PERFORMANCE OF TRANSGENIC PLANTS OF POTATO (SOLANUM-TUBEROSUM CV LAILA) GROWN IN-VITRO, IN GREENHOUSE AND IN A FIELD TRIAL

Effects of transformation, regeneration, and integration of marker gen es, on the performance of transgenic potato (Solanum tuberosum) plants were analysed by examination of the regenerated clones at different c ultivation stages. Twenty out of 55 clones resistant to kanamycin in v itro were further analysed under greenhouse conditions and, finally, t he performance of 4 clones was examined in the field. An enzyme-linked immunosorbent assay (ELISA) was developed to quantify the expression of the marker gene encoded beta-galactosidase. In the field trial, a s ignificant correlation was found between the expression of beta-galact osidase and percent of dry matter of the tubers (r = -0.908, P = 0.033 ). Furthermore, the variation in infection of haulm by Phytophthora in festans was significant among clones (P = 0.001) and accounted for the variation in tuber weight seen among clones (R-2 = 0.95). A good corr elation of the relative tuber yields of r = 0.997 (P = 0.00025) betwee n the greenhouse and the held suggests that greenhouse experiments can be designed which enable the prediction of field performance of trans genic clones.