Ishikawa Naoko, Yokoyama Jun, Ikeda Hiroshi, Takabe Eriko, Tsukaya Hirokazu
National Institute for Basic Biology/Okazaki Institute for Integrative Bioscience, National Institutes of Natural Sciences, Okazaki 444-8585, Japan.
J Plant Res. 2006 Jul;119(4):385-95. doi: 10.1007/s10265-006-0286-y. Epub 2006 Jun 14.
Morphological and molecular variations in Plantago asiatica L. var. densiuscula Pilg. were analyzed to evaluate the genetic basis for recognizing the dwarf variety P. asiatica var. yakusimensis (Masam.) Ohwi. Considerable variation in the leaf size of P. asiatica var. densiuscula was observed, and no morphological discontinuities were found between the dwarf types of P. asiatica var. densiuscula and P. asiatica var. yakusimensis. Morphological analysis of plants grown under standardized conditions revealed that both environmental plasticity and genetic differentiation contributed to the dwarfisms. Molecular phylogenetic analysis of rDNA internal transcribed spacer (ITS) regions and the SUC1 locus encoding a sucrose transporter revealed that P. asiatica var. yakusimensis was genetically unique although the differentiation level was low. From the above results, we concluded that P. asiatica var. yakusimensis should be reduced to a form of P. asiatica var. densiuscula. Furthermore, the geographic distribution of the SUC1 genotype suggested multiple origins of dwarves, and possible hypotheses for the origins of dwarves are discussed.
对密花车前（Plantago asiatica L. var. densiuscula Pilg.）的形态和分子变异进行了分析，以评估将矮化变种雅库什车前（P. asiatica var. yakusimensis (Masam.) Ohwi）作为一个独立变种识别的遗传基础。观察到密花车前的叶大小存在相当大的变异，并且在密花车前的矮化类型与雅库什车前之间未发现形态上的间断。对在标准化条件下生长的植株进行的形态分析表明，环境可塑性和遗传分化都对矮化现象有影响。对核糖体DNA内转录间隔区（ITS）区域和编码蔗糖转运蛋白的SUC1位点进行的分子系统发育分析表明，尽管雅库什车前的分化水平较低，但在遗传上是独特的。根据上述结果，我们得出结论，雅库什车前应被归为密花车前的一个变型。此外，SUC1基因型的地理分布表明矮化植株有多个起源，并对矮化植株的起源可能假说进行了讨论。
