Cao Zhe, Guo Yufang, Yang Qian, He Yanhong, Fetouh Mohammed I, Warner Ryan M, Deng Zhanao
1Department of Environmental Horticulture, Gulf Coast Research and Education Center, IFAS, University of Florida, 14625 County Road 672, Wimauma, FL 33598 USA.
2Department of Horticulture, Michigan State University, East Lansing, MI 48824 USA.
Hortic Res. 2019 Feb 1;6:27. doi: 10.1038/s41438-018-0091-5. eCollection 2019.
Petunia is a very important flower in the global floriculture industry and has played a critical role as a model in plant genetic studies. Owing to limited genetic variability in commercial germplasm, development of novel petunia phenotypes and new varieties has become increasingly difficult. To enrich petunia germplasm and facilitate genetic improvement, it is important to explore genetic variation in progenitor species that may contain highly valuable genes/alleles. In this study, an interspecific recombinant inbred population (168 recombinant inbreds) derived from × were phenotyped for days to anthesis (DTA), flower count (Flower_C), flower diameter (Flower_D), flower length (Flower_L), plant height (Plant_H), plant spread (Plant_S), and plant size (Plant_Z) in 2014 and 2015. Transgressive segregation was observed for all traits in both years. The broad-sense heritability on a 2-year basis varied from 0.38 (Flower_C) to 0.82 (Flower_L). Ten QTL were consistently identified in both years and by two mapping strategies [multiple QTL mapping (MQM) in MapQTL and inclusive composite interval mapping (ICIM) in IciMapping]. Major QTL explained up to 30.2, 35.5, and 47.1% of the total phenotypic variation for Plant_S, Flower_L, and Flower_D, respectively. These findings should be of significant values for introgression of desirable genes from wild petunias into commercial varieties and future genetic improvement of this important flower.
矮牵牛是全球花卉产业中一种非常重要的花卉，在植物遗传学研究中作为模式植物发挥了关键作用。由于商业种质的遗传变异性有限，开发新的矮牵牛表型和新品种变得越来越困难。为了丰富矮牵牛种质并促进遗传改良，探索可能包含高价值基因/等位基因的祖先物种的遗传变异非常重要。在本研究中，对源自×的种间重组自交群体（168个重组自交系）在2014年和2015年进行了花期天数（DTA）、花朵数量（Flower_C）、花直径（Flower_D）、花长度（Flower_L）、株高（Plant_H）、株幅（Plant_S）和植株大小（Plant_Z）的表型分析。两年中所有性状均观察到超亲分离。两年的广义遗传力从0.38（Flower_C）到0.82（Flower_L）不等。通过两种定位策略[MapQTL中的多QTL定位（MQM）和IciMapping中的包容性复合区间定位（ICIM）]在两年中一致鉴定出10个QTL。主要QTL分别解释了植株大小、花长度和花直径总表型变异的30.2%、35.5%和47.1%。这些发现对于将野生矮牵牛的优良基因导入商业品种以及该重要花卉未来的遗传改良具有重要价值。
