The determination of the molecular composition of plant leaves is essential to assist in nutritional management, whether for cultivated or non-cultivated species. In this sense, the study aimed to apply FTIR technique in combination with chemometrics and ROC analysis for the evaluation of changes in compositional of plant leaves of Physalis angulata and Physalis peruviana due to nitrogen fertilization treatments. Both species were grown under different doses of nitrogen (0, 200, 400, and 600 Kg ha⁻¹) and leaf samples were evaluated using ATR-FTIR. Our results demonstrate that the spectra of both species were influenced by the nitrogen doses. The computed band area from the lipid/amide, lipid/carbohydrates, degree of esterification and calcium oxalate shows nitrogen fertilization due to 400 Kg ha^-1 of N treatment is more effective for a better quality of yield. 2D correlation spectral analysis (2DCOS) reveals cellulose and pectin begins changes followed by amide of proteins due to nitrogen treatment in P. peruviana samples. The P. angulata plants shows hemicellulose changes predominating followed by proteins and polysaccharides. The obtained principle component analysis plot and loading values show the Physalis species samples distinctly separated from control with protein and carbohydrates are predominant in influencing separation among them. Receiver operation characteristic analysis shows a higher value of area under the curve reflecting better reliability of the experiments carried out. Hierarchical cluster analysis shows closed separation for a similar group on dissimilarity scale. Thus the use of 2DCOS coupled with chemometrics helps to identify changes in the composition of leaves of physalis species due to nitrogen doses, constituting a fast and precise measuring for the suitable management of this fertilization.

无论是栽培品种还是非栽培品种，确定植物叶片的分子组成对于协助营养管理都是必不可少的。从这个意义上讲，该研究旨在将FTIR技术与化学计量学和ROC分析相结合，以评估由于施氮处理而导致的酸浆和酸浆的植物叶片组成变化。两种物种均在不同剂量的氮气下生长（0、200、400和600 Kg ha ^-1）和叶片样品使用ATR-FTIR进行评估。我们的结果表明，两种物种的光谱都受到氮剂量的影响。由脂质/酰胺，脂质/碳水化合物，酯化度和草酸钙计算得出的谱带面积显示，由于400 Kg ha ^-1的氮处理，氮肥更为有效，获得了更高的产量。二维相关光谱分析（2DCOS）显示，纤维素酶和果胶开始发生变化，随后由于氮素处理过的葡萄球菌样品中蛋白质的酰胺作用而发生变化。该P.角线植物半纤维素的显示变化为主，随后蛋白质和多糖。所获得的主成分分析图和载荷值显示了空泡与蛋白质和碳水化合物相比，与对照明显分离的两个物种样品是影响它们之间分离的主要因素。接收器工作特性分析显示曲线下的面积值更高，反映出所进行实验的可靠性更高。层次聚类分析显示相似组在相似度范围内的封闭分离。因此，将2DCOS与化学计量学结合使用有助于确定由于氮剂量引起的酸浆叶片组成的变化，从而构成了一种快速，精确的测量方法，以适当控制施肥。