Cultivation of rooted olive cuttings of cv. Cornicabra as a bioindicator for evaluating the application of different types of sewage sludge

摘要

This research entailed growing rooted olive cuttings for three months in the greenhouse where they were tested as a bioindicator for evaluating possible phytotoxicity in olive on applying two types of sludge - composted sludge and thermally dried dehydrated sludge - both of which were from the ERAR in Madrid. When the composted sludge was applied, significantly fewer cuttings had dried out by the end of the three-month trial compared with the thermally dried dehydrated sludge. The cuttings were more sensitive to the dehydrated sludge treatment. Study of the variation in the fresh weight of the cuttings and the length of new roots revealed significant differences (p < 0.05) between the 0-10 t ha~(-1) and 20-40 t ha~(-1) application rates in the case of the thermally dried dehydrated sludge. The application of the composted sludge caused an increase in organic nitrogen, which peaked at 80 t ha~(-1), thus demonstrating that the sludge is a source of organic nitrogen that can be assimilated by the olive tree, even during the early stages of development (cuttings).