*Proceedings*  **A-Frame as a Tool to Create Artistic Collective Installations in Virtual Reality †**

#### **João Azevedo 1,\*, Paulo Veloso Gomes 2,João Donga 1 and António Marques 2**

Published: 26 August 2020

**Abstract:** Virtual Reality, due to its complexity and technological requirements, has a set of frictions that hinder its dissemination. The main ones can be summarized in the requirement to learn complex developing environments, like game engines, then we need to install applications, specific to each operating system and according to the means through which they can be accessed.

**Keywords:** virtual reality; A-Frame; WebVR; digital art; immersive environments

#### **1. Introduction**

The A-Frame framework, published in 2015 by Mozilla, aims to facilitate access to Virtual Reality (VR), namely through Internet browsers and all types of VR equipment. This objective is made possible by the structure on which it was developed, WebVR. It allows the creation of immersive environments that can be inhabited simultaneously by several users, even if access is made through different types of VR devices, from smartphones and personal computers to specific VR equipment, such as the Oculus Quest, Rift and HTC Vive.

As artists seek ways to express their creativity in VR, A-Frame can be a way to start creating immersive experiences without the need to learn a complex programming language or a game engine like Unity or Unreal Engine [1]. Plus, the A-Frame end results are easily delivered through the world wide web. This article focuses on the A-Frame potential to create, publish and share collective experiences of virtual immersive artistic installations. This work will demonstrate this potential through a teaching approach to this framework, and its results came from Bachelor of Arts (BA) and Master of Arts (MA) degree curricular units in a Media Art School.

#### **2. Materials and Methods**

The A-Frame core structure is a JavaScript API, an acronym for Application Programming Interface, that allows access to VR equipment through recent and popular Internet browsers, namely Mozilla Firefox, Google Chrome and Microsoft Edge. A-Frame provides a set of native elements that allow the creation of primitive geometric objects, lighting and audio systems. It is possible to import various types and formats of multimedia files, namely images, textures, videos and 3D models. All of these elements can be programmatically controlled by a simple markup language [2].

To write this code, the artist only needs a text editor; however, it is also recommended that an Integrated Development Environment (IDE) allowing the setup of a client side server is used in order to test the results locally and avoiding having to push it to an online server. However, if the developer needs to test the result online or share the code with other artists/developers, there are several

#### *Proceedings* **2020**, *54*, 47

platforms available. In the class we used Glitch and GitHub, the first was chosen for the first lessons due to its ease of use and code sharing features, the second was used in the advanced classes for the version control feature and the robust file uploader.

The fundamentals of A-Frame can be divided in four chapters: Geometry, Lightning, Animation and Interaction [3]. The classes followed this sequence since each one of these aspects grows in complexity.

In Geometry, we have the possibility to use predefined array primitives like a Box or Sphere. Each primitive has properties that define its dimension, position and materials.

The Lightning system controls the light and shadows of the scene and objects. These entities share some of generic properties of the primitives but then have the specific ones that define the type of light and shadow behavior.

The Animation component controls the movement of Geometry and Lightning entities over time. The Interaction in A-Frame is event-driven and its capable to handle keyboard/mouse, 3 and 6 degrees of freedom controllers.

#### **3. Results**

The artists of the MA degree had a creative approach but based on recognizable references, as shown in Figure 1.

**Figure 1.** (**a**) Vaporscape: A Jorge Barros project inspired by the art of the album "Floral Shoppe" by Vektroid; (**b**) A WebVR adaptation of the collective TeamLab "Forest of Resonating Lamps—One Stroke" by Luisa Guedes.

Despite the fact both courses had access to the same artistic references, most of the projects from the BA degree artists were related to the videogame culture (Figure 2). All artists from both courses fully explored the Geometry, Lighting and Animation properties, but only 8 out of 31 projects applied interaction to their creations.

**Figure 2.** (**a**) Beacon is a project by Pedro Ermida and Rúben Ferreira; (**b**) A WebVR interpretation of the Super Mario environment by Luis Alves.

#### *Proceedings* **2020**, *54*, 47

The results demonstrate that it is possible to create rich environments that can be shared over the Internet with a small learning curve when compared to game engines. Future work can evaluate the variance on the time needed to concept, develop and distribute this projects with other creative platforms.

**Author Contributions:** Conceptualization, J.A.; methodology, J.A. and P.V.G.; writing—review and editing, J.A.; P.V.G. and J.D.; supervision, A.M. and J.D.; project administration, A.M. and J.A. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research received no external funding.

**Conflicts of Interest:** The authors declare no conflict of interest.

#### **References**

© 2020 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).


**5. New Localization Module: GNSS/SLAM Fusion**

One of the research lines that our group wants to develop in the future is the fusion of SLAM algorithms with GNSS-based systems. The motivation for this fusion is the complementarity of both localization systems since SLAM algorithms need relatively close landmarks to extract positional information—which can cause occlusions and multi-path problems to GNSS positioning—while GNSS systems work better in clear areas that are challenging for SLAM algorithms because of landmark scarcity. As a starting point for our future research and in order to demonstrate the versatility of our framework, we developed a new localization system based on GNSS/SLAM fusion. Figure 7 shows the ROS nodes scheme of our new localization module, and Figure 8 details its connection with the rest of the system. In our solution, we fuse the positions obtained by the two systems using a Kalman filter in which these positions will be considered asynchronous observations and the odometry is used as a control signal in the prediction phase of the filter. This module allows off-map localization, so it would be difficult to integrate it with the navigation stack but its integration is straightforward using our framework. We next describe each subsystem shown in Figure 7.

**Figure 7.** ROS nodes scheme that shows the combination of subsystems that make up the new localization module that will be tested using our framework. This scheme corresponds to the "global navigation satellite system (GNSS)-a Monte Carlo localization (AMCL) fusion" node shown in Figure 8. The "Kalman filter" node uses odometry as a control action, and odometry-GNSS and pose AMCL as observations.

**Figure 8.** *ROS nodes* scheme that shows the second implementation of our framework which incorporates our novel GNSS fusion localization algorithm. This new implementation has been completed just substituting the previous localization module and adding the GNSS sensor driver. We show these modifications with solid fill in the nodes added or replaced with respect to Figure 3.

#### *5.1. AMCL Subsystem*

One of these subsystems is AMCL described in the previous section. To properly implement the fusion, we need to pay attention to the variances that this subsystem provides, associated to each estimated pose (Section 4.2.1) because they provide information about the confidence of the solution. This information will be used by the Kalman filter in the correction step, and it also will be useful for the integrity monitoring system.

#### *5.2. GNSS Subsystem*

The GNSS system provides geolocalization in world coordinates (world frame) but to perform the fusion with the subsystem described above we need to convert the global coordinates to map coordinates. For this we use the navsat node available in the ROS robot localization package [41]. In the initialization step, this node receives a position expressed in the frame we want to use as reference—in our case the position calculated through AMCL depicted as a green dotted line in Figure 7—and generates a *T* transformation between the pose in world frame to the map frame. Then *T* is applied to all the measurements made by the GNSS. By using only the navsat node, we could only read the GNSS fix and generate a 2D position in the map frame, but without orientation. To overcome this issue we generated a new ROS node called odometry GPS (Figure 7) in which we receive the velocity fix provided by the GNSS and the position and the *T* calculated by navsat. The output of this node is the orientation in the map frame, obtained using the velocity vector (provided by GNSS velocity fix) and the transform between the global frame and the map frame given by the navsat node.


**2.2.2 Large microcosm system**

194 Aquaculture

refrigerated at 4°C until they were needed. Copepod eggs were taken out the 100 ml flask and placed in a 500 ml transparent flask with seawater at 35 ppt and 28ºC under a 12 hours light:dark period. No aeration was needed during the 48 hours hatching period. After hatch, *A. tonsa* were fed to the snook larvae. Feeding densities varied depending on the

All the experiments were conducted using two independent experimental systems: small

The small microcosm system (System A) was a self-contained recirculating system (Rana, 1986), which allowed several different experiments to be run at the same time, with the appropriate replication.. The system was made of transparent plexiglass, and contained 48 2-L tanks (Figure 1), The system dimensions were 1.25 m in length by 70 cm in width by 20 cm in height. The individual tank dimensions (Figure 1) were 12x10x20 cm, with an opening to allow water exchange 17.5 cm from the bottom, which was covered by a mesh screen (75 µm). In addition to the larval tanks, the system included two sumps, a 140 liter sump (filled with biofiltration beads) and a 120 liter sump (with a fluidized bed and a carbon filter). Air stones, were placed in both sump and a pure oxygen ceramic stone was also in the second sump, in order to keep the dissolved oxygen levels between 8 to 10 mg/L. Flow rates within the larval tanks was individually regulated through a drip valve. Flow rates varied between tanks depending on the experimental requirements. The tank recirculating system was based on an overflowing system, with a drip valve on the inflow and a 75 µm mesh rectangular opening for tank outflow. For the first 3 days after hatching, a transparent

Fig. 1. System A (Microcosms) and individual tank dimensions

experiment.

**2.2 Larval rearing systems**

and large microcosm systems.

**2.2.1 Small microcosm system**

The large microcosm system (System B) was built in 2005 to provide additional replicated experimental tanks. The water volume in the System B tanks (6L) was 3 times the water volume of the System A tanks (2L) and was used to conduct simultaneous trials to compare the influence of increased water volume on larval survival. System B tanks were placed in a green bottom fiberglass raceway, where individuals tanks where maintained in a water bath (Figure 2). Twelve (6 l) tanks shared the same filtration system, which included a fluidized bed, a moving bed bioreactor, UV, and a protein skimmer. The system had two 300-litre sumps under the raceway, where the filtration system was set up. Air stones were placed in each tank to keep dissolved oxygen at desired levels. Water heaters were placed in the raceways to maintain constant temperature.

Fig. 2. Larval rearing System B. Full system and individual rearing tanks (left to right)

Inflow water was regulated individually per tank, and outflow water passed through a 75 µm mesh standpipe, draining into a common drain channel (Figure 2, middle picture) leading to the first sump. Slight aeration was also supplied to the individual tanks. A 25% water exchange was carried out every week. Like in the microcosms, water quality (temperature, salinity, dissolved oxygen and pH) was checked three times a day (every five hours). Nitrite, ammonia and nitrate were monitored weekly.


**Author details**

Matthew Terzungwe Tion1 \*, Kenneth Ikejiofor Ogbu2 and Felix Kundu Shima3

1 University of Agriculture, Makurdi, Benue State, Nigeria

2 Federal College of Animal Health and Production Technology, National Veterinary Research Institute, Vom, Plateau State, Nigeria

3 Ministry of Agriculture and Natural Resources, Makurdi, Benue State, Nigeria

\*Address all correspondence to<EMAIL_ADDRESS>
© 2023 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


2.3.1. Whole Genome Sequencing

The aboveground parts of KDML105, DH103, and CSSL104 rice plants were collected at fourteen days after germination. Rice genomic DNA was extracted using a Genomic DNA Mini Kit, 'Plant' (Geneaid, New Taipei City, Taiwan). Genomic DNA libraries were prepared for sequencing by using an Illumina genome analyzer (Illumina, San Diego, CA, USA) with Illumina HiSeq3000's protocol. For genome analyses, the sequence reads were classified into specific categories using the pipeline developed by Missirian et al. [16]. The rice genomic sequence from the Rice Genome Annotation Project database [17] was used as a reference genome [18] to map the sequence reads. The raw reads were submitted to GenBank at the NCBI under BioProject no. PRJNA659381. Bioinformatic tools were used to compare the genome of CSSL104 with the KDML105 rice genome to identify loci containing di fferent single nucleotide polymorphisms (SNPs). These loci may contribute to the drought-tolerance phenotypes of CSSL104. The genome comparison first started by discarding all SNPs shared by both CSSL104 and KDML105. The remaining di fferential SNPs were counted within a sliding window of 5000 background nucleotides. To visualize the chromosome plots with the marks of di fferent SNPs' loci, the window region containing more than 100 SNPs in CSSL104 with di fferent nucleotides from KDML105 was marked as a blue line on the chromosome plots. The analysis of the locations of SNPs in the candidate genes was analyzed.


9. Indications

Indications for treatment with plasma-driven RF include focal lipodystrophy with mild to moderate soft tissue laxity. Post-bariatric patients can be treated if the need for skin contraction is less than 33% and if pendulosity of the tissue is mild. If the patient's focus is skin quality without excision, or improvement in poor soft tissue tone, the addition of this energy can improve outcomes. Patients who have given birth and want to restore their physique can also be helped, but diastasis recti can only be slightly improved with subcutaneous RF stimulation of the lax fascia. Breast lifting can be achieved to a significant degree, but the technique works best in patients with grade I and II ptosis and size C cup or less. The addition of a suspension suture can improve the outcome, especially for the subareolar and lower pole contour. Other popular treatment regions include the lower face and neck, upper arms, axilla, bra roll, abdomen and pubis, flanks, and circumferential thighs and knees.


*4.4. Inborn Errors of Immunity with Immune Dysregulation*

Bi-allelic loss-of-function variants in *TET2* in humans have been associated with immunodeficiency and autoimmune lymphoproliferative syndrome (ALPS)-like phenotypes with remarkable predisposition to lymphoma [84]. TET2 is a crucial epigenetic regulatory factor in hematopoietic cells, facilitating demethylation by oxidizing 5-methylcytosine (5mC) to 5-hydroxymethylcytosine (5hmC) and other oxidation products. Loss-of-function mutations in TET2 are responsible for DNA methylation increases in hematologic cells, thus accounting for the failure of the controlled development of B cells and the expansion of double-negative T cells [85]. In Tregs, TET is implicated in the stability of Foxp3 molecules. The haploinsufficiency of TET2 is related to hematological neoplasia. However, it should be mentioned that TET2 mutations also occur in healthy subjects with clonal hematopoiesis, implying that they are sufficient to induce cancer alone [86,87]. Extrinsic factors, namely infections through hyperinflammation, seem to be co-factors in carcinogenesis.

The activity of activation-induced cytidine deaminase (AID) is hampered in TET2-/ mice, leading to abnormal demethylation. Altogether, these changes impair the transcription of genes critical for germinal center exit, antigen presentation and the differentiation of germinal center B cells, concurring with the development of diffuse large B-cell lymphomas. Therefore, it is conceivable to presume that TET2 has a crucial role in cell proliferation and differentiation [87].

TET proteins are also essential for specific points of B cell development, such as the transition from pro-B to pre-B and the differentiation of plasma cells [88].


**3. Li fi –transmitter and receiver**

The operational procedure of Li-Fi is very simple, it transmits binary 1, if the LED is in on condition, if the LED is off, it transmits a binary 0. The switching of LEDs between on and off positions can be implemented very quickly, which gives wonderful chances for data transmission. A controller which is used to program the LEDs and some LEDs are mainly needed. To implement the Li-Fi technology, it is required to just vary the LED's flicker rate based on the data we need to encode. All the data on the internet will be streamed on one end to a lamp driver when the LED is switched on the controller which converts the digital data in form of light. At the receiver end, the received signal is converted back to original signal with the help of a light sensitive device (photo detector). This method of wireless transmission of data using rapid pulses of light is technically denoted as Visible Light Communication (**Figures 2** and **3**) [5].

**Figure 2.** *Top view of Li-Fi transmitter and receiver.*

**Figure 3.** *Bottom view of Li-Fi transmitter and receiver.*

#### *IoT Applications Computing*

Light based Wi-Fi is called as Li-Fi. It uses light signal instead of radio waves for data transmission. Li-Fi uses transceiver-fitted LED lamps instead of Wi-Fi modems. Transceiver-fitted LED lamps can be used to light a room as well as transmit and receive information [5]. Power supply is used to provide power to the transmitter and receiver section. Data stored in the controller is transmitted through a Li-Fi LCD display that is used to check whether the data is transmitted and received. Microcontroller is used to control both transmitter and receiver sections. A controller used in both transmitter side and receiver side. Using Proteus software tool program written to microcontroller. Li-Fi is a term used to describe the visible light communication technology applied to high speed wireless communication (**Figures 4** and **5**).

#### **Figure 4.**

*Working module of Li-Fi Tx and Rx via LED.*

**Figure 5.** *Li-Fi transmitter.*

*Vehicle Collision Avoidance System Using Li-Fi DOI: http://dx.doi.org/10.5772/intechopen.98616*


*Review* **Carbon Dots for Killing Microorganisms: An Update since 2019**

**Fengming Lin , Zihao Wang and Fu-Gen Wu \***

State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, 2 Sipailou Road, Nanjing 210096, China **\*** Correspondence<EMAIL_ADDRESS>
**Abstract:** Frequent bacterial/fungal infections and occurrence of antibiotic resistance pose increasing threats to the public and thus require the development of new antibacterial/antifungal agents and strategies. Carbon dots (CDs) have been well demonstrated to be promising and potent antimicrobial nanomaterials and serve as potential alternatives to conventional antibiotics. In recent years, great efforts have been made by many researchers to develop new carbon dot-based antimicrobial agents to combat microbial infections. Here, as an update to our previous relevant review (C 2019, 5, 33), we summarize the recent achievements in the utilization of CDs for microbial inactivation. We review four kinds of antimicrobial CDs including nitrogen-doped CDs, metal-containing CDs, antibioticconjugated CDs, and photoresponsive CDs in terms of their starting materials, synthetic route, surface functionalization, antimicrobial ability, and the related antimicrobial mechanism if available. In addition, we summarize the emerging applications of CD-related antimicrobial materials in medical and industry fields. Finally, we discuss the existing challenges of antimicrobial CDs and the future research directions that are worth exploring. We believe that this review provides a comprehensive overview of the recent advances in antimicrobial CDs and may inspire the development of new CDs with desirable antimicrobial activities.

**Keywords:** antibacterial; bactericidal; disinfection; carbon nanodots; carbonized polymer dots

**Citation:** Lin, F.; Wang, Z.; Wu, F.-G. Carbon Dots for Killing Microorganisms: An Update since 2019. *Pharmaceuticals* **2022**, *15*, 1236. https://doi.org/10.3390/ph15101236

Academic Editor: Dimitris Tsiourvas

Received: 29 July 2022 Accepted: 20 September 2022 Published: 8 October 2022

**Publisher's Note:** MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations.

**Copyright:** © 2022 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/).


**8.4 Water and environment**

Morphology of nano fiber materials is attracting researchers due to numerous applications in environmental and water related issues in recent developments. Membranes of nano fibers developed from electrospinning technique shows greater prospective in waste water treatment and recycling. Many water treatment functionalities such as separation, adsorption, photo catalysis and antimicrobial activities can be treated effectively by nano fiber membranes Fiber mats prepared from nano fibers act as best filtration membranes that minimizes pressure drop with better efficiency than conventional mats. The contaminants in water and air were absorbed from the membranes of nano fibers with large surface to volume ratio and shows an increment in the life time of these mats [54].


**4. Conclusions**

The use of robotic technology as support for the rehabilitation of patients with paraplegia is a very important tool, which should be considered as part of recovery plans, improving the quality of life of users who require them. However, it is important to note that although it has great advantages for users, the cost of these exoskeletons is so high that it becomes difficult to be provided to all those patients who need them, besides there are also some models that are in early preliminary studies to be still considered for use in regular clinical practice.


**1. Introduction**

Growing attention is being paid to the proper functioning of ecosystems [1,2]. This is due to numerous initiatives which have been undertaken globally to make the population aware of the need to protect soils and for their sustainable management. One of the first of these initiatives was the announcement of the European Soil Health Card, which has made both the population and policy makers aware of the significant role of the soil environment, and has introduced a new term, 'environmental services', which was later changed to 'ecosystem services' [3]. The concept of soil quality and health, often used interchangeably, is becoming increasingly recognized worldwide [4–6]. Legaz et al. [6] and Bünemann et al. [7] define 'soil quality' as the capability of soil to function in

the framework of ecosystems, and also as land management and promotion of the biodiversity and health of plants and animals. According to Cardoso et al. [5] and Veum et al. [8], the term 'soil health' highlights the fact that soil is a live and dynamic being whose functions are determined by the diversity of living organisms. Therefore, the physical, chemical, and biological properties of soil may change according to biotic and abiotic factors, which consequently affect its functions and ecosystemic services [3,9].

Apart from elements such as profile morphology, physical and chemical properties, and microclimate, the microbiological activity of soil is another principal factor affecting its fertility [10]. Microorganisms and enzymes determine the transformation of organic matter introduced into soil, influence the humification process, and play a key role in the biogeochemical cycles of many macro- and micro- elements [7]. They are key participants in most of the important cycles, including carbon, nitrogen, phosphorus, and sulfur circulation. It is mainly the biogeochemical cycles of these elements that determines the quality of the natural environment, including the soil environment [9]. The role of microbes is invaluable in the transformation of postharvest residues, as well as natural and organic fertilizers [11,12], the detoxication of organic contaminants in soil [13,14], minimizing the prevalence of pests and pathogens [11], and finally, in establishing symbiotic systems with plants [15]. The enormous importance of microorganisms for the soil environment and their high metabolic activity are confirmed by the fact that the microbial biomass of soil accounts for approximately 85% of the total biomass of all living organisms colonizing this environment [11].

The main factors which affect the development of soil microorganisms include the abundance of organic and mineral colloids in the soil, the climate and microclimate, oxidation associated with humidity status [16–19], soil pH [20,21], soil tillage and plant cultivation systems [22–24], and fertilization systems [25]. An inseparable element in this case is soil temperature, which is affected by the climate and microclimate [16,26,27]. Significant are also contamination with heavy metals [28,29], various hydrocarbons [30–32], plant protection agents [33–35], and dioxins, as well as the salinity level [36], all of which determine the proliferation of various microbial communities for which an increase their diversity may reduce soil fertility and, ultimately, influence soil productivity [37].

All the aforementioned parameters determine the development of not only microorganisms, but plants as well. The connection between both of these groups of organisms is of the utmost importance, e.g., in the case of symbioses of certain bacteria and fungi species with plants. Noteworthy are also the microorganisms that live in association with plants and produce growth hormones, bind atmospheric nitrogen, and protect plants against pathogens. An important role is also ascribed to the microbes classified as plant growth-promoting rhizobacteria (PGPR) [38]. On the other hand, apart from bacteriorrhiza, mycrorrhiza, and microbe associations with plants, we cannot observe a beneficial effect of root secretions on microorganisms or a positive impact of root systems on the physical properties of soil, as it serves the function of drainage, which is essential for appropriate soil oxygenation [27,39]. Root secretions, which may contain organic acids, amino acids, carbohydrates, vitamins, and metal ions, modify the microenvironments of the rhizosphere [40]. They release ions, oxygen, water, and carbon-containing compounds [41]. They may both stimulate and inhibit the development of a soil microbiome [42], and act both as repellents [43] and attractants [44]. Volatile organic compounds (VOCs) emitted by soil microorganisms can affect root growth. Bacterial volatile compounds (BVCs) are used as a source of nutrients and information in plant–bacterium interactions [15]. Such interactions are the strongest in the rhizosphere [7,45], which is colonized by 10 to 100 times more microorganisms than the sphere that is distant from plant roots [46]. The beneficial bacteria of the rhizosphere compete with other microorganisms for organic compounds and colonize plant roots [47]. Microorganisms colonizing this microecosystem are affected by the root secretions of particular plant species and form specific microbial communities [48]. The 16S amplicon sequencing analysis, a small subunit ribosomal ribonucleic acid (SSU rRNA), is an important element in biological quality assessments of soil, as it may provide answers about the response of individual taxa to variable factors in different agricultural

ecosystems [49]. Despite the severity of the problem, investigations into the effects of plants on soil bacteria based on next-generation methods are still scarce.

The complex nature of the active rhizosphere has become a premise for undertaking a study aimed at determining the effect of a crop and its cultivation regime on changes in the soil microbiome. Three plant species were used in the study: winter wheat, winter rape, and field pea; these species were cultivated on soil with a similar fraction size. Analyses were performed to determine the structure and diversity of microorganisms and the activity of the soil enzymes participating in the metabolism of carbon, nitrogen, phosphorus, and sulfur. The coupled use of microbiological, biochemical, and physicochemical parameters form the basis for a better understanding of the interactions between the rhizosphere, microorganisms, and plants, which is extremely important from the viewpoint of soil fertility.


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### *Edited by Snježana Topolovec-Pintarić*

Plant pathogens, the causal agent of infectious plant diseases, influence our lives more than just as an economic impact through yield lost. The study of plant pathogens has given rise to the development of new sciences, new technologies for plant breeding, and the agrochemical industry for pesticide developments. Yet, all our actions and efforts to suppress or eradicate them constantly pressures these various organisms to evolve and adapt for survival. Therefore today, when facing climate changes, accelerated transport of plants and plant products, and world population growth, we have to ask quo vadis phytopathology. Like Alice in Wonderland "If we wish to go anywhere we must run twice as fast as that" so we need to constantly broaden our knowledge. However, today's literature abounds with knowledge about plant pathogens. Hence, this book intends to present to the reader all the latest material and knowledge about plant pathogens, changes or refinements in plant disease epidemiology, and new approaches and materials used for plant pathogen control. Hopefully, this book will be of interest to those working within the field and looking for an up-to-date introduction. We hope it also interests students and thereby, will influence the future development of phytopathology and our better coexistence with plant pathogens.

Published in London, UK © 2020 IntechOpen © Lunasix / iStock

Plant Diseases-Current Threats and Management Trends

Plant Diseases

Current Threats and Management Trends

*Edited by Snježana Topolovec-Pintarić*