|Potato (Solanum tuberosum L.) is one of the world’s most important crops for human consumption, thus it is an integral part of the worlds food supply. Poland is the worlds 8th largest producer (2nd in the EU), with 9 million tons annually. Potato is susceptible to a wide range of pathogenic organisms, which can cause severe quality and yield losses worldwide. Given the absence of cultivars resistant to pathogens and the immunization of pathogen isolates to successive fungicides, any attempt to understand and strengthen the knowledge of factors related to natural potato immunity is extremely important.
In light of this, it is well documented that nitric oxide (•NO) is a key element involved in pathogen recognition as well as activation of local and systemic plant defense signaling activities and pathways. Moreover, the interdisciplinary group proposing this plan recently reported endogenous production of HNO (nitroxyl) in plant tissues (Arabidopsis thaliana) for the first time, and points toward a novel regulatory role. Under physiological conditions, HNO concentration in plant cells is in the nanomolar range. The ubiquitous HNO bioavailability allows it to support or compete with •NO signaling, depending on the local redox environment (shifts with stress or senescence). Finally, we showed that HNO formation is an early reductive stress-related response.
Taking all this into account, this proposal will focus on the real-time detection and visualization of simultaneously endogenous HNO and NO in leaves of the important crop plant challenge inoculated with vr/avr Phytophthora infestans, a cause of late blight disease. Moreover, it will be an important issue to answer the question of whether and to what degree the HNO presence in cells modifies the plants defense responses. The hypothesis is that HNO is generated during potato - P. infestans interaction and can act as a functional signal molecule favoring redox changes towards effective defense responses in potato.