Magnaporthe oryzae causes a fungal disease that poses a serious risk to global food security. Nanoagrochemicals are perceived as sustainable, economical, and environmentally friendly alternatives to traditional pesticides. Plant immune activators can be applied as the active ingredients of nanopesticides to control diseases in agriculture, but their use is limited and corresponding research is lacking. In this study, a nanodelivery system (PBZ@CaCO3@SG) for the on-demand release of a plant immune activator (probenazole; PBZ) was prepared using nano-CaCO3 after coating with sodium alginate-gelatin (SG). In vitro, at 48 h, the release rate reached 97.9% and 88.4% at pH 4.5 and 6.0, respectively, which greatly exceeded that under neutral conditions (pH 7.4), with acid-responsive release characteristics. Moreover, it responded quickly to the acidic microenvironment generated during M. oryzae infestation and rationally released PBZ, effectively improving plant resistance to M. oryzae and minimizing disease. Notably, M. oryzae infection was markedly reduced, by 60.6%, after PBZ@CaCO3@SG treatment. Mechanistically, PBZ@CaCO3@SG enhanced both physical barrier formation and systemic acquired resistance in rice, enhancing resistance to M. oryzae. It also showed good biosafety for both microbial communities and earthworms in the soil. This comprehensive study revealed multiple mechanisms by which PBZ@CaCO3@SG interacts with plants and pathogens, inhibits damage, and maintains nontarget biosafety, emphasizing its great potential for plant disease management.

Nanotechnology, which involves manipulating matter at the atomic and molecular scales to produce structures and devices ranging from 1 to 100 nm, is increasingly being applied in agriculture. Nanoscale materials possess distinct optical, electrochemical, and mechanical properties that enable the smart, targeted delivery of pesticides, fertilizers, and genetic materials to plants, as well as rapid sensing and on-site monitoring of plant health, soil fertility, and water quality in a digital format. This review explores the application of nanotechnology in agriculture, examining the challenges and benefits related to all aspects of crop production, with a particular focus on regulatory issues. Key findings indicate that nanotechnology can improve crop production and reduce the environmental footprint of agriculture through precise input management. However, several critical issues need to be addressed, including the limited knowledge of the long-term environmental impacts associated with agricultural nanotechnology and the ambiguity of current regulations. This underscores the need for further research to elucidate its impact on soil, water, and environmental and human health, to inform evidence-based regulations. (c) 2024 The Author(s). Journal of the Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Sclerotinia sclerotiorum is one of the fungi that cause plant diseases. It damages plants by secreting large amounts of oxalic acid and cell wall-degrading enzymes. To meet this challenge, we designed a new pH/enzyme dual-responsive nanopesticide Pro@ZnO@Pectin (PZP). This nanopesticide uses zinc oxide (ZnO) as a carrier of prochloraz (Pro) and is encapsulated with pectin. When encountering oxalic acid released by Sclerotinia sclerotiorum, the acidic environment promotes the decomposition of ZnO; at the same time, the pectinase produced by Sclerotinia sclerotiorum can also decompose the outer pectin layer of PZP, thereby promoting the effective release of the active ingredient. Experimental data showed that PZP was able to achieve an efficient release rate of 57.25% and 68.46% when pectinase was added or under acidic conditions, respectively. In addition, in vitro tests showed that the antifungal effect of PZP was comparable to that of the commercial Pro (Pro SC) on the market, and its efficacy was 1.40 times and 1.32 times that of the Pro original drug (Pro TC), respectively. Crucially, the application of PZP significantly alleviated the detrimental impacts of Pro on wheat development. Soil wetting experiments have proved that PZP primarily remained in the soil, thereby decreasing its likelihood of contaminating water sources and reducing potential risks to non-target organisms. Moreover, PZP improved the foliar wettability of Pro, lowering the contact angle to 75.06 degrees. Residue analyses indicated that PZP did not elevate prochloraz residue levels in tomato fruits compared to conventional applications, indicating that the nanopesticide formulation does not lead to excessive pesticide buildup. In summary, the nanopesticide PZP shows great promise for effectively managing Sclerotinia sclerotiorum while minimizing environmental impact.

During the development of green agriculture and pesticide use, reducing pesticides use and improving control efficiency is imperative. To date, new pesticide formulations created by nanotechnology can be expected to overcome the difficulties that cannot be solved by the traditional pesticide processes and make pesticide formulations close to the needs of green agricultural production. As natural polysaccharides, Xanthan gum (XG) charactered by a repeated units and side chain of D-glucose, d-mannose, and d-glucuronic acid, and thereby having the unprecedented features in response to wide practice in various fields. This review introduces the properties of the natural polymer XG and its current status of application in agriculture, focusing on the pesticide adjuvant and preparation of novel pesticide and fertilizer delivery systems (such as core-shell and hydrogel), and combined with the applications in mulch film and soil engineering. Furthermore, the properties of Xanthooligosaccharides suitable for agriculture were discussed. Finally, the potential of XG for the creation of nanopesticides and its future prospects are highlighted. Taken together, XG's excellent performance endows it with a wide range of applications in the agriculture field, and result in strong stimulating the sustainable development of agriculture and evolution of agricultural industry.

The development of intelligently released and environmentally safe nanocarriers not only aligns with the sustainable agricultural strategy but also offers a potential solution for controlling severe soil-borne bacterial diseases. Herein, the core-shell structured nanocarrier loaded with honokiol bactericide (honokiol@ZnO-ZIF-8) was synthesized via a one-pot method for the targeted control of Ralstonia solanacearum, the causative agent of tobacco bacterial wilt disease. Results indicated that honokiol@ZnO-ZIF-8 nanoparticles induced bacterial cell membrane and DNA damage through the production of excessive reactive oxygen species (ROS), thereby reducing bacterial cell viability and ultimately leading to bacterial death. Additionally, the dissociation mechanism of the nanocarriers was elucidated for the first time through thermodynamic computational simulation. The nanocarriers dissociate primarily due to H+ attacking the N atom on imidazole, causing the rupture of the Zn-N bond under acidic conditions and at room temperature. Furthermore, honokiol@ZnO-ZIF-8 exhibited potent inhibitory effects against other prominent Solanaceae pathogenic bacteria (Pseudomonas syringae pv. tabaci), demonstrating its broad-spectrum antibacterial activity. Biosafety assessment results indicated that honokiol@ZnO-ZIF-8 exhibited non-phytotoxicity towards tobacco and tomato plants, with its predominant accumulation in the roots and no translocation to aboveground tissues within a short period. This study provides potential application value for the intelligent release of green pesticides. Environment implication: The indiscriminate use of agrochemicals poses a significant threat to environmental, ecological security, and sustainable development. Slow-release pesticides offer a green and durable strategy for crop disease control. In this study, we developed a non-phytotoxic and pH-responsive honokiol@ZnO-ZIF-8 nano-bactericide based on the pathogenesis of Ralstonia solanacearum. Thermodynamic simulation revealed the dissociation mechanism of ZIF-8, with different acidity controlling the dissociation rate. This provides a theoretical basis for on-demand pesticide release while reducing residue in the. Our findings provide strong evidence for effective soil-borne bacterial disease control and on-demand pesticide release.