The Effect of Carbamazepine ‘CBZ’ on the Expression of Eight Stress-Related Genes in a Palestinian Local Tomato Cultivar ‘RAM’

Abstract

Tomatoes, scientifically known as Solanum lycopersicum, hold significant agricultural value globally, as well as in Palestine. Whether enjoyed fresh or processed into various forms, tomatoes serve as a vital crop. In Palestine, as well as in most other countries, tomato cultivation consumes relatively enormous amount of irrigation water. is water-dependent. As part of the Middle East region, Palestine suffers from water scarcity which necessitates searching for new approaches to supply the agricultural sector with irrigation water. One of these approaches is the use of reclaimed wastewater (RWW). Indeed, several countries in the Middle East have been already utilizing RWW in agriculture including Egypt, Jordan and Israel. One of the challenging obstacles of using RWW, as shown in several recent studies, is the presence of different pharmaceuticals and their secondary metabolites in RWW. One of these drugs is carbamazepine (CBZ) which has been found in tertiary RWW in Israel. This study aimed to investigate the effect of CBZ on the gene expression of eight stress-related genes in plants. A local tomato cultivar known as RAM was grown in a hydroponic system with two different solutions of CBZ concentrations (10nM and 200nM). Plants irrigated with tap water served as control treatment. RNA was extracted from leaves and roots samples every 24 h up to 72 hours of exposure to CBZ. cDNA was synthesized by reverse transcription and gene expression was measured using the real time rt-PCR technique The results revealed distinct patterns of gene expression in tomato leaves and roots following CBZ treatment. In leaves, a consistent upregulation of gene expression was observed after 48 hours of exposure, indicating an initial stress response followed by a return to baseline levels. Conversely, the roots exhibited no clear pattern of gene expression changes. This study is the first of its kind in Palestine to examine the impact of CBZ on the local cultivar RAM. We recommend further studies on a larger scale to understand the effect of other pharmaceuticals found in RWW on tomato and other important plants.