Figure 5.

Effect of the Inhibition of Extracellular Invertase Activity on the Delay of Senescence by Kinetin.

(A) Detached leaves of a transgenic tobacco line expressing the tobacco invertase inhibitor P17A under control of the cytokinin-inducible promoter Lin6 (Lin6:P17A) and wild-type plants (W38) were infiltrated with water containing kinetin at a final concentration of 30 μg/L.

(B) RNA gel blot analysis showing the accumulation of the transcripts for extracellular invertase Ntβfruct1 and the invertase inhibitor P17A in wild-type (W38) and transgenic (Lin6:P17A) plants after 1 and 3 d of treatment with kinetin (K), respectively.

The results have been reproduced in five independent experiments with three independent transgenic lines, and representative results obtained with line NT71-29 are shown.