| Segregation distortion of Mendelian genes induced by
cytoplasm effect O.G. DAVYDENKO Institute of Genetics and Cytology of the Byelorussian Academy of Sciences, Minsk, USSR Extensive investigations carried out with wheat alloplasmic lines are evidence of various and significant expression changes of morphological and agronomic traits (TSUNEWAKI 1980). At the same time there are some facts demonstrating cytoplasm influence on chromosome transmission processes (ENDO 1979, TSUJI & MAAN 1981), mutation rate change (PONAJOTOV 1983) and sister chromatid exchange rate (LUGININ et al. 1987). These data show that cytoplasms affect not only characters expression controlled with nuclear genes, but changes of nuclear genes frequency in plant populations. Introduction of the recessive mutant nuclear gene responsible for genic male sterility in 11 alloplasmic lines with genome of Chinese Spring has demonstrated significant and various changes of segregation distortion, which can be explained by plasmagene effect on selective gametes advantages and changes of nuclear genes recombination (DAVYDENKO 1984, 1985). In this paper it is reported of cytoplasm influence on numeraical segregation ratios for morphological marker traits. Material and Methods Alloplasmic wheat lines with genome of var. Chinese Spring and cytoplasms of Aegilops and Triticum species were used as maternal components of crosses : C04 - cytoplasm of Ae. squarrosa; C05 - Ae. comosa; C08 - Ae. speltoides; C10 - Ae. sharonensis; C21 - T. dicoccoides; C22 - T. dicoccum; C28 - Ae. cylindrica; C33 - Ae. variabilis; C34 - Ae. kotschyi; C36 - Ae. ventricosa; C53 - Ae. juvenalis; C55 - Ae. crassa 6X; C56 - Ae. vavilovii and C52 line - euplasmic analogue with cytoplasm of Triticum aestivum. Alloplasmic line seeds were kindly given by Prof. K. TSUNEWAKI. MS63 mutant line (VOLODIN et al. 1982) and K31362 line received from VIR collection were used as pollen parents. Both lines have awned and hairy ear glumes. F1 hybrid plants were tested for presence of hairy glumes and among F2 plants segregation analysis for these two characters was carried out. |
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