Tomato fruit color, which is the most visible characteristic among the other fruit traits, is considered to have a substantial influence on consumers. The pink-colored tomatoes with high soluble solids content are considerably preferred especially in Asia compared to the other colors. Generally the pink fruit trait of tomatoes is easily determined by visual examination of intact fruit, however, it is technically determined by the characteristic of the fruit peel. The pink trait is regulated by variations of the SlMYB12(y) gene located on chromosome 1, which controls the accumulation of the naringenin chalcone, which comprises a large proportion of flavonoids. In this study, we developed a derived Cleaved Amplified Polymorphic Sequences (dCAPS) marker and a sequence characterized amplified regions (SCAR) marker in order to discriminate of pink/non-pinktomatoes in the domestic breeding lines. Quantitative RT-PCR analysis indicated that the SlMYB gene is highly expressed in non-pink fruit peel, whereas the expression is significantly lowered in the pink fruit peel. These gene based markers are expected to enhance the efficiency and accuracy of selection pink-tomatoes in tomato breeding programs.

Platycodon grandiflorum, which is the only species in the genus Platycodon of the family Campanulaceae, is an herbaceous flowering perennial. P. grandiflorum is generally known as bellflower or balloon flower indicating its ornamental uses. It has also been traditionally used as a medicinal crop in East Asia, which is widely employed as an antiphlogistic, antitussive, and expectorant. However, marker-assisted selection and molecular breeding in P. grandiflorum has lagged behind other plants such as pepper and tomato because of the lack of genetic information and effective molecular markers. Transcriptome sequencing provides an effective way to obtain large amount of sequence data when there is no available genome sequence. In this study, we performed a transcriptome analysis in platycodons, which has not been attempted previously. We analyzed simple sequence repeats (SSRs) using RNA-seq data. Di-nucleotide motifs were the most abundant repeats (39% ~ 40%) followed by mono- (26% ~ 32%), tri- (25% ~ 31%), tetra- (1.5% ~ 1.9 %), penta- (0.3% ~ 1%) in three platycodon accessions. Based on the SNP information obtained from RNA-seq analysis, we developed 12 PCR-based markers in Platycodon. The number of alleles ranged from two to seven with the average PIC value of 0.373. These 12 markers were applied to 21 platycodon accessions and a phylogenetic tree was constructed. The markers developed in this study could be introduced in molecular breeding program of platycodons. The SSR information obtained from RNA-seq analysis could be further utilized for developing genic-SSR markers in platycodons. Since platycodon is considered as an orphan crop, which has not been actively deployed for genetic study, the sequence information obtained from this study will contribute to further genetic improvements, genomic information and gene discovery in platycodon