrum. Also, using a Pi virulence monitoring system in the field, it was shown that stacking of multiple R genes strongly delayed the onset of late blight symptoms. The contribution of R8 to this delay was remarkable since a plant that contained only the R8 resistance gene still conferred a delay similar to plants with multiple resistance genes, like, e.g., cv Sarpo Mira. Using this “de-stacking” approach, many R gene combinations can be made and tested in order to select broad spectrum R gene stacks that potentially provide enhanced durability for future application in new late blight resistant varieties. Electronic supplementary material The online version of this article (doi:10.1007/s00122-011-1757-7) contains supplementary material, which is available to authorized users.