EFFECT OF TREATED SEWAGE WATER ON VEGETATIVE AND REPRODUCTIVE GROWTH OF DATE PALM

The effect of treated sewage water on the vegetative and reproductive growth of date palms was assessed. Leaves and fruits samples were coll ected from locations irrigated with treated sewage (TSW), desalinised, and well water. Samples were analysed for their calcium (Ca), magnesi um (Mg), iron (Fe), lead (Pb), copper (Cu), and zinc (Zn) content by a tomic absorption spectrophotometry and for sodium (Na) and potassium ( K) by flame photometry. The Mg, Fe, and Zn content of fruits and Na in the leaves were not found to be significantly different. Treated sewa ge water from University campus utilities significantly increased the Na, K, and Cu and reduced Ca in leaves and Zn in fruits of date palms. But no significant effect was observed on the K, Ca, Mg, and Na conte nts in fruits of the same palms. The different concentrations of Ca, M g, Fe, and Zn in the fruits of date palms grown along the same TSW lin e were attributed to variations in the soil; however, those in Pb cont ent of leaves could be attributed to motor vehicle combustion. The gen eral trend indicated that fruits contained higher K, Na, and Fe conten ts, but lower Ca, Mg, Cu, Zn, and Pb contents than the leaves. Further more, leaves of date palms irrigated with desalinised and well water c ontained higher Ca and Zn, but lower K, Mg, Na, Cu, Fe, and Pb content s than those of palms irrigated with treated sewage water. Desalinised water reduced the K, Ca, Na, and Zn contents, but it increased the Mg , Fe, Cu, and Pb content of leaves compared to well water. None of the examined metals were found to reach toxic level to man or plant.