Callus induction and plant regeneration by Brazilian new elite wheat genotypes

Abstract

The distinction of genotypes responsive to tissue culture and the development of an efficient regenerationsystem are the first steps towards transgenic plant production. Nine Brazilian wheat (Triticum aestivum L.) genotypes werecultivated in vitro to evaluate the embryogenetic capacity. The explants (immature zygotic embryos) were tested in twodifferent culture media, MS (Murashige and Skoog 1962) and modified MS - MMS (Zhou et al. 1995) with decreasing dosagesof hormone regulators. Three distinct phases were observed in each medium: induction, maintenance and regeneration. Afterinduction, the somatic embryogenesis of calli was evaluated every 21 days. Genotypes responded differently to the differentculture media. The embryogenic response of genotype CD104 was best in both culture media tested. On MMS, the values ofcallus induction, plant regeneration and ratio of regenerated plantlets per rescued embryo of this genotype were 100%, 99.5%and 1.1%, respectively. Genotypes CD104, CD200126 and CDFAPA 2001129 were most responsive on MS (regenerationcapacity of 37.5%, 33.5% and 33% respectively), and therefore interesting for genetic transformation in plant breedingprograms that develop new elite cultivars with a commercial purpose.

Keywords

• Wheat
• Triticum aestivum
• callus induction
• plant regeneration
• culture medium
• embryogenesis.