Soil Phytoparasitic Nematodes Suppression and Changes of Chemical Properties Determined by Waste Residues from Olive Oil Extraction

摘要

The effect of olive mill wastes soil amendments on phytoparasitic nematodes and on soil fertility was investigated in a field experiment in southern Italy (Apulia region). Fresh and composted olive pomace were distributed at 10 t/ha, 20 t/ha, 40 t/ha rates and raw sewage was supplied at 40 m~3/ha, 80 m~3/ha, 160 m~3/ha, 240 m~3/ha in a sandy soil (Castellaneta, province of Taranto) infested by Meloidogyne incognita. Untreated and 300 kg/ha granular fenamiphos treated soil were also used as control. Cantaloupe crop yield, soil nematode population and root infestation index were recorded. Soil fertility parameters, C and N contents, nitrates and ammonium, total organic, extracted and humified C, were also determined. The results obtained may suggest that incorporation of OWW into the soil results in a suppression of soil nematode populations and, at low initial soil infestation, also in a crop yield increase. On the other hand the soil system is positively affected by the increase of soil organic matter content; perhaps the incorporation into the soil of organic substances containing, as average, 40 % of C, can contribute to C sequestration and to reduce greenhouse effect.