Regeneracjapędów i stopień ploidalności roślin uzyskanychw kulturach in vitro fragmentów walca osiowego haploidalnych łodyg tytoniu

Abstract

The plant material were haploids obtained from anther in vitro cultures of two-way F1 hybrids (BPA × WGL3, WGL3 × BPA, WABPA3 × WGL3, WGL3 × WABPA3, WGL3 × PW834, PW 834 × WGL3), breeding lines (WGL3 and PW834) and cultivar Wiślica, previously obtained as part of a breeding program involving combining resistance to fungal and viral diseases in the tobacco genome. Stem pith fragments of haploids were culturedon Lloyd medium containing 2 mg/l IAA i 2 mg/l kinetin. The assessmentof shoots regeneration of tobacco as well as the degreeof plant ploidy were evaluated using flow cytometer. The efficiencyof regeneration, expressed as the number of shoots per explant,varied and depended on the genetic origin of haploids (F1 hybrid,breeding line, cultivar). The lowest number of regenerated shoots(2.8/explant) were obtained from the breeding line PW834. Poororganogenetic abilities were probably due to the presence of geneticmaterial from Nicotiana alata in the PW834 genome. Thehighest number of regenerated shoots (13.8 i 10.2/explant) wasobtained from haploids of F1 hybrids WGL3 × BPA and cultivarWiślica, respectively. Flow cytometry analysis of regenerants revealedthat, depending on the tobacco form, 59.84 to 89.39% ofthe individuals remained haploids, whereas from 10.61 to 32.99%of the regenerants were doubled haploids. There was also a smallnumber of polyploids. Hybrids WGL3 × WABPA3 proved to bethe best donor of explants for in vitro induction of doubled haploidsand polyploids.