Study of soil bacterial and crop quality irrigated with treated municipal wastewater

In arid and semi-arid regions، wastewater reuse has become an important element in agriculture. However، irrigation with this resource can be either beneficial or harmful، depending on the wastewater characteristics. The aim of this research was to investigate the soil bacterial and crops quality irrigated with treated wastewater. This research was conducted on a maize field near the wastewater treatment plant in Shahr-e-kord in summer،2011. Plots were arranged in a randomized complete block design in 3 replications and 2 treatments، well water (W1) with fertilizer and effluent (W2). At the end of growth season، soil samples were collected from depth of 0-5 and 5-15 cm and plant samples consisting of old and new leaves and seeds were collected for bacteriological analysis. According to bacteriological analysis، total number of positive lactose bacteria، total and fecal coliforms in depth of 0-5 cm was 42% more than depth of 5-15 cm. In the case of old leaves، total number of coliform and fecal coliform was 88 and 40 MPN/100 mL respectively. Moreover، for new leaves، it was 38 and 2 MPN/100 ml respectively. According the results، number of indicator bacteria in soil is decreased (about 35%) by passing time.