Integrative multi-scale physiological, metabolic, and proteomic reprogramming in tomato under polyethylene...

Area of Science:

• Environmental Science
• Plant Biology
• Toxicology

Background:

• Microplastic (MP) contamination is an emerging threat to agricultural soils.
• The effects of MPs on crop physiology and molecular responses are not well understood.

Purpose of the Study:

• To investigate the concentration-dependent effects of polyethylene MPs on tomato plants (Solanum lycopersicum L.).
• To integrate physiological, biochemical, and proteomic responses to assess MP impacts under realistic soil conditions.

Main Methods:

• Tomato plants were grown in soils with 0%, 1%, or 5% (w/w) polyethylene MPs for 48 days.
• Assessed growth, chlorophyll, oxidative stress, amino acids, phytohormones, and root proteomes.
• Utilized physiological, biochemical, and proteomic analyses.

Main Results:

• Low MP exposure (1%) transiently enhanced shoot growth and chlorophyll; high exposure (5%) inhibited root growth and reduced pigments.
• Progressive oxidative stress was observed in roots, with increased H2O2 and activated antioxidant enzymes (SOD, catalase).
• Dose-dependent, organ-specific changes in amino acid profiles and phytohormone levels (ABA, SA, IAA) were detected. Proteomic analysis revealed 103 differentially expressed proteins related to metabolism and signaling.

Conclusions:

• Polyethylene MPs induce multi-scale, dose-dependent reprogramming in tomato plants.
• Responses range from transient adaptive shifts to systemic disruption, highlighting potential molecular biomarkers for agroecosystem risk assessment.