Ungerer Mark C, Halldorsdottir Solveig S, Modliszewski Jennifer L, Mackay Trudy F C, Purugganan Michael D
Department of Genetics, North Carolina State University, Raleigh, North Carolina 27695, USA.
Genetics. 2002 Mar;160(3):1133-51. doi: 10.1093/genetics/160.3.1133.
Variation in inflorescence development patterns is a central factor in the evolutionary ecology of plants. The genetic architectures of 13 traits associated with inflorescence developmental timing, architecture, rosette morphology, and fitness were investigated in Arabidopsis thaliana, a model plant system. There is substantial naturally occurring genetic variation for inflorescence development traits, with broad sense heritabilities computed from 21 Arabidopsis ecotypes ranging from 0.134 to 0.772. Genetic correlations are significant for most (64/78) pairs of traits, suggesting either pleiotropy or tight linkage among loci. Quantitative trait locus (QTL) mapping indicates 47 and 63 QTL for inflorescence developmental traits in Ler x Col and Cvi x Ler recombinant inbred mapping populations, respectively. Several QTL associated with different developmental traits map to the same Arabidopsis chromosomal regions, in agreement with the strong genetic correlations observed. Epistasis among QTL was observed only in the Cvi x Ler population, and only between regions on chromosomes 1 and 5. Examination of the completed Arabidopsis genome sequence in three QTL regions revealed between 375 and 783 genes per region. Previously identified flowering time, inflorescence architecture, floral meristem identity, and hormone signaling genes represent some of the many candidate genes in these regions.
花序发育模式的变异是植物进化生态学的核心因素。在模式植物系统拟南芥中，研究了与花序发育时间、结构、莲座叶形态和适合度相关的13个性状的遗传结构。花序发育性状存在大量自然发生的遗传变异，根据21个拟南芥生态型计算出的广义遗传力范围为0.134至0.772。大多数（64/78）性状对之间的遗传相关性显著，表明位点间存在多效性或紧密连锁。数量性状位点（QTL）定位表明，在Ler x Col和Cvi x Ler重组自交系定位群体中，花序发育性状分别有47个和63个QTL。几个与不同发育性状相关的QTL定位于拟南芥的同一染色体区域，这与观察到的强遗传相关性一致。仅在Cvi x Ler群体中观察到QTL间的上位性，且仅在第1和第5号染色体区域之间。对三个QTL区域中已完成的拟南芥基因组序列的检查显示，每个区域有375至783个基因。先前鉴定的开花时间、花序结构、花分生组织特性和激素信号基因是这些区域众多候选基因中的一部分。
