This article overviews the major diseases affecting tomato plants (Solanum lycopersicum), caused by viral, bacterial, and phytopathogenic microorganisms. Pathogenic microorganisms parasitising tomato plants lead to significant crop losses in agricultural production, reducing the quality of the produce. The study aimed to investigate the impact of microorganisms on tomato plants, the extent of their harmful effects, and methods of controlling disease pathogens. It has been established that the primary diseases of tomato plants are caused by fungi of the genera Fusarium (fusarium wilt), Phytophthora (late blight), Botrytis (grey mould), and Alternaria (early blight); viruses such as tomato spotted wilt virus and tomato yellow leaf curl virus; and bacteria such as Ascochyta cucumis (bacterial canker of tomatoes) and Xanthomonas vesicatoria (bacterial spot). Agricultural chemicals are recognised as an essential component in pest and disease management, and the primary means of combating plant diseases include chemical substances such as prochloraz, thiabendazole, propiconazole, carbendazim, benomyl, thiophanate, fuberidazole, and others. Systemic fungicides are crucial in controlling various diseases and exhibit beneficial physiological or growth-stimulating effects on plants, including delaying leaf senescence and increasing chlorophyll content. It has been observed that fungicides (chemical groups: strobilurin and carboxamide) are effective in combating early blight, while the primary strategy for controlling grey mould involves chemical management through the use of synthetic fungicides such as quinone inhibitors, benzimidazoles, carbamates, phenylpyrroles, and succinate dehydrogenase inhibitors. Reviewing diseases and chemical control methods for pathogens is highly valuable for agricultural applications. The practical significance of this research lies in its ability to help agricultural producers manage their crops effectively and maintain fruit quality. Knowledge of the major diseases affecting tomatoes enables the timely identification of symptoms and the implementation of appropriate preventive and treatment measures
