Figure 7. Average of GUS activity for root, stem and leaf of tobacco trangenic plants. Six independent transgenic tobacco plants harboring each of the three constructs were used to determine the average of GUS activity in root, stem and leaf. Shadowed, white and black bars are the average of GUS activity for plants harboring 0.267 kb of promoter size, 1.306 kb of promoter and 2.59 kb, respectively. Lines in bars are indicating the standard deviation. Both average and standard deviation values were calculated by transforming back the square root transformed data used in the statistical analysis. Root and leaf values are statistically significant (p<0.05). GUS activity for the contructs including 1.306 kb and 2.59 kb of promoter size showed significant differences when comparing root with leaf and stem. For the construct including 0.267 kb of promoter size, statistical analysis did not detect differences (p>0.05).