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BACKGROUND: Effective utilization of plant protection UAVs in peanut cultivation management necessitates a comprehensive grasp of how application volume rates and pesticides influence peanut leaf spot and rust control. This study aimed to compare the effects of application volume rates and pesticides on droplet deposition, disease, leaf retention rate and peanut yield. A T20 plant protection unmanned aerial vehicle (UAV) sprayer was used to apply four various pesticide doses. In comparison, a knapsack sprayer was used to spray with an application volume rate of 450 L ha−1. RESULTS: The results showed a significant difference in droplet deposition between the plant protection UAVs and the electric knapsack sprayer. In the pesticide treatment with an application volume rate of 15.0 L ha−1, there was no significant difference in the deposition on the peanut canopy of each pesticide treatment, but there was a significant difference in the deposition on the ground in the treatment with adding vegetable oil adjuvant. The treatment with added vegetable oil additives showed the worst performance. The treatment with an application volume rate of 22.5 L ha−1 showed the best performance, with the leaf spot control effect being only 0.3% lower than that of the electric knapsack sprayer. CONCLUSION: Plant protection UAV spraying is feasible to control peanut diseases. Considering the operational effectiveness of the plant protection UAV and application volume rate, it is recommended to use an application volume rate of 22.5 L ha−1 without adding vegetable oil adjuvants for field operations. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

New Findings: What is the central question of this study?What is the protective benefit of n−3 polyunsaturated fatty acids (PUFAs) on liver fibrosis and what are the relevant signalling pathways in a transgenic mouse model overexpressing the mfat‐1 enzyme?What is the main finding and its importance?n−3 PUFA elevation strongly prevented carbon tetrachloride (CCl4)‐induced hepatic damage and inhibited the activation of hepatic stellate cells. n−3 PUFAs suppressed CCl4‐induced activation of mTOR, elevated Bcl‐2 expression, and reduced Bax level, suggesting that n−3 PUFAs can render strong protective effects against liver fibrosis and point to the potential of mfat‐1 gene therapy as a treatment modality. Liver fibrosis is a reversible wound healing response with excessive accumulation of extracellular matrix proteins. It is a globally prevalent disease with ultimately severe pathological consequences. However, very few current clinical therapeutic options are available. Nutritional addition of n−3 polyunsaturated fatty acids (PUFAs) can delay and lessen the development of liver fibrosis. Herein, this study examined the protective benefit of n−3 PUFAs on liver fibrosis and the relevant signalling pathways using a transgenic mouse model overexpressing the mfat‐1 enzyme that converts n−6 to n−3 PUFAs. Male C57BL/6 wild‐type and mfat‐1 transgenic mice were administered carbon tetrachloride (CCl4) or control corn oil by intraperitoneal injection. Blood alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels were subsequently measured. CCl4‐induced hepatic damage and fibrosis were assessed using haematoxylin–eosin and Masson's trichrome staining. Western blot assays were used to detect and quantify fibrosis‐related proteins and mechanistic target of rapamycin (mTOR) and B‐cell lymphoma 2 (Bcl‐2)/Bcl‐2‐associated X protein (Bax) signalling components. The direct effect of docosahexaenoic acid (DHA) on primary hepatic stellate cells (HSCs) was also investigated in a co‐culture experiment. n−3 PUFAs, as a result of mfat‐1 activity, had a strong protective effect on liver fibrosis. The elevation of ALT and AST induced by CCl4 was significantly lessened in the mfat‐1 mice. Histological determination revealed the protective effects of n−3 PUFAs on liver inflammation and collagen deposition. Co‐incubation with DHA reduced the expression of profibrogenic factors in the primary HSCs. Moreover, mfat‐1 transgenic mice showed significant reduction of proteins that are involved in mTOR and Bcl‐2/Bax signalling pathways. Collectively, these results suggest that n−3 PUFA elevation strongly prevents CCl4‐induced hepatic damage by directly inhibiting the activation of HSCs and regulating the basal activity of the mTOR and Bcl‐2/Bax signalling pathways. Gene therapy applying mfat‐1 and elevating n−3 PUFAs represents a promising treatment strategy to prevent liver fibrosis. [ABSTRACT FROM AUTHOR]

Plant protection drone spraying technology is widely used to prevent and control crop diseases and pests due to its advantages of being unaffected by crop growth patterns and terrain restrictions, high operational efficiency, and low labor requirements. The operational parameters of plant protection drones significantly impact the distribution of spray droplets, thereby affecting pesticide utilization. In this study, a field experiment was conducted to determine the working modes of two representative plant protection drones and an electric backpack sprayer as a control to explore the characteristics of droplet deposition with different spray volumes in the citrus canopy. The results showed that the spraying volume significantly affected the number of droplets and the spray coverage. The number of droplets and the spray coverage area on the leaf surface were significantly increased by increasing the spray volume from 60 L/ha to 120 L/ha in plant protection drones. Particularly for the DJI T30, the mid-lower canopy showed a spray coverage increase of 52.5%. The droplet density demonstrated the most significant variations in the lower inner canopy, ranging from 18.7 droplets/cm 2 to 41.7 droplets/cm 2 by XAG V40. From the deposition distribution on fruit trees, the plant protection drones exhibit good penetration ability, as the droplets can achieve a relatively even distribution in different canopy layers of citrus trees. The droplet distribution uniformity inside the canopy is similar for XAG V40 and DJI T30, with a variation coefficient of approximately 50%-100%. Compared to the plant protection drones, the knapsack electric sprayer is suitable for pest and disease control in the mid-lower canopy, but they face challenges of insufficient deposition capability in the upper canopy and overall poor spray uniformity. The distribution of deposition determined in this study provides data support for the selection of spraying agents for fruit trees by plant protection drones and for the control of different pests and diseases., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Yan, Lan, Wang, Hussain, Wang, Yu, Shan, Wang and Song.)