We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
The multifaceted mechanisms of microplastic inhibition of tomato plant growth: oxidative toxicity, metabolic perturbation, and photosynthetic damage
Summary
Researchers exposed tomato seedlings to biodegradable and conventional microplastics and investigated photosynthetic performance, metabolic disruption, and oxidative stress responses. Both microplastic types inhibited tomato growth and caused oxidative damage, with impacts on the photosynthetic apparatus and metabolite profiles, challenging the assumption that biodegradable plastics are safer for agricultural systems.
The ubiquity of microplastics (MPs) currently endangers vegetation, ecological balance, and public health. Although biodegradable plastics (BP) are potential alternatives to conventional plastics, the mechanisms underlying their effect on plants remain unclear. This study investigated the effect of biodegradable MPs (BMPs) on tomato seedlings, focusing on oxidative stress, leaf metabolism, and photosynthetic pigment synthesis. BMPs (poly (butylene adipate-co-terephthalate) (PBAT) and polylactic acid (PLA)) had a significant negative effect on tomato seedling growth compared to conventional MPs (polyethylene (PE) and polypropylene (PP)). The findings indicated that BMPs could exert stronger toxic effects on tomato seedlings than conventional MPs, as demonstrated by integrated biomarker response indices. The high degree of oxidative toxicity severely disrupts leaf metabolism, particularly the amino acid, lipid, and tricarboxylic acid (TCA) cycle. Photosynthetic pigment synthesis was inhibited more by BMPs, with key gene expression in chlorophyll (Chl) and heme pathways down-regulated, decreasing the precursor content. Exposure to BMPs Chl a and b levels were reduced by 5.25 %-43.75 % and 24.74 %-56.25 %, respectively, compared with conventional MPs. Findings from this study enhance our understanding of food safety risks associated with BMPs.
Sign in to start a discussion.
More Papers Like This
The varied effects of different microplastics on stem development and carbon-nitrogen metabolism in tomato
Researchers tested how six different types of microplastics, including both conventional and biodegradable varieties, affect tomato plant growth. All types disrupted the plants' internal structure and altered how they processed carbon and nitrogen, with PVC causing the most severe damage. Notably, biodegradable plastics like PLA and PBS were not harmless either, suggesting that switching to so-called eco-friendly plastics may not fully protect agricultural soil and food crops from microplastic contamination.
Comparative toxicological effects of traditional and biodegradable microplastics on pepper (Capsicum annuum L.): physiological and metabolomic insights
Researchers compared the toxicity of four traditional and two biodegradable microplastics on pepper plants over 60 days and found that all types inhibited growth, though through distinct mechanisms. Non-degradable polypropylene and polystyrene caused stronger growth inhibition, while biodegradable PBS microplastics triggered the most severe oxidative stress. Metabolomic analysis revealed that biodegradable and traditional microplastics each disrupt different metabolic pathways, challenging the notion that biodegradable plastics are inherently safer for agricultural ecosystems.
Mechanistic insights into the size-dependent bioaccumulation and phytotoxicity of polyethylene microplastics in tomato seedlings
Researchers investigated how polyethylene microplastics of different sizes affect tomato seedlings and found that the smallest particles (1-50 micrometers) caused the most severe damage, reducing shoot weight by 42.3% and root length by 55.1%. The study revealed that microplastic uptake and toxicity are strongly size-dependent, with smaller particles more easily absorbed and translocated through plant tissues, triggering significant oxidative stress.
Unraveling the impact of nano-microscale polyethylene and polypropylene plastics on Nicotiana tabacum: Physiological responses and molecular mechanisms
Researchers exposed tobacco plants to polyethylene and polypropylene microplastics of different sizes and found that both types suppressed plant growth in a dose-dependent manner, with polypropylene being more toxic. The microplastics disrupted photosynthesis, triggered oxidative stress, and altered hormone signaling and defense pathways in the plants. These findings demonstrate that microplastic contamination in soil can impair crop growth at the molecular level, potentially affecting agricultural productivity.
Meta-analysis reveals the combined effects of microplastics and heavy metal on plants
A meta-analysis of 57 studies found that the combined toxicity of microplastics and heavy metals on plants is driven primarily by the heavy metals, while microplastics mainly interact by inducing oxidative stress damage. Microplastic biodegradation emerged as a core factor influencing heavy metal accumulation in plants, with culture environment, heavy metal type, exposure duration, and microplastic concentration and size all playing roles.