Observations on the accumulation of five xenobiotic chemicals in phloem versus parenchyma tissues of celery

摘要

AbstractThe uptake of five xenobiotic chemicals (cinmethylin, cyanazine, hyformal, oxamyl and phenylurea) by isolated phloem strands and storage‐parenchyma tissues of celery (Apium graveolensL var.dulce) has been assessed with respect to time, substrate concentration, pH and efflux characteristics. Absorption by phloem tissue was by a diffusion‐like process which did not become saturated within the time investigated. In contrast, uptake by parenchyma tissue approached saturation within 6 h. Uptake of the various chemicals demonstrates different responses to the pH of the incubation solutions and the chemicals showed different retention characteristics within the phloem and parenchyma tissues. The use of physico‐chemical properties (logKowand pKa) to predict the behaviour of these xenobiotic chemicals within celery tissue is disc