Adhesive Nanocomposite for Prolonging Foliar Retention and Synergistic Weeding and Nourishing

Abstract

efficiency of fertilizer and pesticide is growing to solve these problems. [8][9][10] Controlled release pesticide-fertilizer combination (CRPFC), playing a synergistic effect of pesticide and fertilizer, is an effective approach to achieve sustainable circulative agriculture and has garnered considerable attention all over the world. [11,12] Compared with traditional controlledrelease pesticide or fertilizer, CRPFC unifies the two most important agrochemicals used in agriculture, and combine the plant protection of pesticide and the nutrients supply of fertilizer into one field operation. It cannot only save labor but also reduce time and energy consumption. Various materials have been developed recently to be used as carriers of pesticide and fertilizer, such as organic polymers, [13] bio-sourced matrices, [14] and inorganic materials. [15,16] However, most of them only provide individual function and are accompanied by complex preparation processes. Furthermore, they are very susceptible to being washed away by rain, which limit their real applications. [17] Therefore, develop an adhesive carrier for extensive use of CRPFC in agriculture is still a challenge.Nanotechnology represents a new direction for the carrier development. [18][19][20][21] Over the past years, the applications and benefits of nanotechnology, especially nanoparticles as pesticide or fertilizer carrier platforms, have generated immense developments. [22][23][24] Recently, mesoporous silica nanoparticles (MSNs) show superior performance as support for fertilizer or pesticide controlled release due to their easy functionalization modification, controllable morphology, adjustable pore volume, and thermal stability. [25][26][27][28][29] However, the adsorption capacity of MSNs was a great limitation because there are no functional sites on MSNs surface. [30] It was reported that by grafting highdensity carboxyl groups onto the pore surface of MSNs and complexing with platinum atoms, the drug loading efficiency of MSNs can be greatly improved. [31] In this work, MSNs functionalized by positive charges were developed to achieve a high loading capacity of pesticide and fertilizer (Scheme 1). Then the nanoparticles were coated by polydopamine (PDA) via self-polymerization. [32][33][34] As a kind of catecholamines, PDA is expected to be active for metals ions, [35] The volatilization and leaching for most fertilizers and pesticides raise questions about the sustainability of ecosystems. To enhance the utilization of fertilizers and pesticides, pesticide-fertilizer combined nanocomposites are developed to prolong foliar retention and play a synergistic effect of weeding and nourishing for plant growth. The pesticide-fertilizer combined nano composites are prepared based on positive-charge functionalized mesoporous silica and polydopamine, by chelating micronutrients (Zn 2+ ) and loading pesticide 2,4-D. A high loading capacity of Zn 2+ (233.4 mg g −1 ) and 2,4-D (17.8%) is achieved. Zn 2+ and the pesticide show excellent pH-responsive release behavio...

Toward Sustainable Crop Protection: Aqueous Dispersions of Biodegradable Particles with Tunable Release and Rainfastness

“…The development of intensive agriculture techniques and agrochemicals, especially pesticides, in the mid-20 th century are responsible for feeding the bulk of global population today. [1][2][3] About 4.1 million tons of pesticides were applied globally in 2018, which contributed to protecting almost 30% output of assembly, wherein a high surface area to volume ratio is desirable for enhanced adhesion/encapsulation of AIs for controlled release applications. [18] To prepare nanoscale particles of CEs, various bottom-up techniques such as emulsification-evaporation, solvent displacement, and dialysis have been developed; [19][20][21] however the use of high boiling point organic and chlorinated solvents, [18,19] additional polymers as stabilizing agents taken together with the risk of polymer degradation during the sonication process [19] are significant impediments to the use of these approaches for drug/AI encapsulation applications.…”

“…The development of intensive agriculture techniques and agrochemicals, especially pesticides, in the mid‐20 th century are responsible for feeding the bulk of global population today. [ 1–3 ] About 4.1 million tons of pesticides were applied globally in 2018, which contributed to protecting almost 30% output of global agricultural products. [ 1,4–6 ] The importance of pesticides notwithstanding, negative impacts on terrestrial and aquatic biodiversity, deleterious effects on non‐target organisms, increased pathogen resistance, and accumulation in the food chain are some of the negative effects because of the overuse of pesticides.…”

“…Controlled release formulations bond or encapsulate the AI within a micro/nanoscale carrier typically developed from a polymer. [ 2,3,8,9 ]…”

“…Controlled release formulations bond or encapsulate the AI within a micro/nanoscale carrier typically developed from a polymer. [2,3,8,9] Traditional pesticide delivery methods involve larger application volumes of AI, with approximately 90% wasted on nontargets, or through environmental loss and degradation. [1,5] In contrast, controlled release formulations can help tailor the bioavailability of a small quantity of AI based on crop and soil environment requirements while minimizing operation hazards and reducing the inhalation and contact toxicity of the pesticides to the non-targets.…”

An Alkali-Triggered Polydopamine Modified Mesoporous Silica Nanopesticide for Smart Delivery of Chlorpyrifos with Low Loss

“…Figure f shows a schematic diagram of the forces of the Cpf-MSNs@PDA droplet on the hydrophobic leaves; the three key forces for the droplet to maintain balance were gravity, support, and adhesion. Due to the abundant catechol groups in PDA, the adhesion of the PDA wrapped nanopesticide to the leaves was impressively enhanced by the interaction with hydroxyl groups of the crop leaves’ cuticle through hydrogen bonds, which effectively prevented the rolling loss of Cpf-MSNs@PDA. , …”