The aim of this paper is to acquaint the problem of phytosanitary threats in the context of crop irrigation. This paper shows a series of reports that refer to the problem of pathogens spread through irrigation and irrigation systems. Irrigation may influence directly or indirectly the plants health condition. It may affect the conditions in which the infection may occur, but also create conditions that promote fungal sporulation and overall spread of the pathogen. Irrigation favors the plants growth, which vegetative mass is more developed, lush, but at the same time the tissue covering the plant is more sensitive towards any infection. A more intense plant growth affects the density which favors the occurrence of many diseases. In general irrigation may cause a negative or positive affect or may not influence the crops at all. In this paper, we also take point out the problem of irrigation water quality which may be the main source of infection of pathogens that could belong to various taxonomic units. To the most predominating phytopathogens in irrigation water we may include the Phytophthora and Pythium genus. Irrigation water may also contribute to the occurrence of many viruses and fungi. In order to limit the ...