Abstract

PINA, Margarito  and  ARBOLEDA, María Elena. Effect of two light environments on the initial growth and quality of Crescentia cujete. Bioagro [online]. 2010, vol.22, n.1, pp.61-66. ISSN 1316-3361.

Crescentia cujete is a small, deep rooted native plant whose architecture, flowers and ornamental fruit makes it suitable for urban tree, in addition to its use in traditional medicine and handicrafts. The plant is well adapted to semi-arid conditions The objective of this study was to evaluate the effect of two light environments (light and shade) on the initial growth and quality of C. cujete plants. The mean maximum ligth intensity at midday was 1170 µmol·m^-2·s^{-1 in the lighted treatment and 280 µmol·m-2}·s^-1 under the shade. Seedlings with two pairs of true leaves were transplanted into containers and placed under the two environments. Six months later, shade plants were taller and with less stem diameter, with larger leaves and higher chlorophyll content. Total accumulation of biomass did not differ between treatments, but the assimilated distribution was higher toward the leaf component under shade conditions and higher toward the roots under the lighted treatment. The leaf to root biomass ratio under shade doubled the average obtained under light. Although in both environments the quality indexes were acceptable, the plants that grew at 1170 µmol. m^-2.s^-1 showed higher quality. This species developed morphological and physiological plasticity that allowed it to adapt to both light environments.

Keywords : Light intensity; shading; ornamental plants; quality index.