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Application Nanobiopesticides Derived From Plants

Charles Oluwaseun Adetunji1* and Abel Inobeme2

1Applied Microbiology, Biotechnology and Nanotechnology Laboratory, Department of Microbiology, Edo University Iyamho, Auchi, Edo State, Nigeria

2Department of Chemistry, Edo University Iyamho, Okpella, Edo, Nigeria

Abstract

The utilization of biopesticides for the management of agricultural pest and diseases has been carried for a long time, the incorporation of the vast knowledge gained from nanotechnology only commenced recently. The integration of nanomaterials in the development of biopesticides will, therefore, help in the mitigation of some of the challenges associated with the use of biopesticides alone, such as enhancing the overall efficiency, improved stability, effective delivery while limiting some of the negative effects. Nanotechnology has, therefore, provided the adoption of responsive, biodegradable, biocompatible, and intelligent materials for the fabrication of safe, green, and efficient pesticides. It has been indicated that the integration of nanotechnology to the existing biopesticides has the potential of ensuring the design and formulation of more reliable nanobiopesticides.

Keywords: Nanobiopesticides, nanotechnology, biodegradable, biocompatible, biopesticides

1.1 Introduction

The role of nanotechnology in various areas of human endeavors, such as agriculture, medicine, industries, biotechnology among others cannot be overemphasized. The global population is rapidly increasing and the quest for quality food is increasing continually. The place of agriculture for the feeding of this population and environmental sustainability therefore becomes paramount. On yearly basis, it is reported that 25% of agricultural crops on global scale are destroyed by pests and diseases [1]. On this premise, the control and management of pest and diseases is necessary for improving agricultural yield and ensuring food safety and security. More recently, various approaches and pesticides formulations have been employed for the management of pesticides with a view to ensuring food security. Some of these include synthetic, chemical and biological measures. Basically, pesticides are grouped into different classes on the basis of their structures, compositions and targeted organisms into rodenticides, herbicides, bactericides, insecticides, fungicides, among others. The use of chemical pesticides has also been reported to posses it inherent limitation. These substances posses high toxicity to both pests and humans [2]. On global scale it has been documented that over 200,000 persons die on annual basis as a result of poisoning emerging from the use of chemical and synthetic agents. Some of the existing chemicals that have been employed in this regards have also showed some limitations as a result of challenges with efficient delivery mechanism, poor stability within the environment, low specificity, less biodegradability, as well as the high cost of formulation. The chemicals also contaminate the environment since they all pass through it polluting soils, water bodies and the atmosphere [3]. The workers in industries where these pesticides are produced are also prone to occupational hazards due to exposure to these toxic substances. Exposure to these pesticides occurs through the intake of food and water. In order to overcome the aforementioned limitations nanotechnology has shown to have promising results and prospects [4]. At present, nanotechnology has found relevance in various sectors and fields of humans in problem solving. The incorporation of nanopesticide to the area of agriculture has the potential of increasing the production of crop and improvement the mortality of pest. The use of nanobiopesticides gained remarkable attention in their usage against pests as a result of their minute sizes (1-100 nm), enhanced stability, large surface area, ease of application and cost effectiveness [5-7].

This book presents the synthesis and applications of nanobiopesticides in management of various agricultural pests and diseases causing microorganisms. Some of the areas of application covered in this word include their utilization as antirodents, antinematodes, antimites, antimollusca, antiviral agents, biocides, fumigants, ovicides, slimicides, disinfectants as well as their applications in the mitigation of various stresses associated with abiotic factors and the rejuvenation of various environment heavily polluted by numerous emerging contaminants.

1.2 Concept of Biopesticides

Biopesticides are pesticides of biological origin that are obtained majorly from natural substances or microorganisms. They are basically classified into three major groups which are the botanical biopesticides, the microbial based biopesticides and plants derived biopesticides. Biopesticides have gotten remarkable attention as alternative to the conventional agropesticides as a result of their unique features such as specificity in targeting, relatively fewer negative effects, ease of breaking down quickly and higher efficiency. There are several substances, which have been evaluated as potential biopesticides in recent times, which include oxymatrine (an alkaloid), stilbenes found in grape cane, olive oil mill, extracts of Clitoria ternatea and stains of Talaromyces flavus. The application of biopesticides does not have side effects of concern on the environment due to its eco-friendliness. There are specific products, which have been licensed as biopesticides, although they are still being investigated for any possible health effect [8].

1.3 Uniqueness of Nanobiopesticides

According to various scientific evidences, the emergence of nanotechnology has proven to be a highly reliable tool for the formulation of novel nanocomposites suitable for curbing pest and diseases in agriculture. The nano-biopesticides have outstanding superiority over the biopesticides as well as the other traditional approaches to pest mitigation. They posses unique biodegradability, environmental friendliness, rapid action, good result, easy discharge to plants, gentle release from the vector and remarkably high efficiency. The small sizes of the nanobiopesticides also make them useful carriers [9]. More recently, various nanobiopesticides have been documented to have high efficacies against different pests, such as Bacillus sphacricus, Bacillus firmus, Trichoderma harzianum, Beauveria bassiana, and Bacillus thringicsis. These groups of pesticide have also been reported not to have negative effects on the population of microorganisms in the environment. The nanobiopesticides are prepared through various routes, with the two major being: extraction of the bioactive compound with pesticidal effect and the blending it with nanomaterials prior to inserting it into a suitable polymeric materials which act as a base support, while in the other, the active pesticidal agent produces the metallic salt with the binded nanoparticles which then hemolysis and merges into the compatible vectors including liposomes, polymer, nanosphere, nanofibers, and micelles [1].

1.4 In Vitro Nanobiopesticides Assay

Nanobiopesticides could be evaluated against specific groups of pest so as to assess their efficacies prior to their large scale applications in farmlands. The nanobiopesticides could be produce through various active pesticide based compounds together with mixing of various nanoparticles such as silver oxide, zinc oxide and oxides of aluminum. The overall toxicity of the nanobiopesticide is checked through the use of minimum inhibitory contents which employs the diffusion method based on agar well. It involves the coating of filter paper with the outer layer of nanobiopesticides as well as oral introduction to the targeted pest. Final measurement is done on the concentration of the pest that are dead and those that are alive within an interval of 40 days [2].

1.5 In Vivo Treatment with Nanobiofungicides

Nanobiofungicides can be introduced into plants in the right doses so as to ensure their protection from seasonal infections. The use of LC50 and LC90 help in the detection of the specific insects, larvae and attacks by bee. The nanobiopesticides are also used in changing environments like humidity, temperature and stresses from the environment. Under such conditions, the nanobiopesticides are applied directly as sprays in protecting the plants from attack by pests. The application of nanobiopesticides has therefore become the most efficient approach for the control of attacks by pests that transmit diseases [9].

1.6 Conclusion

There is increasing destruction of a large component of global agricultural yield due to the activities of pests. Recent studies revealed the various side effects associated with the use of chemical pesticides such neurotoxicity, Parkinson's disease, endocrine disruption, malignancies and obesity [10-19]. The emergence of nanobiopesticides has been identified as one of the most remarkable breakthrough in the field of nanotechnology. Nanobiopesticides are ecofriendly, benign with unique biodegradation potential.

References

1. 1. Abdollahdokht, D., Gao, Y., Faramarz, S. et al., Conventional agrochemicals towards nano-biopesticides: An overview on recent advances. Chem. Biol. Technol. Agric., 9, 13, 2022,...