Peas, a pivotal cool-season vegetable crop, are cultivated globally and serve as a vital protein and fiber source for a substantial population, particularly among those who adhere to a vegetarian diet. The cultivation of this particular crop encounters several challenges, notably pests and pathogens, which act as formidable barriers to success. Amidst the array of challenges inherent in the cultivation of this plant, the foremost impediment is posed by the root-knot gall nematode. Operating discreetly, this nematode proves to be a major contributor to substantial losses by surreptitiously causing the demise of the plant. In order to elucidate the fundamental causes of this specific disease and mitigate ongoing crop losses, it is imperative to conduct an exhaustive examination of nematode-infested pea plants, employing both elementary and molecular analytical methodologies. In this work, we employed the aforementioned methods in conjunction with optical microscopy to identify the factors contributing to significant crop losses resulting from nematode infections in pea-root plants. The confirmation of nematodes and other microbes in the samples of pea-root plants was achieved through the application of optical microscopy. FTIR and UV-Vis spectroscopy were used to investigate structural changes in the complex compounds of both infected and healthy pea-root plant samples, while WDXRF and LIBS were used to obtain the elemental profiles of these samples.LIBS in combination with k-nearest neighbors (KNN) modeling was also used to discriminate between healthy and nematode-infested pea root samples using the interclass distance approach in order to evaluate the discriminative abilities of sixteen LIBS emission peaks. The method is shown to be a cost-effective and time-efficient alternative to traditional elemental analysis techniques, offering rapid field analysis with minimal sample preparation