The utilization of physical protectors has been considered an efficient technique for direct sowing of
different species, mainly native ones. Based on the importance of the species
Peltophorum dubium
for
revegetation of degraded areas, tree planting and landscaping, this study evaluated gas exchanges in
canafistula seedlings under the influence of physical protectors subjected to different luminosity rates. The
experiment was carried out in pots a Dystropheric Red Latosol, a typical soil of the study region. Seedlings
of
Peltophorum dubium were evaluated at 30, 50, 70, 90, 110, and 130 days after sowing (DAS). Thus,
the following treatments were adopted: T1, absence of physical protector (APP); T2, transparent physical
protector (TPP); T3, transparent physical protector + blue cellophane (BPP) and T4, transparent physicalprotector + red cellophane (RPP). The evaluated characteristics were: stomatal conductance, transpiration,
CO
2 assimilation, CO
2 concentration inside the substomatal chamber and water use efficiency. In general,
all types of physical protectors led to higher mean values of gas exchanges during their permanence in the
sowing site until 70 DAS, except for CO
2 assimilation. However, water use efficiency was higher in APP
seedlings at the same period.
