Comparison of Growth and Leaf Color Quality of <italic>Mesembryanthemum cordifolium</italic> f. <italic>variegata</italic> as Affected by Shading Levels

Abstract

Background and objective: Mesembryanthemum cordifolium is a plant belonging to the Aizoaceae family and is native to South Africa and Namibia. As a CAM plant, M. cordifolium exhibits strong resistance to drought stress and can be utilized for the removal of soil salinity and heavy metals. Furthermore, it is an important medicinal crop with anti-inflammatory and antidepressant effects. However, despite its potential benefits, research on the optimal growth environment for M. cordifolium remains scarce.Methods: Therefore, this study selected M. cordifolium f. variegata with high ornamental value as the experimental plant and compared the effects of different shading levels on the growth and leaf color quality of variegated baby sun rose (M. cordifolium f. variegata). Six shading levels (0, 35, 45, 60, 75, and 99%, respectively) were designed using polyethylene (PE) shading films.Results: The results showed that the shoot height, shoot width, dry weight, and chlorophyll content (SPAD units) were highest under the 60% shading level, while leaf length, leaf width, and fresh weight were highest under the 75% shading level. On the other hand, growth was relatively lower under the 0% shading level, which suggests that M. cordifolium f. variegata prefers shade over direct sunlight. On the contrary, M. cordifolium f. variegata showed growth even under the 99% shading level, proving to have strong shade tolerance, but the leaf color quality was lowerst.Conclusion: In conclusion, to significantly increase the size and biomass of plants and improve leaf color quality when cultivating M. cordifolium f. variegata under shading treatment, it is recommended to cultivate it under 60-75% shading levels.