A population of wheat and tritordeum transformants showing a high degree of marker gene stability and heritability

The stability and heritability of three marker genes was investigated in a population of twelve independent transgenic cereal lines (six wheat and six tritordeum). Integration patterns, inheritance of structural transgenes and inheritance of expression were analysed in the T₀ and T₁ generations for all 12 lines. Transmission and expression were analysed in the T₂ generation for 9 lines and in the T₃ generation for the six wheat lines. Inheritance of integration patterns was highly stable, and transmission of the transgenes and inheritance of their expression followed Mendelian ratios in the majority of lines. A gradual reduction in uidA expression was observed over three generations, which was not accompanied by a similar reduction in bar expression. Some unexpected phenomena associated with transgene inheritance were also observed and are discussed. Received: 9 February 1999 / Accepted: 11 February 1999