Journal of Energy Bioscience 2025, Vol.16, No.2, 64-74 http://bioscipublisher.com/index.php/jeb 67 3.1.3 Effects of extreme temperatures on ROS production in potato tissues The level of ROS in potatoes increases when exposed to high or low temperatures. High temperatures accelerate the metabolic activity of cells, causing a rapid increase in ROS. Low temperatures may cause problems in the photosynthesis system and also lead to ROS accumulation (Hasanuzzaman et al., 2020; Panda et al., 2024). ROS triggered by these temperatures can cause oxidative stress, damage cells, and affect the normal development of plants (Jajić et al., 2015; Czarnocka and Karpiński, 2018). Potatoes will activate some protective mechanisms to cope with it, such as producing heat shock proteins or low temperature response genes, which can help stabilize proteins and cell membrane structures. At the same time, the antioxidant system will also increase its efforts to remove excess ROS (Das and Roychoudhury, 2014; You and Chan, 2015). Whether or not ROS levels can be regulated in time and these protective responses can be initiated is the key to potato's ability to withstand extreme temperatures (Alscher et al., 1997; Mahalingam and Fedoroff, 2003). 3.2 Biotic stress 3.2.1 ROS bursts during pathogen attacks on potatoes When pathogens invade, potatoes will produce a large amount of ROS in a short period of time. This phenomenon is called "oxygen burst". Oxygen burst is a reaction used by plants to prevent the spread of pathogens and is part of the early defense response. ROS will cause some cells to die, thereby controlling the pathogens in a local area (Mahalingam and Fedoroff, 2003; Czarnocka and Karpiński, 2018). These ROS will also serve as signals to activate the expression of defense genes and improve the immunity of the entire plant (Alscher et al., 1997; Das and Roychoudhury, 2014). However, this process must be strictly controlled, otherwise it is easy to damage the plant's own tissues. In this process, the antioxidant system of potatoes will intervene to adjust the level of ROS to ensure that they only work when needed and do not cause excessive damage (Jajić et al., 2015; Hasanuzzaman et al., 2020). This balance is very important for disease resistance (Czarnocka and Karpiński, 2018 ; Panda et al., 2024 ). 3.2.2 Role of ROS in potato herbivore defense mechanisms When insects eat potatoes, potatoes also use ROS as a defense. On the one hand, these ROS can directly damage the cell tissues in the insect body, playing a deterrent role; on the other hand, ROS can also act as a signal, allowing the plant to produce some toxic or insect-unpleasant compounds, thereby playing a repellent role (Alscher et al., 1997; Mahalingam and Fedoroff, 2003). This ROS-induced reaction is an important part of potato's defense against insects (Das and Roychoudhury, 2014; Czarnocka and Karpiński, 2018). In this process, ROS usually also activates signaling pathways, prompting the plant to synthesize defense compounds such as phenols and alkaloids, increasing potato's resistance to insects and strengthening the overall defense effect (Jajić et al., 2015; Panda et al., 2024). The coordination between ROS and these defense substances is the key to the success of the defense system (Czarnocka and Karpiński, 2018 ; Hasanuzzaman et al., 2020 ). 3.2.3 General oxidative stress responses in potatoes to biotic factors Whether it is pathogens or insects, potatoes usually respond by producing ROS when encountering biotic stress. These ROS can not only directly participate in defense, but also send out signals to activate more defense mechanisms (Alscher et al., 1997; Mahalingam and Fedoroff, 2003). The potato response process is a complex system, including the generation of ROS, signal transduction, and the process of clearing ROS. The antioxidant system will also be strengthened here to maintain ROS within a reasonable range (Jajić et al., 2015; Hasanuzzaman et al., 2020). In this way, ROS can play a role without causing too much damage to the plant itself. This flexible regulatory ability is the key to potato's "resistance" in the face of biological stress (Czarnocka and Karpiński, 2018; Panda et al., 2024). 4 ROS as Signaling Molecules in Potato Stress Responses 4.1 ROS-triggered activation of stress-responsive genes in potatoes Reactive oxygen species (ROS) play a critical "signaling" role when potatoes respond to stress. Once a plant is stressed, ROS are often one of the first molecules produced. They act like switches to turn on the expression of
RkJQdWJsaXNoZXIy MjQ4ODYzNA==