Plant Health Effects of Terrestrial Plastisphere

Microplastic contamination in terrestrial ecosystems may result from numerous sources, including plastic-mulching films, materials used in greenhouses, irrigation tools, municipal solid waste, wastewater treatment facilities, and soil amendments such as composts. Due to their specific physicochemical characteristics, microplastics may effectively carry microbes and environmental materials while promoting the formation of biofilms, allowing them to form the “plastisphere,” a type of microecosystem. The plastisphere is a habitat for a variety of invasive and pathogenic microbial species. Furthermore, beneficial microbial communities in the soil that are crucial for the cycling of nutrients and the prevention of plant diseases may be affected by plant pathogens in the soil plastisphere, which would have an additional negative effect on plant health. The comprehensive understanding of the microbial community within the plastisphere, particularly its effects on soil–plant interactions and the mechanisms regulating microbial communities in contaminated rhizosphere soils, is still limited. This chapter highlights the diversity of the terrestrial plastisphere, its implications for soil properties, and its potential ecological risks, including dissemination of plant pathogens and weakening of plant defence mechanisms.