Budget Amount *help |
¥2,100,000 (Direct Cost: ¥2,100,000)
Fiscal Year 1993: ¥500,000 (Direct Cost: ¥500,000)
Fiscal Year 1992: ¥1,600,000 (Direct Cost: ¥1,600,000)
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Research Abstract |
Interfamilial and intergeneric somatic cell hybridization among a gramineous species (Oryza sativa L., strain A-58) and three leguminous species soybean (Glycine max (L.) Merr., cv.Harosoy), alfalfa (Medicago sativa L., cv.Dupuit) and birdsfoot trefoil (Lotus corniculatus L., cv.Viking) were examined. Both fragments of parent in some cases and altered mtDNAs were observed in the restriction profiles and Southern blots of 5 combinations of somatic hybrid calli. On the other hand, nuclear DNAs and cpDNAs were the same as those of one parent and they were identical with those of soybean, alfalfa or birdsfoot trefoil, for the banding patterns of restriction profiles and Southern blots in somatic hybrid calli. Therefore, it is assumed that some kinds of interaction between nucleus and cytoplasmic organelle and selective disadvantage for rice nucleus promote such a uniparental segregation of cpDNA.So far, it has been indicated that the organization of mitochondrial genome is correlative with morphological and physiological functions of plants. In this study, regenerated hybrid plants of soybean and birdsfoot trefoil, and of rice and birdsfoot trefoil, showed the morphological and physiologically abnormality. Actually, some regenerants from the hybrid calli of rice and birdfoot trefoil were tolerant of low temperature and low sunlight intensity in green house at wintertime. Thus, it is suggested that these regenerated hybrid plants presumably have the altered mtDNAs, as well as hybrids calli analyzed in this study.
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