Environmental risk substances in soil on seed germination: Chemical species, inhibition performance, and mechanisms

Nowadays, numerous environmental risk substances in soil worldwide have exhibited serious germination inhibition of crop seeds, posing a threat to food supply and security. This review provides a comprehensive summary and discussion of the inhibitory effects of environmental risk substances on seed germination, encompassing heavy metals, microplastics, petroleum hydrocarbons, salinity, phenols, essential oil, agricultural waste, antibiotics, etc. The impacts of species, concentrations, and particle sizes of various environmental risk substances are critically investigated. Furthermore, three primary inhibition mechanisms of environmental risk substances are elucidated: hindering water absorption, inducing oxidative damage, and damaging seed cells/organelles/cell membranes. To address these negative impacts, diverse effective coping measures such as biochar/compost addition, biological remediation, seed priming, coating, and genetic modification are proposed. In brief, this study systematically analyzes the negative effects of environmental risk substances on seed germination, and provides a basis for the comprehensive understanding and future implementation of efficient treatments to address this significant challenge and ensure food security and human survival. The proliferation of environmental risk substances in soil posed a grave threat to crop seed germination worldwide, jeopardizing food supply and security. Heavy metals, microplastics, petroleum hydrocarbons, salinity, phenols, essential oils, agricultural waste, antibiotics, detergents, etc., are among the substances significantly impeding seed germination, with complex inhibition mechanisms such as hindering water absorption, inducing oxidative damage, and damaging seed cells. To address this challenge, strategies like biochar/compost addition, biological remediation, seed priming, coating, genetic modification are recommended. This review underscored the urgent need for effective interventions to safeguard food security and human survival.