The extraction of mineral resources from mines plays a vital role in global socio-economic development. However, acid mine drainage (AMD) has been one of the major pollutants, and a vast area of the agricultural fields has been polluted. Therefore, techniques for monitoring the response of plants to AMD that arise during mineral extraction are necessary. In addition, such a technique becomes especially valuable to understand how the plants could play a role in the phytoremediation of AMD. We propose the use of biospeckle Optical Coherence Tomography (bOCT) to investigate the response of Kaiware daikon seeds under the exposure to simulated AMD at two different concentrations of 40 mL/L and 80 mL/L. OCT images of the Kaiware daikon seed were obtained at a speed of 10 frames per second (1 frame: 512 × 2048 pixels) for a few tens of seconds. For each pixel of the OCT structural images, the contrast across the temporal axis was calculated to give biospeckle contrast OCT images (bOCT images). It was found that bOCT images clearly distinguished the changes due to 40 mL/L and 80 mL/L of AMD treatments from the control within a short time of around an hour, compared to the conventional OCT images that failed to show any changes. This variation was found to be statistically significant and could reflect the internal activity of the seeds. The proposed bOCT method could be a rapid, non-invasive technique for screening suitable plants in AMD phytoremediation applications.

Forsythia suspensa (Thunb.) Vahl, a pharmacopoeial medicinal plant, is valued for its therapeutic efficacy in heat-clearing detoxification, dispelling wind-heat, and promoting blood circulation to resolve stasis. Flavonoids, ubiquitous secondary metabolites in F. suspensa, are critically linked to pharmacological activities and exhibit diverse biological functions. To elucidate the chemotypic divergence and ecological drivers of its bioactive compounds, we conducted flavonoid metabolomic profiling across ten wild populations F. suspensa using UPLC-MS/MS. Results revealed significant inter-population variation in all twenty-nine flavonoid metabolites analyzed. Notably, Notably, Cinchonain Ic was significantly enriched in the JX population, Flavanomarein in the LT population, and Desmethylxanthohumol in the HX population. Association analysis with environmental variables further indicated that Sulfuretin, Apigenin-5-O-glucoside, and Flavanomarein were positively correlated with multiple precipitation-related variables (bio12-Annual Precipitation, bio14-Precipitation of Driest Month, bio17-Precipitation of Driest Month, and bio19-Precipitation of Coldest Quarter), whereas Vicenin 2 was negatively correlated with bio12, bio17, and bio19. Homoplantaginin showed a positive correlation with bio4 (Temperature Seasonality) and bio7 (Temperature Annual Range). Loureirin B was positively correlated with elevation but negatively correlated with high-temperature variables (bio5-Max Temperature of Warmest Month, bio8-Mean Temperature of Wettest Quarter, and bio10-Mean Temperature of Warmest Quarter). 5-Demethoxynobiletin was positively associated with both precipitation (bio12, bio17, bio19) and temperature variables (bio1-Annual Mean Temperature, bio6-Min Temperature of Coldest Month, bio9-Mean Temperature of Driest Quarter and bio11-Mean Temperature of Coldest Quarter). Cinchonain Ic was positively correlated with bio2 (Mean Monthly Temperature Range), and Oroxin A was negatively correlated with elevation. These findings demonstrated that flavonoids accumulation in F. suspensa was predominantly influenced by temperature heterogeneity, with precipitation serving as a secondary factor, while latitude and elevation play only limited roles. This study systematically investigates the divergence and environmental drivers of flavonoids in F. suspensa populations, clarifies the molecular ecological basis of its adaptation to environmental heterogeneity, and provides valuable insights for leveraging ecological factors to enhance medicinal potential, ultimately supporting targeted breeding and optimized field management strategies.

Acid mine drainage is a serious environmental problem faced by the mining industry globally, causing the contamination of numerous agricultural lands and crops. Against this background, this study aims to investigate the effects of AMD on soybean, one of the major crops. To monitor the effects of AMD on soybean quickly and non-destructively, we have proposed a technique called biospeckle optical coherence tomography (bOCT). Soaked soybean seeds were monitored by bOCT, once after 6 h and again after germination, i.e., 48 h, and the results were compared with conventional parameters such as enzyme activity, iron uptake, and seedling length. It was found that bOCT could detect the effects due to the AMD after just 6 h with a decrease in a parameter called bisopeckle contrast that reflects the internal activity of the seeds. On the other hand, the conventional parameters required a week for the effects to appear, and the results from bOCT after six hours were consistent with those obtained by conventional measures. Because of the non-invasive nature of bOCT, requiring only tens of seconds of measurement with an intact, it has not only the potential to screen but could also constantly monitor long-term changes, thus possibly contributing to the study of the effects of AMD on crops.