Spatial and Temporal Variability of Plant Leaf Responses Cascade after PSII Inhibition: Raman, Chlorophyll Fluorescence and Infrared Thermal Imaging

The use of photosystem II (PSII) inhibitors allows simulating cascade of defense and damage responses, including the oxidative stress. In our study, PSII inhibiting herbicide metribuzin was applied to the leaf of the model plant species Chenopodium album. The temporally and spatially resolved cascade of defense responses was studied noninvasively at the leaf level by combining three imaging approaches: Raman spectroscopy as a principal method, corroborated by chlorophyll a fluorescence (ChlF) and infrared thermal imaging. ChlF imaging show time-dependent transport in acropetal direction through veins and increase of area affected by metribuzin and demonstrated the ability to distinguish between fast processes at the level of electron transport (1 − Vj) from slow processes at the level of non-photochemical energy dissipation (NPQ) or maximum efficiency of PSII photochemistry (Fv/Fm). The high-resolution resonance Raman images show zones of local increase of carotenoid signal 72 h after the herbicide application, surrounding the damaged tissue, which points to the activation of defense mechanisms. The shift in the carotenoid band indicates structural changes in carotenoids. Finally, the increase of leaf temperature in the region surrounding the spot of herbicide application and expanding in the direction to the leaf tip proves the metribuzin effect on slow stomata closure.

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Evaluation on the Usefulness of the U-Net Segmentation Model for Auto-Diagnosis of Lumbar Disc Herniation Using Digital Infrared Thermal Imaging (DITI)

Journal of rehabilitation welfare engineering & assistive technology ◽

10.21288/resko.2018.12.4.249 ◽

2018 ◽

Vol 12 (4) ◽

pp. 249-255

Author(s):

H. I. Ju ◽

Y. M. Kim ◽

K. S. Tae

Keyword(s):

Lumbar Disc Herniation ◽

Disc Herniation ◽

Thermal Imaging ◽

Lumbar Disc ◽

Infrared Thermal Imaging

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Infrared thermal imaging denoising method based on second-order channel attention mechanism

Infrared Physics & Technology ◽

10.1016/j.infrared.2021.103789 ◽

2021 ◽

pp. 103789

Author(s):

Zhuo Li ◽

Shaojuan Luo ◽

Meiyun Chen ◽

Heng Wu ◽

Tao Wang ◽

...

Keyword(s):

Thermal Imaging ◽

Second Order ◽

Attention Mechanism ◽

Denoising Method ◽

Infrared Thermal Imaging

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Proteomics and Metabolomics Studies on the Biotic Stress Responses of Rice: an Update

Rice ◽

10.1186/s12284-021-00461-4 ◽

2021 ◽

Vol 14 (1) ◽

Author(s):

Kieu Thi Xuan Vo ◽

Md Mizanor Rahman ◽

Md Mustafizur Rahman ◽

Kieu Thi Thuy Trinh ◽

Sun Tae Kim ◽

...

Keyword(s):

Stress Responses ◽

Biotic Stress ◽

Defense Mechanisms ◽

Defense Responses ◽

Global Changes ◽

Biotic Stresses ◽

Novel Proteins ◽

Stress Agent ◽

Global Food ◽

Shed Light

AbstractBiotic stresses represent a serious threat to rice production to meet global food demand and thus pose a major challenge for scientists, who need to understand the intricate defense mechanisms. Proteomics and metabolomics studies have found global changes in proteins and metabolites during defense responses of rice exposed to biotic stressors, and also reported the production of specific secondary metabolites (SMs) in some cultivars that may vary depending on the type of biotic stress and the time at which the stress is imposed. The most common changes were seen in photosynthesis which is modified differently by rice plants to conserve energy, disrupt food supply for biotic stress agent, and initiate defense mechanisms or by biotic stressors to facilitate invasion and acquire nutrients, depending on their feeding style. Studies also provide evidence for the correlation between reactive oxygen species (ROS) and photorespiration and photosynthesis which can broaden our understanding on the balance of ROS production and scavenging in rice-pathogen interaction. Variation in the generation of phytohormones is also a key response exploited by rice and pathogens for their own benefit. Proteomics and metabolomics studies in resistant and susceptible rice cultivars upon pathogen attack have helped to identify the proteins and metabolites related to specific defense mechanisms, where choosing of an appropriate method to identify characterized or novel proteins and metabolites is essential, considering the outcomes of host-pathogen interactions. Despites the limitation in identifying the whole repertoire of responsive metabolites, some studies have shed light on functions of resistant-specific SMs. Lastly, we illustrate the potent metabolites responsible for resistance to different biotic stressors to provide valuable targets for further investigation and application.

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