시클라멘의 꽃 및 꽃눈의 색, 잎의 모양과 무늬 등의 질적형질에 대한 유전 분석을 위하여 이들의 특성이 다른 계통을 교잡한 후, F1, F2 및 여교잡 세대에서 분리비를 조사하였다. 화색은 F1이 양친의 중간색을 나타냈고, F2는 자방친 화색: 중간 색(F1과 동일): 화분친 화색이 1: 2 : 1로 분리되어 한 쌍의 대립유전자가 불완전우성으로 유전하는 것으로 나타났다. 꽃눈 색은 흰색 × 빨간색 계통의 조합에서 F1 이 빨간색으로 나타났고, F2에서
Late blight caused by Phytophthora infestans is historically a serious epidemic disease in potato and tomato
cultivations. Accession L3708 (Solanum pimpinellifolium), a new source for late blight resistance was identified in AVRDC, and carries the resistance gene, Ph-3, incompatible to P. infestans race 3. The AFLP markers linked to Ph-3 were previously developed from the L3708 accession (Chunwongse et al. 2002). To facilitate tomato breeding with the Ph-3 gene, an attempt was made to convert AFLP markers to sequence-characterized amplified region (SCAR) markers. Among 6 AFLP markers, only one AFLP marker, L87, was successfully converted to SCAR marker. The resistance-specific 230 bp AFLP fragment was cloned and sequenced, and the PCR primer amplifying a 123 bp fragment was designed. This SCAR marker could discriminate resistant and susceptible individuals with high stringency. The developed SCAR marker could be used for the marker assisted-selection in tomato breeding programs.
Cytoplasmic male sterility (CMS) and fertility restoration have been utilized as valuable tools for F_1-hybrid seed production in many crops despite laborious breeding processes. Molecular markers for the selection of CMS-related genes help reduce the expenses and breeding times. A previously reported genomic region containing the Ppr-B gene, which is responsible for restoration of fertility and corresponds to the Rfo locus, was used to develop gene-based or so-called "functional" markers for allelic selection of the restorer-of-fertility gene (Rfo) in F_1-hybrid breeding of radish (Raphanus sativus L.) Polymorphic sequences among Rfo alleles of diverse breeding lines of radish were examined by sequencing the Ppr-B alleles. However, presence of Ppr-B homolog, designated as Ppr-D, interferes on specific PCR amplification of Ppr-B in certain breeding lines. The organization of Ppr-D, resolved by genome walking, revealed extended homology with Ppr-B even in the promoter region. Interestingly, PCR amplification of Ppr-D was repeatedly unsuccessful in certain breeding lines implying the lack of Ppr-D in these radishes. Ppr-B could only be successfully amplified for analysis through designing primers based on the sequences unique to Ppr-B that exclude interference from Ppr-D gene. Four variants of Rfo alleles were identified from 20 breeding lines. A combination of three molecular markers was developed in order to genotype the Rfo locus based on polymorphisms among four different variants. These markers will be useful in facilitating F_1-hybrid cultivar development in radish.
Self incompatibility (SI) of Cruciferous crop has been studied not only to find out the evolution of the self incompat-ibility system, but also to identify the S haplotypes of the plant materials on the practical breeding programs. It has been reportedtha