The present work aimed to accomplish the histological analysis of the events involved in the adventitious
rooting pattern of four
Eucalyptus grandis
x Eucalyptus urophylla
clones. The mini-cuttings were collected
from a mini-stump and the rooting experiments were set up under mini-hedge indoor semi-hydroponics
by means of intermittent flooding fertirrigation. For histological analyses, the proximal ends of the minicuttings
were collected after 0, 1, 2, 4, 6, 8, 10, and 12 days after planting them at greenhouse. After fixation
with FAA
70%, the samples were dehydrated in a graded ethanol series and infiltrated overnight in metracrilate
resin, and finally embedded in resin. It was verified the endogenous origin of adventitious root primordia
from vascular cambium, and in some cases, the formation and proliferation of
calli at the proximal end of
the mini-cuttings within 8 to 12 days.