TITLE:
Estimating Emission of Leaves Seedlings Forest in Different Shading Levels, at Conditions of Transition Amazon-Cerrado, Brazil
AUTHORS:
Emanoeli Borges Monteiro, Cátia Cardoso da Silva, Andréa Carvalho da Silva, Adilson Pacheco de Souza
KEYWORDS:
Vegetative Growth, Thermal Sum, Degree-Days, Statistical Indicatives
JOURNAL NAME:
American Journal of Plant Sciences,
Vol.5 No.15,
July
10,
2014
ABSTRACT: This study
determined the thermal requirements of forest native seedlings (Hymenolobium petraeum and Parkia pendula) and exotic seedlings (Adenanthera pavonina and Cassia fistula) all belonging to
Fabaceae family, in three shading conditions (full sun, 50% and 65% of global
radiation attenuation by poliefinas black screens). Also they were estimated of
leaf emergence by Phyllochron and the Wang and Engel models, on climatological
conditions at Sinop (Region of Transition Amazon-Cerrado), Mato Grosso State,
Brazil, for winter period (between June and August of 2012). The minimum (Tb) and maximum (TB) basal temperatures and
the optimum temperature (Topt)
of growth of each species were estimated by regressions between relative growth
rates and minimum, maximum and average temperatures, respectively. The values
of the estimated Tb were
15.0°C, 16.4°C, 14.5°C and 14.6°C; to TB were 39.7°C, 37.1°C, 38.6°C and 40.1°C; and to Topt were 24.4°C, 24.9°C, 24.9°C and 25.1°C to A. pavonina, C. fistula, H. petraeum and P. pendula, respectively. The Phyllochron
model showed highest efficiency in the estimation of leaf appearance when compared
to Wang and Engel method.