Experimental evolutionary studies on the genetic autonomy of the cytoplasmic genome "plasmon" in the (wheat)- complex.

The term "plasmon" is used to indicate the whole cytoplasmic genetic system, whereas "genome" refers to the whole nuclear genetic system. Although maternal inheritance of the plasmon is well documented in angiosperms, its genetic autonomy from the coexisting nuclear genome still awaits critical examination. We tested this autonomy in two related studies: One was to determine the persistence of the genetic effect of the plasmon of (genome CC) on the phenotype of common wheat, strain "Tve" (genome AABBDD), during 63 y (one generation per year) of repeated backcrosses of and its offspring with pollen of the same Tve wheat, and the second was to reconstruct an strain from the genome of this strain and its plasmon that had been resident in Tve wheat for 50 generations, and to compare the phenotypic and organellar DNA characteristics between the native and reconstructed strains.

Memoir on the origin of wheat stocks used by Prof. Tetsu Sakamura, on the centennial of his discovery of the correct chromosome number and polyploidy in wheat.

Sakamura (1918) reported the discovery of a polyploid series among eight species of the genus Triticum; this series consisted of 2x, 4x and 6x species with 2n = 14, 28 and 42 chromosomes, respectively. He mentioned in this article that all the materials he used were gifted by T. Minami of the same department of Hokkaido University, Japan.

Fine mapping of the first multi-fertility-restoring gene, Rf(multi), of wheat for three Aegilops plasmons, using 1BS-1RS recombinant lines.

Fertility-restoring genes, Rfv1, Rfm1 and Rfn1, respectively, for the male sterile cytoplasms of Aegilops kotschyi, Ae. mutica and Ae. uniaristata to common wheat were located on the same locus of Pavon wheat 1BS arm.

Genetic effect of the Aegilops caudata plasmon on the manifestation of the Ae. cylindrica genome.

In the course of reconstructing Aegilops caudata from its own genome (CC) and its plasmon, which had passed half a century in common wheat (genome AABBDD), we produced alloplasmic Ae. cylindrica (genome CCDD) with the plasmon of Ae. caudata.

Interorganellar DNA transfer in wheat: dynamics and phylogenetic origin.

A homology search of wheat chloroplast (ct) and mitochondrial (mt) genomes identified 54 ctDNA segments that have homology with 66 mtDNA segments. The mtDNA segments were classified according to their origin: orthologs (prokaryotic origin), xenologs (interorganellar DNA transfer origin) and paralogs (intraorganellar DNA amplification origin). The 66 mtDNA sequences with homology to ctDNA segments included 14 paralogs, 18 orthologs and 34 xenologs.