Protecting plant yield is necessary with the emerging challenges in feeding the growing population. However, plant pathogens/diseases damage crop yields in significant amounts annually. Therefore, it is mandatory to rapidly detect plant pathogens and diseases at the early stages to protect crop yields. Conventional plant pathogen and disease detection techniques, such as microscopic and cultural techniques, are complex and slow. Further, immunological and molecular biology techniques suffer with low sensitivity and rapidity. Nanotechnology has become handy in making the aforementioned techniques more versatile due to nanoscale properties. Different types of nanomaterials (0D, 1D, 2D, 3D) can be functionalized to detect plant pathogens and embedded into the plant pathogen detection elements. Once functionalized, these nanostructures can be used as biosensors, nanobarcodes, and imaging tools. These are mainly fabricated using OD nanostructures that are functionalized with antibodies, DNA probes, and specific chemicals that bind with pathogen-specific or disease-specific molecules or compounds. Upon binding, detection will be based on specific color generations or other signaling techniques.