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This study was conducted on Xanthomonas axonopodis pv, which causes significant economic losses in the agricultural sector. Here, we study a common bacterial blight disease caused by the phaseoli (XaP) bacterial pathogen on Üstün42 and Akbulut bean genera. In this study, a total of 4000 images, healthy and diseased, were used for both bean breeds. These images were classified by AlexNet, VGG16, and VGG19 models. Later, reclassification was performed by applying pre-processing to the raw images. According to the results obtained, the accuracy rates of the pre-processed images classified by the VGG19, VGG16 and AlexNet models were determined as 0.9213, 0.9125 and 0.8950, respectively. The models were then hybridized with LSTM and BiLSTM for raw and pre-processed images and new models were created. When the performance of these hybrid models was evaluated, it was found that the models hybridized with LSTM were more successful than the simple models, while the models hybridized with BiLSTM gave better results than the models hybridized with LSTM. In particular, the VGG19+BiLSTM model attracted attention by achieving 94.25% classification accuracy with pre-processed images. This study emphasizes the effectiveness of image processing techniques in agriculture in the field of disease detection and is important as a new dataset in the literature for evaluating the performance of hybridized models. [ABSTRACT FROM AUTHOR]

Plant pathogens have developed various independent and well-elaborated mechanisms of penetrating and accessing plant cell contents. The production of reactive oxygen species (ROS) by the consumption of molecular oxygen during host- pathogen interactions is termed the oxidative burst. The most important ROS are singlet oxygen, the hydroxyperoxyl radical, the superoxide anion, hydrogen peroxide, the hydroxyl radical and the closely related reactive nitrogen species, nitric oxide. There are profound differences between monocots and dicots as well as in the biology of biotrophic, hemibiotrophic and necrotrophic pathogens. ROS acts synergistically in a signal amplification to drive the hypersensitive reaction (HR) and the establishment of systemic defenses. The role of ROS in successful pathogenesis, it is important to try to inhibit the cell death machinery selectively and simultaneously to monitor other defense and pathogenesis-related events. With the understanding of the molecular mechanisms underlying the localized activation of the oxidative burst following perception of pathogen avirulence signals and key downstream responses including gene activation, cell death, and longdistance signaling, novel strategies will be developed for engineering enhanced protection against pathogens by manipulation of the oxidative burst and oxidantmediated signal pathways. In this review, it is assessed the different roles of ROS in host-pathogen interactions with special emphasis on plant pathogens. [ABSTRACT FROM AUTHOR]

Bacterial canker of tomato caused by Clavibacter michiganensis subsp. michiganensis produces considerable economic losses in many countries because effective control measures are lacking. In this study, the effectiveness of some chemicals, a plant growth regulator (Prohexadione-Ca (PC)), two plant activators (hydrogen peroxide (HP)) and harpin protein (Hrp), fungicides, maneb+copper (MC), copper compounds (copper sulfate pentahydrate (CSP) copper hydroxide (CH) and copper oxychloride (CO)) and an antibiotic, streptomycin sulphate on the pathogen were assessed in vitro and in vivo on two tomato cultivars, Newton and Orient. In Hrp and HP treated plants, reduction in disease severity (about 45%) was correlated with suppression of bacterial growth during the time course of infection. The activities of POX, GPX and PAL enzymes were determined at 5th day as markers of resistance and applications of Hrp, PC and HP induced a progressive and significant increase of both enzymes in locally treated tissues. Only PC treatments have decreased plant heights and the effectiveness of PC in reduction of plant heigths was up to 40%. Among copper compounds, CSP and CO combination with Maneb were the most effective on the disease severity (about 50%). In addition, CSP combination with Hrp, HP and PC significantly limited the pathogen population in vitro and they showed considerable effects on the disease symptoms compared with CSP alone. We conclude that Hrp, HP and PC may be useful in controlling external symptoms of this disease in greenhouses, and is environmentally friendly, reducing the amount of copper applied to crops. [ABSTRACT FROM AUTHOR]