Hangyu Guo,Yaqin Zhang,Fange Kong,Chunxia Wang,Shanshan Chen,Jiasi Wang,Di Wang
Alternaria solani ( A. solani ), the causal agent of early blight in potatoes, poses a serious and persistent threat to potato production worldwide. Therefore, developing a method that can accurately detect A. solani in the early stage to avoid further spread is urgent. However, the conventional PCR-based method is not appropriate for application in the fields. Recently, the CRISPR-Cas system has been developed for nucleic acids analysis at point-of-care. Here, we propose a gold nanoparticles-based visual assay combining loop-mediated isothermal amplification with CRISPR-Cas12a to detect A. solani . After optimization, the method could detect 10 −3 ng/μL genomic gene of A. solani . The specificity of the method was confirmed by discriminating A. solani from other three highly homologous pathogens. We also developed a portable device that could be used in the fields. By integrating with the smartphone readout, this platform holds significant potential in high-throughput detection of multiple pathogens in the fields.
Ling Zhang,Yu Long,Long-Fei Li,Xiang-Wei Xin,Xiao-Di Chen,Xiang Zhou,Li-Wei Liu,Zhi-Bing Wu,Song Yang
The overreliance on traditional chemical fungicides, combined with the emergence of resistance, poses significant challenges for food safety. Early blight, caused by the fungal pathogen Alternaria solani ( A. solani ), is among the most significant contributors to pre- and postharvest yield losses in tomato cultivation. To address this challenge, through evaluation of the antifungal activity of 52 commercially available natural products against A. solani , we revealed for the first time that the naturally occurring compound genistein exhibited potent fungicidal activity against A. solani , with an EC 50 value of 6.53 μg/mL, surpassing that of chlorothalonil (EC 50 = 8.35 μg/mL). In vivo assays demonstrated that genistein exhibited strong protective (48.1 %) and therapeutic (42.5 %) efficacy, effectively safeguarding tomatoes from fungal infection. Mechanistic investigations, including transcriptomic analysis, scanning electron microscopy, fluorescence imaging, and measurements of malondialdehyde and ATP levels, collectively indicated that genistein disrupted energy metabolism, leading to reactive oxygen species (ROS) accumulation. This oxidative stress cascade triggered both apoptotic-like responses and membrane lipid peroxidation, ultimately inhibiting the growth of A. solani . Interestingly, genistein showed enhanced anti- A. solani activity when used in combination with either chlorothalonil or tebuconazole. Additionally, genistein displayed low phytotoxicity and favorable drug-likeness properties. Taken together, these findings elucidate the mechanisms underlying genistein's antifungal activity against A. solani , underscoring its promise as a natural antifungal agent for enhancing food safety and improving tomato yield and quality. Furthermore, this study provides valuable insights for the rational design of flavonoid-based antifungal agents.
危险品化学品经营许可证（带存储）