# Phytomicrobiones: A Potential Approach for Sustainable Pesticide Biodegradation
## 3 Phytomicrobiome and Pesticide Biodegradation
### Root Microbiome  
The plant's subterranean realm is far from desolation; in fact, the root surface fosters a vibrant ecosystem, offering fertile ground and niches that provide refuge from both biotic and abiotic stresses [121]. This sanctuary serves as the backdrop for intricate plant-microbe relationships, predominantly unfolding in the dynamic realm known as the rhizosphere (as illustrated in Figure 4). This rhizosphere stage sets the scene for nurturing the expansive photomicrobione [122]. Consequently, the root microbiome stands as a close ally to the upper echelons of the phytomicrobione, conferring additional resilience to plants in the face of adverse conditions [123]. The composition of root microbiomes is a testament to their adaptability, with various soil attributes and properties, including texture, structure, and pH, as well as the identity of neighboring plant communities and the surrounding environment, intricately choreographing the assembly of these microbial communities [124; 125; 126; 127]. Previous investigations have unearthed dominant phyla in root microbiomes, revealing a diverse cast that includes Actinobacteria, Bacteroidetes, Planetomycetes, Proteobacteria, Firmicutes, Acidobacteria, Verrucomicrobia, and Gemmatimonadetes [128; 129; 130; 131]. It is worth noting that, alongside the beneficial microbes, pathogenic counterparts have also found their place within root microbiomes [132]. Consequently, the orchestration of root microbial communities, particularly during a plant's formative stages, emerges as a pivotal determinant of its future well-being [133; 134]. As we delve into the complex interplay between pesticides and the plant-associated microbiome, it becomes evident that the phytomicrobione undergoes significant transformations in response to pesticide applications across various plant compartments. This intricate dance is characterized by dynamic shifts in microbial communities, orchestrating both the degradation of pesticides and the promotion of plant growth while alleviating pesticide-related stress [135]. To provide a comprehensive view of these changes, Figure 4 offers a visual representation of microbial alterations across all phytomicrobione components. The root microbiome, endowed with remarkable diversity, emerges as a reservoir of potential pesticide degraders. Notably, organochlorine and organophosphate pesticides, ubiquitous in global agricultural practices, find functional adversaries within the root microbiome [136]. Certain microbial champions, such as _Pseudomonas putida_ KT2440 and _Pseudomonas fluorescens_, isolated from the root microbiome, have demonstrated their prowess in pesticide degradation [137]. Bacteria from the genus _Pseudomonas_ are notable contenders in this arena, harnessing pesticides as sources of carbon and nitrogen [137]. A compelling example lies in the _Fusarium_ spp. strain CS-3, isolated from the endophytic regions of plants at an acetaminophen-producing facility. This strain showcases its ability by efficiently degrading 98% of acetaminophen, with N\({}^{\prime}\)-[(6-chloropyridin-3-yl) methyl]-N-methylacetamide, 2-chloro-5-hydroxymethylpyridine, and 6-chloronicinic acid identified as prominent metabolites in this acetaminophen degradation process [47]. Intriguingly, this very _Fusarium_ spp. finds a home in the root microbiome of the tested plant, further exemplifying the potential role of the root microbiome in pesticide degradation. Chloroacetamide, an herbicide, can be degraded by the _Sphingobium_ strain, proliferating at the root zone in natural soil [138]. This pesticide can be transformed by microbial metabolism to produce 4,2-methyl-6-ethylaniline, which can be used by this microbe as a nutritional source [138]. Unraveling the enigma of the root microbiome has proven to be a complex endeavor. However, recent strides in sequencing technologies have ushered in a new era, providing invaluable insights into the root microbiota.