Department of Horticulture, Michigan State University, East Lansing, MI, 48824, USA.
Sci Rep. 2017 Jun 9;7(1):3200. doi: 10.1038/s41598-017-03528-9.
The rate at which plants develop new nodes (development rate) is a major determinant of crop production time, yet the genetic control of this process, including genetic interactions with crop quality parameters, is poorly understood. We employed a modified genotyping-by-sequencing approach and generated genetic linkage maps with 6,291 and 3,297 single nucleotide polymorphisms (SNPs) for the interspecific Petunia recombinant inbred line (RIL) population - P. axillaris × P. exserta (AE) and P. integrifolia × P. axillaris (IA), respectively. Comparative mapping between the populations revealed perfect collinearity of marker order but different recombination frequency at the corresponding linkage groups (LGs). Quantitative trait loci (QTL) mapping conducted for development traits and other important quality traits indicated QTL clustered on chromosome 1, 2, 4 and 6 for the AE population and chromosome 1, 2, 5 and 6 for the IA population. Additionally, 209 differentially expressed unique transcripts were identified in shoot apex tissue between fast- and slow-developing RILs, 13 of which mapped to within 1 cM of a development rate QTL. These results will facilitate the identification of novel genes controlling crop timing and quality traits in Petunia and highlight the power of using multiple interspecific populations to elucidate genetic determinants of natural variation.
植物形成新节点（发育速度）的速度是决定作物生产时间的主要因素，但该过程的遗传控制，包括与作物质量参数的遗传相互作用，仍知之甚少。我们采用了改良的测序分型方法，分别为种间 Petunia 重组自交系（RIL）群体 - P. axillaris×P. exserta (AE) 和 P. integrifolia×P. axillaris (IA) 生成了 6291 个和 3297 个单核苷酸多态性（SNP）的遗传连锁图谱。群体间的比较作图揭示了标记顺序的完美共线性，但相应连锁群（LG）的重组频率不同。对发育性状和其他重要质量性状进行的数量性状基因座（QTL）作图表明，AE 群体的 QTL 聚集在第 1、2、4 和 6 号染色体上，IA 群体的 QTL 聚集在第 1、2、5 和 6 号染色体上。此外，在快速发育和慢速发育的 RIL 之间的茎尖组织中鉴定出 209 个差异表达的独特转录本，其中 13 个映射到发育速度 QTL 的 1cM 内。这些结果将有助于鉴定控制矮牵牛作物时间和质量性状的新基因，并强调使用多个种间群体阐明自然变异遗传决定因素的力量。
