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Microsporogenesis in two alloplasmic isonuclear strains of tobacco Nicotiana tabacum L. cv.Zamojska 4 with the cytoplasms of N.knightiana Goodspeed and N.raimondi Macbride

100%

Berbec A.

Genetica Polonica

1994

tom 35

nr 1-2

23-31

Cytology and fertility of viable hybrids of Nicotiana tabacum L. cv. TB-566 with N. alata Link et Otto

63%

Laskowska D. , Berbec A.

Journal of Applied Genetics

2005

tom 46

nr 1

11-18

A vigorous hybrid (N. tabacum cv. TB-566 tetra ? N. alata) ? N. alata was obtained by backcrossing a partly viable sesquidiploid hybrid N. tabacum cv. TB-566 tetra ? N. alata to N. alata. The hybrid was a 35-chromosome near-amphihaploid with a pair of N. alata chromosomes in disomic condition. It was completely self- and cross-sterile and formed from 7 to 8 bivalents in pollen mother cells. By using stem pith culture, polyploidized regenerants were obtained from the 35-chromosome hybrid with somatic chromosome numbers from 65 to 70. These regenerants showed fairly regular meiosis with the number of bivalents in pollen mother cells ranging from 27.3 to 30.4. Irregularities in meiosis included a high number of univalents, aberrant tetrads, and a high frequency of micronuclei. The percentage of acetocarmine-stainable pollen ranged from 22.1 to 78.4. A 66-chromosome regenerant showed fairly regular meiosis and was self-fertile but could not be backcrossed to N. tabacum. This barrier seems to be caused by genic imbalance rather than irregularities of meiotic divisions. Hence transfer programs based on the introgression of entire linkage groups (sexual and somatic hybridization) seem to be of little use in the case of that species.

Cytological investigations of the interspecific hybrids of Nicotiana tabacum L. ? N. glauca Grah.

63%

Trojak-Goluch A. , Berbec A.

Journal of Applied Genetics

2003

tom 44

nr 1

45-54

Interspecific amphihaploid and amphidiploid hybrids between Nicotiana glauca Grah. (2n = 24) and N. tabacum L. (2n = 48) cultivars BY 103 and K 326 were analysed. F1 amphihaploids (2n = 36) were viable and completely self- and cross-sterile, and mostly univalents were present during meiosis (with pairing range from 0 to 5). In some meiocytes, meiotic irregularities were observed, such as sporadic chromatin bridges and formation of restitution nuclei. The resultant F1 hybrids were easily converted to amphidiploids (2n = 72) via colchicine treatment of seedlings. The number of univalents and the frequency of PMCs containing unpaired chromosomes indicated that amphidiploids N. tabacum cv. BY 103 or K 326 ? N. glauca represented quite a high pairing category. However, they were male sterile because pollen mother cells were arrested at the tetrad stage. The termination of development of PMCs, and consequently male sterility, are very rare in this kind of tobacco hybrids.

Androgenetic haploid plants by culturing anthers of alloplasmic strais of tobacco Nicotiana tabacum L. cv.Zamojska 4 with the cytoplasm of N.knightiana Goodspeed and N.raimondii Macbride

63%

Berbec A. , Laskowska D.

Genetica Polonica

1994

tom 35

nr 1-2

33-41