**6. Biocontrol product trends and innovative technological developments for antiviral and insect-pest management**

The trends of plant EO for antiviral property and insect-pest management under the sustainable agricultural crop production were not widely accepted when compared with the synthetic chemicals. The interactions of host and virus have developed

#### *Perspective Chapter: Perspectives on Pathogenic Plant Virus Control with Essential Oils… DOI: http://dx.doi.org/10.5772/intechopen.104639*

resistance to bioactive compounds [51, 81]. The advantages of using natural products including; agriculture product safety, reduced levels of plant viruses and insect pests, improved product quality as well as value and guaranteed market access. However, these advantages depend on the physical factors (e.g., agro-climatic zones, seasons, and crops) and biological factors (e.g., biotransformation population dynamics of microorganisms, microbial degradation). Therefore, product development responds to a wide range of applications and is suitable for use in large-scale agricultural fields. Agriculture 4.0 policy plays an important role in the development of the preparation and processing of plant materials for the effective production of natural substances, crop protection, and successful pest management.

Several bioactive compounds of plant EOs were confirmed and classified as generally recognized as safe (GRAS) by the United States Food and Drug Administration (FDA) and the United States Environmental Protection Agency (EPA), which reported in the medical and agricultural applications. For example, thymol and carvacrol as the main compounds were isolated from winter savory (*Satureja montana* L., Lamiaceae) and showed the direct inactivation of TMV and CMV [82]. Sun et al. [83] reported that the plant-derived compound of eugenol showed effective antiviral activity of *Tomato yellow leaf curl virus* (TYLCV: *Begomovirus*, *Geminiviridae*) and induced the salicylic acid (SA) biosynthetic pathway. The main bioactive compounds of lemon-scented gum (*Eucalytpus citriodora* Hook., Myrtaceae) and fennel include eucalyptol, D-limonene, and L-limonene and eugenol in clove buds can inhibit PLRV infection [42]. Three monoterpenes (thymol, carvacrol, and p-cymene) that were extracted from charlock (*Sinapis arvensis* L., Brassicaceae), balangu (*Lallemantia royleana* Benth., Lamiaceae), and small fleabane (*Pulicaria vulgaris* Gaertn., Asteraceae) had an inhibitory effect against *Herpes simplex virus* type 1 (HSV-1: *Simplexvirus*, *Herpesviridae*) [84]. However, differences of viral types and componential diversity of plant EOs were affected the biological mechanisms in the antiviral and insecticidal activities.

Limitations of various conventional techniques for detection and analysis of bioactive compounds are separated sampling, adsorbent preference, and taking a long time. It is also requiring additional equipment such as adsorbent traps, laboratory-based molecular assays, and gas chromatography–mass spectrometry (GC–MS). While the applications of noninvasive methods and innovative technologies such as E-nose, gas chromatography–flame ionization detector (GC-FID), proton-transfer-reaction mass spectrometry (PTR-MS), proton-transfer-reaction–time of flight–mass spectrometry (PTR-TOF-MS), electrolyte-insulator–semiconductor (EIS) sensor, and image analysis systems had potential for specific compound analyses [85, 86]. The other indirect-plant disease identification methods by morphological and physiological changes can be applied in the field with smart technologies. Digital camera technologies of visible/RGB (red, green, and blue) imaging-based methods can be applied for plant phenotyping and monitoring during the growing season [74]. The hyperspectral (HS) imaging-based systems were used for TSWV detection at an early stage, which Wang et al. [87] showed successfully detected with 96.25% accuracy and the economic impact of plant viruses such as TMV [88], *Grapevine vein-clearing virus* (GVCV: *Badnavirus*, *Caulimoviridae*) [89], *Tulip breaking virus* (TBV: *Potyvirus*, *Potyviridae*) [90], and *Potato virus Y* (PVY: *Potyvirus*, *Potyviridae*) [91] similarly operated. In the same way, the alternative viral detection methods before the appearance of visible symptoms by chlorophyll fluorescence (ChlF) imaging can be potentially used for CMV [92], TMV [93], *Pepper mild mottle virus* (PMMoV: *Tobamovirus*, *Virgaviridae*) [94], *Sweet potato feathery mottle virus* (SPFMV: *Potyvirus*, *Potyviridae*), *Sweet potato chlorotic stunt virus* (SPCSV: *Crinivirus*, *Closteroviridae*) [95], and *Turnip crinkle virus*

#### **Figure 7.**

*Read-out platforms of smartphone applications and parallel advancements by different methods for plant disease diagnosis and detection.*

(TCV: *Carmovirus*, *Tombusviridae*) [96]. Additionally, the other smart technologies and high-throughput techniques have highly efficient agriculture analysis and can be integrated and applied with the innovation of artificial intelligence (AI) such as thermography [97], Raman spectroscopy (RS) [98], phytohormone biosensing and active remote sensing methods of radio detection and ranging (RADAR), and light detection and ranging (LiDAR) [99].

Plant EOs and their active compounds will be applied after preliminary detection and analysis by easy-to-use smart technologies in which the collected data was automated and real-time report. Therefore, the integration of different innovative technologies is providing for crop protection. Especially with smartphone applications that combine innovative technologies between imaging, telecommunications, and computing technologies including modern smartphones technologies, and smartphone-based volatile organic compound (VOC) sensor systems are interesting (**Figure 7**). Several free downloads of smartphone-based AI applications (crop diagnostics tools) can be applied with imaging and phenotyping for plant pathogen and insect pest identification such as Leaf Doctor [100], Pestoz, Plantix, PlantVillage Nuru, Agrio, PlantSnap, CropsAI, Plants Disease Identification, DoctorP, Crop Doctor, Purdue Tree Doctor, Leaf Plant Tech, and Tumaini. Li et al. [101] reported that the developable smartphonebased VOC fingerprinting platform with nanosensors and conventional chromogenic dyes was successfully detected the leaf volatile emissions at the early infection stage of *Phytophthora infestans* on tomato plants with the high detection accuracy of >95%. Similarly, several plant viruses were correctly detected by automated mobile apps such as *Banana bunchy top virus* (BBTV: *Babuvirus*, *Nanoviridae*) [102] and *Cassava brown streak virus* (CBSV: *Ipomovirus*, *Potyviridae*) [103].

### **7. Plant EO future challenges and perspectives under agriculture 4.0**

The quality and stability of natural products depend on the quality of raw materials, extraction method techniques, and conditional storage. Therefore, the

#### *Perspective Chapter: Perspectives on Pathogenic Plant Virus Control with Essential Oils… DOI: http://dx.doi.org/10.5772/intechopen.104639*

efficacy and role of natural extracts for antiviral and insect-pest management need to be considered as valuable and renewable processes. The research development of Agriculture 4.0 will improve the utilization of bioactive compounds. Crop protection under modern biotechnology collaborates innovative technologies in artificial intelligence to be used in the process design of extraction equipment and data storage. However, the success of Agriculture 4.0 will require policy and research support. Raising awareness of the value of natural products, the conservation of biodiversity and human health, and environmental safety will lead to the acceptance of agricultural products. This will create sustainability in modern farming systems.

The big data applications in smart farming can help the farmers in agricultural planning and executing activities to crop yield management. For example, integrated innovative technologies with software have the potential in detecting and monitoring plant diseases and insect pests. The smart network applications combined with the various push factors include general technological developments (e.g., IoT, AI, and agri-tech companies), sophisticated technologies (e.g., global navigation satellite systems, remote sensing, robots, and UAVs), data generation and storage, digital connectivity, and innovation possibilities that will enable efficiency for planning and operating agricultural works related to the pull factors (e.g., business and public drivers) [104]. This knowledge can be applied in the stages of the data and supply chains of plant EOs as follows: data capture, data storage, data transfer, data transformation, data analytics, and data marketing. Moreover, smart technical challenges and environmental treads related to security and safety as well as sustainability will be created, solved, and developed for big data in smart farming. The important issues for natural product development by innovative start-up companies are lacking many references for efficiency improvement, reliable quantitative analysis, and farmer's acceptance. The easily accessible platforms in real-time information are important for the benchmarking and modeling of business in supply chain scenarios and social media platforms. Integrated different players and partners in the short supply chains between the farmers and suppliers have potential management rather than integrated long supply chains. These operation models will reduce factors of the privacy and security of data ownership by the intelligent processing of management information systems. All of these are related to sustainable integration and smart-business models especially empower farmers and collaboration in all processes of supply chains through the openness of smart platforms. Consequently, the Plant EO future challenges under Agriculture 4.0 policy will be developed by the knowledge-based and knowledge engineering systems of integrated innovative technologies. The ultimate goals of developable natural product-based plant EOs and their active components with the various mechanisms of action will be designed for the farmers. As a result of these, the vital challenges will improve sustainable agricultural policies and strategies in the different crop systems under Agriculture 4.0.

### **8. Conclusion**

The outbreak and resistance problems of plant pathogenic viruses and insect vectors to natural and chemical products have tended to increase. Farmers need safe and high-quality products to solve their problems. Several recent innovative technologies to develop and improve environmentally friendly products for antiviral and insect-pest management can be used to effectively control production quality under large-scale agricultural fields. Agriculture 4.0 is a modern model that can improve

the efficiency of natural substances with the research development of extraction techniques and bioactive quality testing to promote and build farmers' acceptances. However, the modern agricultural system must be supported and cooperated by not only the government but also the public sectors to push the policy toward sustainable concrete practice for the highest benefit to environmentally friendly and humanity.
