- 著者
- Sogo Nishio Shingo Terakami Toshimi Matsumoto Toshiya Yamamoto Norio Takada Hidenori Kato Yuichi Katayose Toshihiro Saito
- 出版者
- 一般社団法人 園芸学会
- 雑誌
- The Horticulture Journal (ISSN:21890102)
- 巻号頁・発行日
- pp.OKD-093, (Released:2017-07-21)
- 被引用文献数
- 16
The chestnut (genus Castanea) has a long juvenile phase, and breeders have to wait three years or more to evaluate nut traits. Therefore, molecular markers associated with genes of interest are required to speed the selection process in chestnut breeding programs. Genetic linkage maps of the Japanese chestnut were constructed using two breeding populations derived from crosses between ‘Kunimi’ and breeding line ‘709-034’ (Kx709), and between ‘Porotan’ and ‘Tsukuba-43’ (Px43). Maps of the four parents and two integrated maps (one representing each cross) were constructed using 443 simple sequence repeat markers (SSRs) and 554 single-nucleotide polymorphism markers. In the Kx709 integrated map, which was the most saturated of the six maps, 12 linkage groups were identified that covered 668.1 cM with an average distance of 0.8 cM between loci. Using anchor SSRs, these six maps were successfully aligned to the Chinese chestnut consensus map. We evaluated eight important traits, including several nut traits, to identify molecular markers associated with these traits. At least one significant quantitative trait locus (QTL) was detected for each of the eight traits (21 in total). Logarithm of odds (LOD) values and phenotypic variance explained by these QTLs ranged from 2.60 to 7.90 and from 11.6% to 29.1%, respectively. In the Kx709 population analysis, several QTLs for nut harvesting date (HARVEST) and pericarp splitting (SPLIT) were detected. Under the assumption that the effects of these QTLs are additive, the percentage of total phenotypic variance explained by the combination of QTLs was high for both HARVEST (47.5%–60.8%) and SPLIT (33.4%–41.7%). Because these mapping populations and their parents are essential materials for Japanese chestnut breeding programs, these QTLs will soon be used for marker-assisted selection to improve breeding efficiency.
- 著者
- Shigeki Moriya Miyuki Kunihisa Kazuma Okada Hiroshi Iwanami Hiroyoshi Iwata Mai Minamikawa Yuichi Katayose Toshimi Matsumoto Satomi Mori Harumi Sasaki Takashi Matsumoto Chikako Nishitani Shingo Terakami Toshiya Yamamoto Kazuyuki Abe
- 出版者
- 一般社団法人 園芸学会
- 雑誌
- The Horticulture Journal (ISSN:21890102)
- 巻号頁・発行日
- pp.MI-156, (Released:2016-07-23)
- 被引用文献数
- 21
During apple (Malus × domestica Borkh.) storage, a loss in fruit firmness can occur. This is frequently associated with mealiness, an undesirable trait. There have been studies, such as phenotypic analyses and transcriptomics, as well as others employing a transgenic approach, focusing on this trait. Certain genetic approaches, such as quantitative trait loci (QTL) approach, however, have not been attempted. In this study, to identify and characterize QTLs controlling flesh mealiness and to investigate their application in apple breeding, we performed classical QTL mapping based on a bi-parental population and a genome-wide association study (GWAS) of mealiness. Phenotypic data for mealiness allowed us to identify two QTLs in the bi-parental family located on linkage group 10. The GWAS discovered significant marker-trait associations on chromosomes 2, 9, and 10. The MdPG1 locus, located on chromosome 10, was identified as the locus with the strongest significance by both QTL mapping and GWAS, suggesting its primary contribution to flesh mealiness. Using a tri-allelic simple sequence repeat marker, Md-PG1SSR10kd, 10 kb downstream of the MdPG1 coding sequence, we divided apple accessions into six groups based on their genotypes. Among the six groups, the Md-PG1SSR10kd genotype “2/2” had the least mealy phenotype.