Micropropagation of sterile and non-flowering Nicotiana lines

Abstract

Micropropagation could be a useful option to multiply important seeds sterile genetic stocks in crop plants. Nineteen exotic germplasm lines belonging to Nicotiana tabacum, five wild Nicotiana species and two species hybrids that did not flower and/or set seed were micropropagated in vitro through direct organogenesis using leaf expiants. The plantlets thus generated were transferred to pots after hardening. All the transferred plants in germplasm accessions viz., T16, T22, T23, T26, T27, T28, T29, T30/HG, BRK 1, BRK 2, BRK 3, KRK 1, KRK 6, KRK-8, K34, K35 (T35), K36, K37 and K40 found to be male sterile. Inter subgeneric hybrid of N. gossei x N. glauca produced sterile flowers. N. sylvestris, and N. tomentosiformis plants flowered and produced seed, while N. arentsii, N. benavidesii and N. bonariensis plants did not flower. Thus direct organogenesis found to be useful for the in vitro multiplication of rare genotypes in genus Nicotiana. One among the twenty clones of N. excelsior x N. plumbaginifolia hybrid transferred was found to be fertile and set seed. The progeny of fertile hybrid were all fertile. Fertility restoration in N. excelsior-plumbaginifolia hybrid found to be due to chromosome loss and doubling in one of the hybrid cell under tissue culture and its regeneration. Though the chromosomal change observed in the study is useful one, it suggested that care necessary to avoid such changes in other cases. © 2008 The Japan Mendel Society.