Figure 5. Histochemical GUS assay on bombarded and co-cultivated IEs and their respective IE-derived tissues.
a) freshly bombarded Ies;
b) halved-IE 3 days after bombardment showing distinct GUS expression throughout the entire IE with highest expression localised at the meristematic region and areas with actively dividing cells;
c) germinating IEs with distinct shoot (sh) and haustarium (h);
d) freshly co-cultivated Ies;
e) halved-IE 7 days after co-cultivation showing distinct GUS expression localised at meristematic region and areas with actively dividing cells;
f) callusing IE 2 weeks after co-cultivation;
g-h) callusing assay, with callus developing on IE-derived tissues expressing gus activity;
i) callus developing from roots of plantlets undergoing callusing assay also showing gus activity;
j) leaf tissues from IE-derived plantlets showing gus activity. Blue coloration of tissues indicates the expression of GUS gene substantiating successful gene transfer.