Non-invasive detection of arsenic-induced changes in lentil seed activity using biospeckle optical coherence tomography

Arsenic contamination poses a significant threat to agricultural productivity, necessitating the development of rapid and non-invasive stress detection methods. This study proposes biospeckle optical coherence tomography (bOCT), a noninvasive imaging technique capable of monitoring dynamic cellular activity, as a reliable tool for detecting arsenic-induced stress in lentil ( Lens culinaris ) seeds. Exposing seeds to 1, 5, and 10 mg/L arsenic concentrations resulted in significant reductions in biospeckle contrasts of 6.5%, 13.6%, and 18.8% within 10 h. These early changes closely correlated with conventional stress markers, including reduced germination viability (coefficient of determination R 2 = 0.92, indicating a strong correlation), impaired seedling growth (R 2 = 0.88), and elevated antioxidant enzyme activities (2.1-2.8 fold increase with probability value p < 0.01, indicating statistical significance). Unlike conventional biochemical and imaging methods, which require 48–72 h to detect reliable stress indicators, bOCT provides a faster, real-time, and nondestructive alternative for monitoring internal biological activity. The sensitivity and temporal resolution of bOCT highlight its potential to transform stress detection practices in agriculture, enabling timely intervention and improved crop management.