The effect of healthy and contaminated soil conditions on the anatomical structure and morphological parameters of cassava plants (Manihot esculenta Crantz)

Soil contamination by microplastic particles has become a serious environmental problem and affects the growth of horticultural crops, such as cassava (Manihot esculenta Crantz). This study aims to examine the impact of microplastic exposure on the anatomical structure and morphometric parameters of M. esculenta. The research methods included sampling plants and soil from healthy (TSH) and microplastic-contaminated (TTC) fields, anatomical slides of root, leaf, stem, and tuber histological sections prepared using embedding and non-embedding techniques, microscopic analysis, and morphometric measurements. The parameters measured included the thickness of the epidermis and cortex in various organs, the number of leaves, plant height, stem and tuber diameter, the number and weight of tubers, and starch and reducing sugars content. The results showed thickening of the root epidermis in TTC as a protective response, a decrease in the thickness of the epidermis and cortex in leaves and tubers, which adversely affected photosynthetic efficiency and biomass storage capacity. TTC also experienced a decline in morphometric parameters, such as the number of leaves, plant height, and stem diameter. This study suggests that soils with detectable microplastic contamination are associated with reduced M. esculenta productivity and quality, although other co-varying soil factors may also contribute to these differences. Given the observational design, these associations should be interpreted cautiously until supported by controlled greenhouse or soil characterization studies.