RESUMO
Understanding the transition to the reproductive period is important for crop breeding. This information can facilitate the production of novel varieties that are better adapted to local environments or changing climatic conditions. Here, we report the development of a high-density linkage map based on genotyping-by-sequencing (GBS) for the genus perilla. Through GBS library construction and Illumina sequencing of an F2 population, a total of 9607 single-nucleotide polymorphism (SNP) markers were developed. The ten-group linkage map of 1309.39 cM contained 2518 markers, with an average marker density of 0.56 cM per linkage group (LG). Using this map, a total of six QTLs were identified. These quantitative trait loci (QTLs) are associated with three traits related to flowering time: days to visible flower bud, days to flowering, and days to maturity. Ortholog analysis conducted with known genes involved in the regulation of flowering time among different crop species identified GI, CO and ELF4 as putative perilla orthologs that are closely linked to the QTL regions associated with flowering time. These results provide a foundation that will be useful for future studies of flowering time in perilla using fine mapping, and marker-assisted selection for the development of new varieties of perilla.
Assuntos
Mapeamento Cromossômico/métodos , Perilla/genética , Análise de Sequência de DNA/métodos , Flores/genética , Ligação Genética/genética , Genótipo , Técnicas de Genotipagem , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Fenótipo , Polimorfismo de Nucleotídeo Único/genética , Locos de Características Quantitativas/genéticaRESUMO
A quantitative trait locus (QTL) gw8.1 was detected in the population derived from a cross between the elite japonica cultivar, 'Hwaseong' and Oryza rufipogon (IRGC 105491). Near isogenic lines (NILs) harboring the O. rufipogon segment on chromosome 8 showed increased grain length and weight compared to those of the recurrent parent, Hwaseong. This QTL was mapped to a 175.3-kb region containing 28 genes, of which four were considered as candidates based on the presence of mutations in their coding regions and as per the RNA expression pattern during the inflorescence stage. Leaves and panicles obtained from plants harvested 5 days after heading showed differences in gene expression between Hwaseong and gw8.1-NILs. Most genes were upregulated in O. rufipogon and gw8.1-NIL than in Hwaseong. Scanning electron microscopy analysis of the lemma inner epidermal cells indicated that cell length was higher in gw8.1 NIL than in Hwaseong, indicating that gw8.1 might regulate cell elongation. Among the candidate genes, LOC_Os08g34380 encoding a putative receptor-like kinase and LOC_Os08g34550 encoding putative RING-H2 finger protein were considered as possible candidates based on their functional similarity.
