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[学术文献 ] Ectropis obliqua-Induced Secondary Metabolites Are Regulated by Methyl Jasmonate in a Threshold-Dependent Manner 进入全文
International Journal of Molecular Sciences 期刊
In this study, we investigated seven key special metabolites, including p-coumaroylputrescine, feruloylputrescine, prunin, naringenin, and three monolignols, to address this knowledge gap. Epicatechin was selected as a positive control based on its well-documented regulation through the JA signaling pathway. Notably, the content of all selected compounds was significantly increased by E. obliqua infestation. Furthermore, exogenous application of high-dose methyl jasmonate (MeJA) induced the accumulation of six of the eight compounds, excluding p-coumaryl alcohol and sinapyl alcohol, whereas low-dose MeJA failed to elicit their accumulation. To confirm the results, we screened two bioactive molecules, D-allose and L-theanine, which significantly increased the endogenous JA levels at low concentrations. Interestingly, neither D-allose nor L-theanine triggered the biosynthesis of these defensive compounds. Additionally, D-allose-treated tea leaves had no significant effect on the performance of E. obliqua larvae. These findings demonstrate that the metabolic accumulation induced by E. obliqua is mediated through a high-threshold JA signaling cascade. This study provides novel insights into the relationship between plant resistance and JA signaling pathway, advancing our understanding of special metabolites mediated plant-insect interactions.
[相关专利 ] A colorimetric sensor array for volatile organic compounds analysis 进入全文
新加坡专利
本发明公开了一种用于检测挥发性有机化合物（VOCs）的比色传感器阵列，以及包括所述比色传感器阵列的系统。还公开了使用所述比色传感器阵列和/或系统的方法。利用该方法能够将样品中的气味可视化成比色指纹，可以对样品中VOCs进行快速、精确、简便和低成本的定性识别和半定量分析。
[会议论文 ] Integrating LSPR and SERS for Rapid and Effective Visualization and Identification of Volatile Organic Compounds Distribution 进入全文
IEEE 会议
Microbial volatile organic compounds (MVOCs) can serve as a diagnostic tool for assessing the respiratory status of microorganisms. Localized surface plasmon resonance (LSPR) sensors are noted for their rapid response and straightforward operation; however, they often struggle to provide specific information about the detected substances and to differentiate between gas types. In contrast, gas sensors utilizing surface-enhanced Raman spectroscopy (SERS) technology offer excellent selectivity and can generate unique “fingerprint” signals, enabling easy identification and distinction of various gas molecules. Integrating these two technologies promises to enhance the visualization of volatile organic compound distributions both more effectively and expeditiously.
[学术文献 ] Classification and identification of tea diseases based on improved YOLOv7 model of MobileNeXt 进入全文
Scientific Reports 期刊
To address the issues of low accuracy and slow response speed in tea disease classification and identification, an improved YOLOv7 lightweight model was proposed in this study. The lightweight MobileNeXt was used as the backbone network to reduce computational load and enhance efficiency. Additionally, a dual-layer routing attention mechanism was introduced to enhance the model’s ability to capture crucial details and textures in disease images, thereby improving accuracy. The SIoU loss function was employed to mitigate missed and erroneous judgments, resulting in improved recognition amidst complex image backgrounds.The revised model achieved precision, recall, and average precision of 93.5%, 89.9%, and 92.1%, respectively, representing increases of 4.5%, 1.9%, and 2.6% over the original model. Furthermore, the model’s volum was reduced by 24.69M, the total param was reduced by 12.88M, while detection speed was increased by 24.41 frames per second. This enhanced model efficiently and accurately identifies tea disease types, offering the benefits of lower parameter count and faster detection, thereby establishing a robust foundation for tea disease monitoring and prevention efforts.
[学术文献 ] A Preliminary Study for Ultraviolet Optical Methyl Salicylate Monitoring in Agriculture 进入全文
Sensors-Basel 期刊
Methyl Salicylate, commonly known as wintergreen oil, is a volatile organic compound which plays a crucial role in agriculture as a signaling compound for plant defense mechanisms and as an attractant for beneficial insects. Rapid and accurate detection of Methyl Salicylate is pivotal for understanding plant responses to stress and plant-to-plant communication, and it is crucial for pest management. In this work, we propose a proof of concept for Methyl Salicylate detection in agriculture, exploiting a solid-state sensor technology. Our attention is focused on the monitoring of the second characteristic Methyl Salicylate optical absorption peak, at about 310 nm. To achieve this, we developed an optical sensing apparatus comprising a UV source, a silicon carbide visible-blind UV detector, and a chamber with a 16 cm optical path. This configuration enables testing of various Methyl Salicylate concentrations and achieves a detection limit as low as 70 ppb at room temperature. Preliminary cross-testing with Methyl Jasmonate demonstrated selectivity for Methyl Salicylate, confirming the sensor’s specificity. Additionally, a design for a compact and handheld system for on-site volatile organic compound monitoring in the agricultural field is also proposed.
[学术文献 ] Rapid detection of volatile organic compounds emitted from plants by multicapillary column-ion mobility spectrometry 进入全文
Analytical Methods 期刊
This study presents a novel rapid analytical method for the detection of volatile organic compounds (VOCs) emitted from blueberry leaves using the Tenax adsorbent followed by separation using a multicapillary column (MCC) and Ion Mobility Spectrometry (IMS) detection. The emitted VOCs including caryophyllene, benzene acetonitrile, linalool, ocimene, and methyl salicylate initiated by different stress factors including mechanical damage (punching), herbivore attack (aphids) and methyl jasmonate (MeJA) spraying were detected and quantified. Limits of Detection (LODs) for the VOCs were determined in the range of 8 to 33 ng. This new cost-efficient method provided a simple and direct detection of the emitted VOCs from plants without any sample pretreatment.
