| Interactions between chromosome 1D of common wheat
and Aegilops uniaristata cytoplasm H. TSUJIMOTO1), S. TSUJI2) and K. TSUNEWAKI Laboratory of Genetics, Faculty of Agriculture, Kyoto University, Kyoto 606, Japan By biological and biochemical investigations, all the cytoplasms of Triticum and Aegilops species were classified into 16 plasma types (TSUNEWAKI & TSUJIMOTO 1984). According to this classification, cytoplasm of Ae. uniaristata belongs to the plasma type Mu. This cytoplasm causes complete male sterility in three of the 12 common wheats which were used as the nucleus donor to the alloplasmic lines, but no alterations of the other morphological and physiological characters. The male sterility manifested in the three lines is controlled by a fertility-restoring gene, Rfun1, on the short arm of chromosome 1B (MUKAI 1983). In this paper we report a gene(s) on chromosome 1D that suppresses the seed shriviling of the alloplasmic lines having the Ae. uniaristata cytoplasm. Materials and Methods An alloplasmic line of common wheat cultivar Chinese Spring carrying Aegilops uniaristata cytoplasm was used in the present investigation. This line, abbreviated (uniaristata)-CS, was produced by more than four backcrosses of normal Chinese Spring (CS) as recurrent male parent to (uniaristata)-Selkirk produced by MAAN (1977). Ditelocentrics and nulli-tetrasomics (SEARS 1965, SEARS & SEARS 1978) of the first homoeologous-group chromosomes were used in the aneuploid analysis of the suppressor of seed shriveling caused by this cytoplasm. The cross combinations for the production of the alloplasmic aneuploid lines are mentioned in "Results and Discussion". Pollen grains from anthers in the anthesis stage were mounted on microslides in a mixture (1 : 1) of acetocarmine and glycerine. Pollen fertility was estimated by the percent of fertile pollen grains having three developed nuclei. Selfed seed fertility was determined by recording the percentage of seed set in the first and second florets of spikelets of bagged spikes. The basal and apical spikelets were excluded from the determination. Chromosome constitution in root tip cells and configuration in pollen mother cells were observed by usual acetocarmine squash and smear method, respectively. |
| 1) Present address : Kihara Institute for Biological
Research, Yokohama City University, Mutsukawa 3-122-20, Minami-ku, Yokohama
232, Japan. 2) Present address : Takarazuka Research Center, Sumitomo Chemical Co. Ltd., Takarazuka 665, Japan. |
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