Effects of shading on some morphological and physiological characteristics of Begonia semperflorens

摘要

Potted Begonia semperflorens were exposed to different levels of shading (25%, 50%, 75%, 87%, and 93%) to investigate the response of the morphological and physiological characteristics of this plant. Results revealed that, as the level of shading increased, the leaf area, water content, superoxide anion (O 2 ·- ) production rate, malondialdehyde (MDA) content and plasma membrane permeability exhibited increasing trends when compared with natural light. By contrast, the relative contents of anthocyanin, soluble sugar, starch and the superoxide dismutase (SOD) activity displayed decreasing trends. However, number of flowers per plant, chlorophyll content, nitrate reductase (NR), and peroxidase (POD) activities initially increased but subsequently decreased. Comprehensive analysis indicated that different light intensities exerted different degrees of influence on the morphological characteristics, ornamental quality and physiological characteristics of B. semperflorens . This plant can adapt from full illumination to 87% shading, and the number of flowers increased under 25–75% shading, at which the best ornamental quality was also observed.