Genetic mechanism of monocarpic mass flowering and death of Sasa jotanii analyzed by microsatellite DNA markers.

1997年在三仓岛对条谷竹进行了一次结实的大量开花后的幼苗种群进行了研究。利用水稻微卫星DNA位点，以高山不育群体为对照，分析了高山不育群体大量开花的遗传特征。八丈岛三原山。利用R230、RM205、RM254和RM60 4个微卫星位点分别对A、B、C和D的多位点基因进行分析。共提取了50个样本DNA，其中3个来自未开花丛（UF），13个来自再生秆（RC），8个来自再生秆邻近的幼苗（VS），6个来自再生秆非最近邻的幼苗（NN），4个来自Mt.结果表明，A、B、C、D等位基因均在Isl.三仓岛，八丈岛没有。三个分散的人口在山上。三原山岛八丈岛的遗传多样性较差且几乎相同，表明这些种群起源于老年时期的一个连续种群。在三仓岛种群中，位于山东南1公里处的四个NG样本中有三个位于山东南1公里处。Oyama群体不具有HA群体的等位基因位点。A、B和C共现仅见于遗传频率相近的RC和VS，而NN中未发现A。未开花的丛由6个丛生秆组成，其中1个UF只有等位基因A，2个UF没有等位基因，表明该丛由2个以上来自不同基因的无性系组成，这些结果表明等位基因A、B和C的组合诱导了一次结实的大量开花和死亡，而后者则独立于前者，由A作为致死基因的泄漏控制。

Seedling populations following the monocarpic mass flowering of Sasa jotanii in the Mikurajima Island in 1997, regenerating culms and unflowered clump on the Mt. Oyama were analyzed on the genetic aspect of the mass flowering using rice microsatellite DNA loci in comparison with three sterile populations on Mt. Miharayama, Hachijojima Island. Four microsatellite loci, R230, RM205, RM254 and RM60 were used for the analyses with respect to the occurrence of multi-locus genes of A, B, C and D, respectively. A total of 50 sample DNAs including three from an unflowered clump (UF), 13 regenerating culms (RC), eight vicinal seedlings to the RC (VS), six non-nearest neighbour seedlings from the RC (NN), four culms from Mt. Nagataki (NG) and 16 from Hachijojima Island (HA) were used as the template.Occurrence of all alleles of A, B, C and D were limited on the populations or culms of Isl. Mikurajima, while none in Hachijojima. Three scattered populations on Mt. Miharayama, Isl. Hachijojima had poor and almost the same genetic diversity suggested that the populations originated from one continuous population in old ages. Among the Mikurajima populations, three out of four samples of NG that located on 1 km south-east from Mt. Oyama had none allelic loci like as the HA populations. Co-occurrence of A, B and C was found only in RC and VS with similar genetic frequencies, whereas A was not found in NN. The unflowered clump composed of six aggregated culms, among which one UF had only allele A, while two had none showed the clump was composed of more than two clones that originated from distinct genets.These results suggests that a combination of genes such as alleles A, B and C induce the monocarpic mass flowering and death, while the latter will be independent from the former and that controlled by A as a leaky of a lethal gene.