Abstract

Biosolids from urban water and fish farming wastes have increased in the last years in Chile. It has generated the compulsory necessity to look for alternatives for its final disposition, in such a way that it do not constitute risk for the health and environment. In the present study the effects on germination of lettuce seeds ere analyzed as a result of the application of this type of organic biosolids in an Andic cryofluvents, Patagonian degraded soil. Biosolids were added into the soil, the treatments were: urban sewage sludge (BU), pisciculture waste (BP) and fish lake-farming waste (BL) at different inputs rates: 25, 50, 75, 100 and 150 Mg ha-1. A control without addition was also included. Bioassays in lettuce (Lactuca sativa L.) were conducted for germination index (IG), length of the radicle and length of hypocotyl structure. The results indicated that there were significant differences (p< 0.05) among biosolids, where the highest values for IG, radicle length and hypocotyl length were for BL, followed by BP. On the contrary, BU always was below the control (although it showed an IG > 80%), where the rate of application of 150 Mg ha-1 presented the smallest bioindicators values and no development of the hypocotyls structure was observed