Author/Editor     Jakše, M; Bohanec, B; Ihan, A
Title     Effect of media components on the gynogenic regeneration of onion (Allium cepa L.) cultivars and analysis of regenerants
Type     članek
Source     Plant Cell Rep
Vol. and No.     Letnik 15
Publication year     1996
Volume     str. 934-8
Language     eng
Abstract     Two separate experiments were performed to analyze the effects of different media on gynogenic regeneration in four onion cultivars. In a two step flower/ovary culture procedure, 2,4-dichlorophenoxyacetic acid added to the induction medium was superior to phenylacetic acid in the highly regenerating cultivar, while the effect of thidiayuron in the regeneration medium was generally optimal in higher (2 mg/1) rather than in lower (0.2 mg/1) concentrations. Gellan-gum was compared to agar solidified media. A higher number of regenerants was achieved on the former, but an undesirable hyperhudricity of regenerants formed on gellan-gum solidified media greatly reduced the final survival of formed embryos. Analysis of the time interval needed for regeneration showed high variability (from 46 to 152 days after inoculation), which was particularly pronounced in genetypes with lower regeneration capacity. Simpler isozyme patterns of regenerants showed that all analysed regenerants of the cultivar with a high regeneration capacity were homozygous, while in the other three cultivars, a considerable percebtage (11.1 to 36.4%) of heterozygous regenerants were also detected. Ploidy analysis of the regenerants with simpler isozyme patterns revealed that the majority of lines remain haploid. Identification of 2 homozygous triploid regenerants demonstrated that as in androgenesis, nuclear fusions can occur during gynogenic haploid regeneration.
Descriptors     ALLIUM
REGENERATION
SEEDS
CULTURE MEDIA
FLOW CYTOMETRY
TISSUE CULTURE