Effect of Gamma-Irradiated Ceramic Wastewater Sludge on Photosynthetic Pigments of Phaseolus Vulgaris L. (Cv. Valentino and Cv. Nebraska) Plants

Abstract

The common bean plant is a highly polymorphic species, annual herb, erect and bushy, 20–60 cm tall, or twining with stems 2–3 m long, with a taproot and nitrogen nodules which the bacteria could convert nitrogen gas and stores it in the common bean plant roots. Leaves are alternate, green, or purple, trifoliolate, stipulate, petiolate, markedly pulvinus at base; leaflets ovate, entire; acuminate, 6–15 cm long, 3–11 cm wide. Many soils have been contaminated with several pollutants, mostly arising from wastes of human activities such as the use of pesticides, sewer sludge, mining and smelting sources, radioactive substances, and industrial dischargers. These different contaminants can degrade the soil and cause a negative impact on the plant due to disturbing nutrient cycling within ecosystems and subsequently human health. This study aimed to elucidate the mechanism by which the plant may cope with heavy metals stress represented in this study in the form of industrial ceramic wastewater sludge. And, evaluating the role of gamma radiation on ceramic wastewater sludge, could reduce the percentage of the endogenous levels of heavy metals in ceramic sludge. This study investigates the influence of Photosynthetic pigments of the two common bean cultivars Valentino and Nebraska which are grown in light soil clay/sand (1:1) incorporated with ceramic-wastewater sludge (CWWS) non-irradiated (1% and 2%) and gamma-irradiated (2.5 kGy and 10 kGy) for 30 days. The application of non-irradiated CWWS induced an elevation in the contents of chlorophylls a, b, and carotenoids in the two cultivars while a reverse trend was observed in the leaves of both cultivars treated with gamma irradiated CWWS.