[26p-E204-1~13] 3.4 Biomedical optics

▼ [26p-E204-10] Optical coherence tomography detection and quantitative evaluation method to examine the effect of polyethylene microplastics (PEMPs) on lentil seed germination

〇(D)sanath De silva^1,2, Uma Maheswari Rajagopalan³, Li Danyang¹, Hirofumi Kadono¹ (1.Graduate School of Science and Engineering, Saitama Univ., Japan, 2.Dept. of Mechanical and Manufacturing, Univ. of Ruhuna, Sri Lanka, 3.Dept. Mech, Eng. Faculty of Engineering. Shibaura Institute of Technology, Japan)

Keywords:Lentil Seed Germination, Biospeckle Optical Coherence Tomography (bOCT), Polyethylene Microplastics

Microplastics (MPs) are accumulated in the environment at an alarming rate giving a considerable impact on seed germination because of overwhelming usage and mismanagement of plastic. Depending on the formation, MPs can be categorized into two groups, namely primary and secondary MPs. The adverse effect of MPs on seed germination and plant growth have been reported. According to the existing literature, PEMPs could reduce the seed germination rate and seedlings growth. The effect was measured using conventional measurements such as germination test, root length, and leaf length. In general, the effect of external stressors on seed germination and seedling growth are assessed by destructive post-harvesting conventional measurements such as germination test, cold test, tetrazolium test, etc., that require a relatively long period of time. Hence, there is an urgent requirement for novel methods that can monitor the effect of MPs on seed germination and seedling growth at an early stage. Here, we proposed the Biospeckle Optical Coherence Tomography (bOCT), to observe the effect of polyethylene microplastics (PEMPs) on lentil (Lens culinaris) seed germination and seedling growth. bOCT is an ultra-high accurate non-contact, non-destructive, in vivo monitoring technique to visualize the change of internal activity of a biological object. Furthermore, conventional measurements such as seed germination rate, root length, shoot length, fresh and dry weight of seedlings were also measured for comparison with bOCT results. The bOCT results show that the tested PEMPs concentrations has negative influence on seed germination with a clear reduction of the internal activity of seed observed just after 6h of exposure. Hence, the proposed method is able to observe the effect of PEMPs at an early stage before the germination.