Callus induction and plant regeneration by Brazilian new elite wheat genotypes

E.C.G Vendruscolo,I Schuster,C.A Scapim,E.S Negra

doi:10.12702/1984-7033.v08n03a03

Abstract

The distinction of genotypes responsive to tissue culture and the development of an efficient regeneration system are the first steps towards transgenic plant production. Nine Brazilian wheat (Triticum aestivum L.) genotypes were cultivated in vitro to evaluate the embryogenetic capacity. The explants (immature zygotic embryos) were tested in two different culture media, MS (Murashige and Skoog 1962) and modified MS - MMS (Zhou et al. 1995) with decreasing dosages of hormone regulators. Three distinct phases were observed in each medium: induction, maintenance and regeneration. After induction, the somatic embryogenesis of calli was evaluated every 21 days. Genotypes responded differently to the different culture media. The embryogenic response of genotype CD104 was best in both culture media tested. On MMS, the values of callus 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 (regeneration capacity of 37.5%, 33.5% and 33% respectively), and therefore interesting for genetic transformation in plant breeding programs that develop new elite cultivars with a commercial purpose.

Highlights

Genetic engineering of any species depends on the development of efficient and reliable callus induction and plant regeneration systems
The use of elite wheat cultivars as exogenous gene recipients can speed up the process of commercial field applications of transgenic wheat
Callus induction and growth from immature embryos was visible in both media and in all genotypes after 6-10 days in the dark

Summary

Introduction

Genetic engineering of any species depends on the development of efficient and reliable callus induction and plant regeneration systems. The use of elite wheat cultivars as exogenous gene recipients can speed up the process of commercial field applications of transgenic wheat. It is seldom known which elite cultivars have a good level of tissue culture response (TCR). Several authors have studied TCR of elite wheat cultivars in European (Pastori et al 2001); Asian (Arzani and Mirodjagh 1999, Wu et al 2002, Li et al 2003), Mexican (Fennell et al 1996); Australian (Witrzens et al 1998), and Chinese genotypes (Tang et al 2006). Few papers were found in the literature dealing with the regeneration performance of Brazilian genotypes (Dornelles et al 1997)

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Results