FIG. 2.

DGGE profiles of bacterial rhizosphere communities of young potato plants (first year; field L). Each lane represents a rhizosphere sample from one field plot generated by amplification of 16S rRNA gene fragments with bacterium-specific primers from rhizosphere DNA and electrophoretic separation of the PCR products in a denaturing gradient (insufficient PCR product was obtained from two samples). DL4 and DL5, T4 lysozyme-expressing cultivars; DES and DC1, control cultivars without the T4 lysozyme gene; M, standard with fragments a to k (see Materials and Methods).