Abstract

The objective of the study was to develop an efficient method for shoot regeneration of canola (Brassica napus L.) and to compare the regeneration capacity of different explants on MS medium with several combinations of plant growth regulators. The experiments showed that the morphogenetical potential of canola depends on genotype, primary explant, hormonal structure and concentration of nutrient medium. Cotyledons possessed higher regeneration ability in comparison to hypocotyls and roots. The best regeneration capability was exhibited by the cultivar 'Quantum'. Its frequency with cotyledonary explants reached 68.8% on all used media. Addition of 3 mg/l ABA in nutrient medium considerably increased the regeneration frequency. The highest shoot regeneration (100%), however, took place when cotyledonary explants were cultivated on medium, containing 1.0 mg/l NAA, 8.0 mg/l BAP and 3.0 mg/l ABA. Precultivation of explants on callus induction medium did not affect the shoot regeneration frequency. Vitrification of regenerants was promoted by increasing the auxin NAA or cytokinin BAP, and ABA in the nutrient medium.

Key words: Brassica napus, shoot regeneration, cotyledonary explants, nutrient medium, seedlings, vitrification.