Somatic hybridization in nicotiana spp segregation of organellar traits among hybrid and cybrid plants
Glimelius, K.; Chen, K.; Bonnett, H.T.
Planta (Heidelberg) 153(6): 504-510
ISSN/ISBN: 0032-0935 Accession: 006437504
Protoplasts from a nitrate reductase-deficient mutant of N. tabacum L. were fused with protoplasts from a stamen-less, cytoplasmically male-sterile cultivar of tobacco [(Burley 21)] containing the cytoplasm from N. suaveolens Lehm. Plants were regenerated from the fused protoplasts and characterized with respect to stamen development, chromosome number and chloroplast composition. Of 29 regenerated plants, stamen production was restored in 26 plants and pollen production in 22. One plant was male sterile, and 2 plants have never flowered. Analysis of the electrophoretic mobility of ribulose-1,5-bis-phosphate carboxylase (RuBPcase) showed that 19 of the plants contained RuBPcase of the N. suaveolens type, 6 plants contained enzyme of the N. tabacum type, and 4 plants contained both types. Analysis of resistance to tentoxin in seedlings from 20 of the plants demonstrated that 14 had N. suaveolens-type chloroplasts, 3 had N. tabacum type, and 3 contained both types. Many of the plants which produced stamens and pollen still contained chloroplasts of the N. suaveolens type. Thus, the trait of cytoplasmic male sterility in tobacco is not an expression of the type of chloroplast genetic material.