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This study aims at investigating the effects of lateral depth and water applied on E. coli transport and plant growth while applying secondary sewage effluent during the growing season of asparagus lettuce in greenhouse. The experiments were conducted with three lateral depths of 0 (D0), 10 (D1) and 20 cm (D2) below the soil surface along with three irrigation levels that were determined by pan coefficient of 0.6 (I1), 0.8 (I2) and 1.0 (I3). The results indicated that the fate of E. coli in the soil was influenced by the lateral depth and the elapsed time after irrigation ceased. Generally, the population of E. coli demonstrated a decreasing trend with the growing of asparagus lettuce. Specifically, for all treatments of D0, E. coli in surface 10 cm soil decreased from 50-60 CFU/g to less than 9 CFU/g in 20 days after irrigation ceased. Only 1.0 and 0.4 CFU/g of E. coli was detected on the leave surface of plants. For all treatments, no E. coli was detected on the surface of stems. The yield ranged from 42 to 51 t/ha and the subsurface drip irrigation treatments irrigated at a pan coefficient of 0.8 produced a higher yield.
