Crop disease is one of the important factors that affect and restrict the development of agricultural production. How to accurately detect the cause and degree of crop disease, and realize scientific early warning and precise prevention of crop disease is particularly important. This paper firstly introduced the types of crop diseases, and then compared and analyzed the advantages and disadvantages of the biochemical detection technologies commonly used for crop diseases, such as molecular biology, immunology, and optical sensing detection technologies, and such as visible image, near infrared spectroscopy, infrared thermal imaging, hyperspectral imaging, etc. from the detection principle and mechanism. Through summing up, it was found that the difficulties of biochemical detection technology mainly included a large workload and a long cycle of detection and identification of a single target pathogen. The difficulty of optical detection technology included easy to be affected by the environment, the presence of foreign bodies in the same spectrum, etc. Finally, the future development direction of optical sensing technology in crop disease detection is given to provide a more comprehensive and systematic reference for related research.

作物病害是影响和制约农业生产发展的重要因素之一，如何准确检测作物病因及病害程度，实现作物病害科学预警、精准防治尤为重要。通过对作物病害类型进行简介，从检测原理和机制对比分析作物病害常用的生化检测技术，如分子生物学、免疫学等技术及光学传感检测技术中的可见光图像、近红外光谱、红外热成像、高光谱成像等技术的优缺点。归纳总结发现生化检测技术的难点，主要包括对单一目标病原物检测、鉴定病原物工作量大、周期长；光学检测技术的难点主要包括易受环境影响、存在同谱异物现象等。针对光学传感技术在作物病害检测中存在的问题给出未来的发展方向，为相关研究提供更全面系统的参考。