Effects of Microplastics on Agriculture: A Mini-review

Microplastics have permeated most, if not all, ecosystems including the terrestrial ones. The presence of microplastics in soil poses concerns on plants and agriculture. Microplastics alter soil biophysical properties including bulk density, water holding capacity and soil microbial interactions with water stable aggregates. The effects of microplastics on soil and plants frequently depend on the types and sizes of microplastics. This mini review presents a concise illustration of the impacts of microplastics on plants and crops. From the review, microplastics alter soil biophysical and chemical characteristics either positively or negatively depending on their types, concentrations, sizes and shapes. It reveals the ability of microplastics to affect enzymatic activities of plants which could lead to genotoxicity and oxidative damage. It unveils endocytosis of microplastics by specific plant cells as well as the uptake of microplastics via root and their accumulation and transport in plants facilitated by transpiration. This review also shows microplastics reduce root growth and seed germination at least transiently while do not seem to alter chlorophyll content. Microplastics were found to not interfere with phytoremediation of metals by the common reeds. This review highlights the need of more studies to confirm the effects of microplastics on crops and plants as the existing studies in this area are limited.