Callus formation and plant regeneration from immature and mature embryos of rye (Secale cereale L.)

Abstract

An efficient protocol was developed to regenerate entire plants from immature embryos of elite genotypes of rye as a prerequisite to plant transformation. Three winter genotypes and one spring genotype were tested using both immature and mature embryos as explants. Four types of callus initiation media and five kinds of regeneration media were tested in all possible combinations. Immature embryos gave much higher levels of plant regeneration than mature embryos, but mature embryos could be induced to regenerate plants for all genotypes and media tested, although at low levels. A minimum stage of embryo development must be reached before embryos can be cultured successfully. Genotypic effects were less pronounced than those reported for inbred cereal species such as wheat and barley, but there was an effect of genotype on percentage of callus formation. There was a significant interaction between genotype and initiation media. Composition of the initiation media affected both the percentage of callus formation from embryos and subsequent frequencies of plant regeneration. Composition of the regeneration media had no effect on level of plant regeneration. Immature embryos of all genotypes tested could be induced to produce 90±100% callus on appropriate initiation media and all regenerated shoots from approximately one-half to three-quarters of the calluses produced.

Development of an embryogenic callus induction method for centipede grass (Eremochloa ophiuroides Munro) and subsequent plant regeneration

“…The use of growth regulators for in vitro regeneration has been extensively studied in grass and cereal tissue culture (Ward and Jordan 2001). The role of auxin (2,4-D) for induction of somatic embryogenesis is common in grasses and cereals, with optimum concentrations varying between different grass species studied (Wang et al 2001).…”

High-frequency plant regeneration through callus initiation from mature embryos of maize ( Zea Mays L.)

“…This is probably due to the fact that each shoot on embryogenic callus was not removed immediately as it formed. As Ward and Jordan (2001) reported, our study also sought to develop a method where plantlets could be regenerated directly on the callus. This minimizes the amount of time in culture, which can be important for minimizing somaclonal variation.…”

“…Plant regeneration has previously been achieved from callus cultures from mature embryos in cereals (Rueb et al 1994;Özgen et al 1998;Akula et al 1999;Ward and Jordan 2001). The use of mature embryos from dry seeds has several advantages: mature embryos are easy to handle, available year round and in bulk quantities.…”

Effect of Silver Nitrate and Amino Acids on High Frequency Plants Regeneration in Barley (Hordeum vulgare L.)

“…species or cultivars (Bregitzer 1992). Moreover, callus quality varied considerably among genotypes (Vasil andVasil 1987, Islam 2010); and most barley varieties initiate friable and translucent callus (Hanzel et al 1985, Ward and Jordan 2001, Chauhan and Kothari 2004. Bregitzer et al (1998) also reported that the poor regeneration potential of modern cultivars is one current limitation of barley transformation.…”