Abstract:
BACKGROUND: Japanese knotweed (Reynoutria japonica var. japonica), a problematic invasive species, has a wide geographical distribution. We have previously shown the potential for attenuated total reflection Fourier-transform infrared (ATR-FTIR) spectroscopy and chemometrics to segregate regional differentiation between Japanese knotweed plants. However, the contribution of environment to spectral differences remains unclear. Herein, the response of Japanese knotweed to varied environmental habitats has been studied. Eight unique growth environments were created by manipulation of the red: far-red light ratio (R: FR), water availability, nitrogen, and micronutrients. Their impacts on plant growth, photosynthetic parameters, and ATR-FTIR spectral profiles, were explored using chemometric techniques, including principal component analysis (PCA), linear discriminant analysis, support vector machines (SVM) and partial least squares regression. Key wavenumbers responsible for spectral differences were identified with PCA loadings, and molecular biomarkers were assigned. Partial least squared regression (PLSR) of spectral absorbance and root water potential (RWP) data was used to create a predictive model for RWP.
RESULTS: Spectra from plants grown in different environments were differentiated using ATR-FTIR spectroscopy coupled with SVM. Biomarkers highlighted through PCA loadings corresponded to several molecules, most commonly cell wall carbohydrates, suggesting that these wavenumbers could be consistent indicators of plant stress across species. R: FR most affected the ATR-FTIR spectra of intact dried leaf material. PLSR prediction of root water potential achieved an R2 of 0.8, supporting the potential use of ATR-FTIR spectrometers as sensors for prediction of plant physiological parameters.
CONCLUSIONS: Japanese knotweed exhibits environmentally induced phenotypes, indicated by measurable differences in their ATR-FTIR spectra. This high environmental plasticity reflected by key biomolecular changes may contribute to its success as an invasive species. Light quality (R: FR) appears critical in defining the growth and spectral response to environment. Cross-species conservation of biomarkers suggest that they could function as indicators of plant-environment interactions including abiotic stress responses and plant health.
摘要:
背景:日本虎杖(Reynoutriajaponicavar。粳稻),有问题的入侵物种,具有广泛的地理分布。我们先前已经证明了衰减全反射傅里叶变换红外(ATR-FTIR)光谱和化学计量学在日本虎杖植物之间隔离区域差异的潜力。然而,环境对光谱差异的贡献尚不清楚。在这里,研究了日本虎杖对各种环境栖息地的响应。通过操纵红色:远红光比(R:FR)创建了八个独特的生长环境,水供应,氮,和微量营养素。它们对植物生长的影响,光合参数,和ATR-FTIR光谱图,使用化学计量学技术进行了探索,包括主成分分析(PCA),线性判别分析,支持向量机(SVM)和偏最小二乘回归。用PCA载荷确定了负责光谱差异的关键波数,和分子生物标志物被分配。光谱吸光度和根水势(RWP)数据的偏最小二乘回归(PLSR)用于创建RWP的预测模型。
结果:使用ATR-FTIR光谱与SVM联用来区分在不同环境中生长的植物的光谱。通过PCA负载突出显示的生物标志物对应于几个分子,最常见的是细胞壁碳水化合物,这表明这些波数可能是跨物种植物胁迫的一致指标。R:FR对完整干燥叶材料的ATR-FTIR光谱影响最大。PLSR预测根水势的R2为0.8,支持ATR-FTIR光谱仪作为预测植物生理参数的传感器的潜在用途。
结论:日本虎杖表现出环境诱导的表型,通过其ATR-FTIR光谱的可测量差异来指示。关键生物分子变化所反映的这种高环境可塑性可能有助于其作为入侵物种的成功。光质(R:FR)在定义对环境的生长和光谱响应方面显得至关重要。生物标志物的跨物种保护表明,它们可以作为植物与环境相互作用的指标,包括非生物胁迫反应和植物健康。