Abstract
The genus Eucalypts includes the most widely used tree species, such as E.globulus, for industrial plantation, mainly for making pulp and paper. However, E.globulus is difficult to vegetatively propagate.
In this study, we investigated the effect of CO2 on adventitious root formation. Eleavated CO2 concentration (1000 ppm) increased rooting rate, root length and number of roots compared with atmospheric CO2 (380 ppm). We examined the expression of small subunit of ribulose 1,5-bisphosphate carboxylase (RBCS ) after elevated CO2 concentration. The expression of RBCS was induced after 2 d in high CO2 treatment. These results suggest that increased rate of photosynthesis is responsible for the increase in root growth. Furthermore, adventitious root emergence and development were significantly inhibited in NPA (N-1-naphthylphalamic acid, an auxin transport inhibitor)-treated E.globulus. This data supports the hypothesis that a polar transport of the auxin is critical for the induction of adventitious roots.
