Plant Pathology Science

Many plant pathogens can spread into irrigation water in farms, gardens or greenhouses and cause disease in various crops. So far, a large number of plant pathogens including 43 fungal-like organisms, 27 fungi, eight bacteria, 26 viruses and 13 nematodes have been isolated and reported from water sources and water transmission systems. In many greenhouses, various pesticides are used to prevent the spread and control of these pathogens, which imposes costs, soil or water pollution, and the possibility of resistance in pathogens. Different methods of water treatment to control aquatic pathogens in the irrigation system using chemicals such as chlorine, chlorine dioxide, copper, silver and ozone, physical methods such as water filtration, heat, ultraviolet rays and the use of biosurfactants such as rhamnolipid and  nitrapyrin, are described in this article.

Plant viruses cause major losses to agricultural crops worldwide. Plants react to the virus infections via several defense mechanisms, such as ubiquitination. Ubiquitin (Ub) and ubiquitin proteasome system (UPS) play key role in the function modification and degradation of proteins in plants. Ub attachment to the cellular proteins alters the stability, the cellular establishment or activity of the target protein. The key role of UPS has been revealed in defense mechanisms and other plant processes. Viruses as obligate intracellular parasites have evolved mechanisms to interfere UPS. In some cases, it has been shown that viral proteins were targeted by this system. Ubiquitination plays an important role in plant–virus interaction which can lead to plant resistance or pathogenicity in the host plant. Therefore, further understanding of UPS and its role in plant-virus interaction can develop novel methods to increase resistance to viral infections in plants.