Screening of ornamental plant seeds for Pb tolerance: a preliminary study

• Main Authors: A Majid, Noraishah, Phang, Ing Chia
• Format: Conference or Workshop Item
• Language: English; English
• Published: 2013
• Subjects: Q Science (General)
• Online Access: http://irep.iium.edu.my/34168/4/2013-Osaka-Confernece_Proceedings-1107_Oral.pdf; http://irep.iium.edu.my/34168/1/A_Majid_%26_Phang_2013_-_Presentation_Slides.pdf; http://irep.iium.edu.my/34168/; http://www.nature.com/natureevents/science/events/17089-2013_International_Conference_on_Life_Science_Biological_Engineering
• Institution: Universiti Islam Antarabangsa Malaysia

Introduction: Lead (Pb) is a widespread environmental pollutant that tends to accumulate in soils, raising public and environmental concern. It is highly persistent and non-degradable. Phytoremediation is the preferred method to clean-up metal-contaminated sites, compared to conventional remediation technologies, attributing to its cost-efficient and ecologically safe applications. Ornamental plants, in particular, beautify the landscape. Nevertheless, inhibition of seed germination and retardation of plant growth are the bottleneck for Pb phytoremediation. Objective: This study aims to screen ornamental plant seeds for Pb tolerance, which can be potentially use in the remediation of Pb-contaminated soils. Methods: As a preliminary screening, six types of ornamental plants were used: Bellis perennis, Celosia plumosa, Cosmos bipinnatus, Lavatera arborea, Tagetes patula, and Zinnia pumila. The effects of Pb on seed imbibition and germination, as well as seedling growth were examined. Results: It was found that except C. plumosa, the seed germination rate of the ornamental plants decreased as the the Pb concentration increased. Nevertheless, the seed germination rates of B. perennis, L. arborea, and Z. pumila were higher than 50% despite subjecting to Pb treatments (50, 100 and 200 ppm). As the radicals pierced through the seed coats, Pb toxicity occurred in a concentration-dependent manner. Seedling growth of these ornamental plants was reduced drastically, except L. arborea. The shoot and root length of L. arborea did not seem to be affected by 200 ppm of Pb treatment. Among the tested ornamental plants, L. arborea has the highest Pb tolerance index. Conclusion: In the present study, L. arborea seems to be the most promising plants to be used for Pb phytoremediation.