The rise in the World’s food demand in line with the increase of the global population has resulted in calls for more research on the production of sustainable food and sustainable agriculture. A natural biopolymer, chitosan, coupled with nanotechnology could offer a sustainable alternative to the use of conventional agrochemicals towards a safer agriculture industry. Here, we review the potential of chitosan-based agronanochemicals as a sustainable alternative in crop protection against pests, diseases as well as plant growth promoters. Such effort offers better alternatives: (1) the existing agricultural active ingredients can be encapsulated into chitosan nanocarriers for the formation of potent biocides against plant pathogens and pests; (2) the controlled release properties and high bioavailability of the nanoformulations help in minimizing the wastage and leaching of the agrochemicals’ active ingredients; (3) the small size, in the nanometer regime, enhances the penetration on the plant cell wall and cuticle, which in turn increases the argochemical uptake; (4) the encapsulation of agrochemicals in chitosan nanocarriers shields the toxic effect of the free agrochemicals on the plant, cells and DNA, thus, minimizing the negative impacts of agrochemical active ingredients on human health and environmental wellness. In addition, this article also briefly reviews the mechanism of action of chitosan against pathogens and the elicitations of plant immunity and defense response activities of chitosan-treated plants.

Fungicide is used to control fungal disease by destroying and inhibiting the fungus or fungal spores that cause the disease. However, failure to deliver fungicide to the disease region leads to ineffectiveness in the disease control. Hence, in the present study, nanotechnology has enabled the fungicide active agents (hexaconazole) to be encapsulated into chitosan nanoparticles with the aim of developing a fungicide nanodelivery system that can transport them more effectively to the target cells (Ganoderma fungus). A pathogenic fungus, Ganoderma boninense (G. boninense), is destructive to oil palm whereby it can cause significant loss to oil palm plantations located in the Southeast Asian countries, especially Malaysia and Indonesia. In regard to this matter, a series of chitosan nanoparticles loaded with the fungicide, hexaconazole, was prepared using various concentrations of crosslinking agent sodium tripolyphosphate (TPP). The resulting particle size revealed that the increase of the TPP concentration produced smaller particles. In addition, the in vitro fungicide released at pH 5.5 demonstrated that the fungicide from the nanoparticles was released in a sustainable manner with a prolonged release time up to 86 h. On another note, the in vitro antifungal studies established that smaller particle size leads to lower half maximum effective concentration (EC₅₀) value, which indicates higher antifungal activity against G. boninense.

The increase in the world’s oil demand due to the rise of the global population urges more research into the production of sustainable vegetable oilseeds, among which palm oil is the most suitable candidate as it is the most efficient oilseed crop in the world. In an effort to drive the oil palm industry in the areas of food safety and security nanotechnology could offer a sustainable alternative. However, the utilization of nanotechnology in the oil palm industry is still limited. In this review, we aim to encourage the researchers to fully utilize nanotechnology as an alternative solution to tackle the challenges faced by the oil palm industry. Moreover, we also aim to highlight the opportunities for nanotechnology development in oil palm-based related research. The major points are as follows: (1) Nanosensing enables real-time monitoring of plantation status and crop progression, including soil, water and nutrient management, early pest/disease detection, and the spreading of pests/diseases. The use of nanosensing conveniently extends into advanced breeding topics, such as the development of disease-tolerant plants; (2) Nanotechnology could be the answer for the development of integrated management of pest and disease. Active agricultural ingredients can be entrapped or encapsulated into nanocarrier systems to improve their solubility, stability, enhance their efficient delivery to site-specific targets, with longer shelf life, and consequently improved efficacy; (3) Valuable nanomaterials can be isolated and generated from oil palm biomass waste. The utilization of oil palm biomass waste could overcome the issue of the massive production of waste in the oil palm industry and palm oil mills, where oil only accounts for 10% of the biomass, while 90% is comprised of the generated biowastes. (4) Palm oil can be utilized as a green alternative as a capping and stabilizing agent in the biosynthesis of metallic and non-metallic nanoparticles. In addition, nanoemulsion formulations using palm oil in drug delivery systems offer advantages such as low toxicity, enhance bioavailability and solubility of the drugs, apart from being inexpensive and environmentally friendly.

Global food demand has increased in tandem with the world’s growing population, prompting calls for a new sustainable agricultural method. The scarcity of fertile soil and the world’s agricultural land have also become major concerns. Soilless and microgreen farming combined with nanotechnology may provide a revolutionary solution as well as a more sustainable and productive alternative to conventional farming. In this review, we look at the potential of nanotechnology in soilless and microgreen farming. The available but limited nanotechnology approaches in soilless farming include: (1) Nutrients nanoparticles to minimize nutrient losses and improve nutrient uptake and bioavailability in crops; (2) nano-sensing to provide real-time detection of p H, temperature, as well as quantifying the amount of the nutrient, allowing desired conditions control; and (3) incorporation of nanoparticles to improve the quality of substrate culture as crop cultivation growing medium. Meanwhile, potential nanotechnology applications in soilless and microgreen farming include: (1) Plant trait improvement against environmental disease and stress through nanomaterial application; (2) plant nanobionics to alter or improve the function of the plant tissue or organelle; and (3) extending the shelf life of microgreens by impregnating nanoparticles on the packaging or other preservation method.

The excessive use of fungicides may be of environmental and health concerns. Hence, to overcome this problem, chitosan as a controlled release matrix was used in this work to encapsulate the fungicide for the development of enhanced fungicide nanodelivery system. In this proposed study, dual-loaded fungicides (hexaconazole and dazomet) were simultaneously encapsulated into chitosan nanoparticles as an antifungal agent on Ganoderma boninense (G. boninense). In this work, we report the synthesis and characterization of the nanoparticles prepared using various concentrations of the crosslinking agent of sodium tripolyphosphate (TPP); 2.5, 5, 10, and 20 mg mL⁻¹, which resulted in the nanoparticles of CHDEN2.5, CHDEN5, CHDEN10, and CHDEN20, respectively. The effect of TPP on the synthesized nanoparticle size revealed that an increase of TPP resulted in smaller particles, which in turn play a crucial role in controlling G. boninense growth. CHDEN20 shows the highest antifungal efficacy with the lowest half-maximal effective concentration (EC₅₀) on G. boninense. The formulated nanocarrier system of fungicide aims to enhance the efficient delivery of the active ingredients to the target site, able to sustain in it for a longer time, and consequently improve the fungicide efficacy in combating the basal stem rot disease in oil palm.