Figure 1.

The effect of plant age on the dsRNA-induced NPTII downregulation in Arabidopsis thaliana. Quantification the NPTII mRNAs (log₂) in the KA0-1 (a) and KA0-2 (b) lines of A. thaliana in response to foliar application of sterile filtered water (control water treatment) or NPTII-encoding dsRNA (dsRNA treatment) relative to NPTII mRNA level in A. thaliana before treatments. The abaxial and adaxial surfaces of the leaves were treated by sterile soft brushes with 0.35 µg/µL of NPTII-dsRNA or water (100 µL per individual treatment). dsRNA was applied to an individual 4- or 6-week-old plant and to three 2-week-old individuals in an independent experiment. qRT-PCR data are presented as mean ± SE (two independent experiments). *, **—significantly different from the values in plants before treatments at p ≤ 0.05 and 0.01, respectively, according to the Student’s t-test.