Protein samples were extracted from callus and cell suspensions at different developmental stages of the non-commercial Cotton varieties Coker 312, Coker 100 and Delta Pine 15 (Gossypium hirsutum L.). Proteins were separated by two-dimensional gel electrophoresis (IEF- PAGE-SDS) and silver stained. Gels were analysed with the ImageMaster software (Pharmacia-Biotech). Protein patterns differed with the level of tissue development. In the case of Coker 312, suspension cultures are characterised by a peek in total spot amount, while callus cultures showed abundant proteins in a low range of molecular weight during early embryogenesis.

The aim of the study is to provide a tool for the identification of proteins specific for somatic embryogenesis and regeneration.