ORGANIC PRODUCTION OF URBAN GROWN LETTUCE AND ITS PROTECTION FROM HEAVY METALS

An attempt was carried out in the Vegetable Research Farm, Horticultural Department, Agriculture Faculty, University of Dohuk, during the period from September, 2012 to March, 2013 on the Zakho highway. Iceberg lettuce seeds planed in tow location in the open field (location1) and other inside the plastic house (location 2). Plants present in both locations spraying with different concentrations (0, 0.5, 1, 1.5, 2 and 2.5) g.L-1 of potassium humate, some vegetative characters and heavy metals measured. The obtained results revealed that a significant increase in vegetative characters in plants cultured in (location 2) compared with those present in location 1 and significant decrease in amount of heavy metals in plants in location 2 compared with those in location 1 especially Pb and Cu. Also experiment results manifested that spraying plants with potassium humate cased to increase in vegetative growth and decrees effect of heavy metals in plants alone and their combination with locations.