MORPHOMETRIC CHARACTERISTICS AND SEED GERMINATION OF Cedrela odorata L.

Abstract

With the objective of identifying the quality of the seed of Cedrela
odorata L. in trees with desirable dasometric variables to be considered
candidates to become parent trees, the seed from 60 trees was
collected in different environments of Chiapas, México, during
February and March 2017. Once the seed was harvested, the research
was carried out in the Laboratory of Forest Seeds from the School of
Agricultural Sciences Campus IV (UNACH). Different variables were
determined according to the rules of the International Seed Testing
Association (ISTA, 2010), 15 days after their collection; the variables
were: weight of 100 seeds (g), percentage of germination and purity,
moisture (CH) and viability (tetrazolium). The essays were established
in a completely random experimental design with three repetitions
of 30 seeds from each tree. The results were graphed with the Sigma
Plot software (ver. 10.0) by Jandel Scientific, and the standard error
was considered as a dispersion measurement in the averages. The
statistical analysis was performed through the GLM software from SAS
version 8.1, and the differences between means according to Tukey
(p?0.05). The results indicated that the most contrasting variables were
the weight of the seed, the percentage of germination and the number
of seeds per kg^-1. The lowest germination of the seeds collected was
found in the physiographic regions: coastal plains close to the littoral.
The ecosystems Sierra Lacandona, South of Chiapas and Coastal Plain
toward the Chiapas Sierra Madre, were suggested as environments to
select parent trees of Cedrela odorata L. with presence of rains all year
long and abundant rains in the summer (3000-3500 mm), temperatures
of 20-28 |C, Leptosol, Cambisol, Regosol and/or Phaeozem soils, and
altitude of 500 to 1000 m.