A comparative study was carried out to evaluate the effects of two water irrigation sources on the qualityand microbiological safety of tomato plants and fruit, and on the microbiological soil properties: irrigationwith groundwater (GW) and with treated agro-industrial wastewater (TW). In a field experiment insouthern Italy (Apulia region), the physico-chemical characteristics of the irrigation waters and the fruitquality parameters were determined. Escherichia coli, fecal Enterococci and Salmonella spp. were alsomonitored in the irrigation waters, tomato plant and fruit, and root-zone soil. Bacteriological analysis fortotal heterotrophic counts (THCs) were determined for plant, fruit, and soil samples. The irrigation watersource did not significantly affect yield quantitative traits. However, with GW, the marketable fruit yieldwas higher than with TW (∼82 vs. ∼79 Mg ha−1, respectively). For both irrigation treatments, the mostimportant qualitative parameters that characterize the processing tomato fruit (i.e., dry matter content,pH, soluble solid content, color parameters) were in agreement with reports in the literature. For themicrobiological results, the mean levels of E. coli and fecal Enterococci were 4408 and 3804 CFU 100 ml−1,respectively, for TW (above the Italian guidelines for TW re-use). For the tomato plant and fruit, no E. coliisolated in either, and fecal coliforms and THC were not influenced by the irrigation waters (P > 0.05).Total bacterial enumeration by quantitative PCR was lower in soil irrigated with GW, than TW (3.69 vs.4.02, ×106, respectively). Moreover, soil microbial community patterns substantially differed betweenthe two water treatments. These data show that while fecal indicators are not affected, the communitycomposition and dynamics of the whole bacterial population in soil is influenced by the different qualitiesof these waters used for irrigation.
Treated agro-industrial wastewater irrigation of tomato crop: Effects on qualitative/quantitative characteristics of production andmicrobiological properties of the soil
GATTA, GIUSEPPE;LIBUTTI, ANGELA;GAGLIARDI, ANNA;BENEDUCE, LUCIANO;DISCIGLIO, GRAZIA;TARANTINO, EMANUELE
2014-01-01
Abstract
A comparative study was carried out to evaluate the effects of two water irrigation sources on the qualityand microbiological safety of tomato plants and fruit, and on the microbiological soil properties: irrigationwith groundwater (GW) and with treated agro-industrial wastewater (TW). In a field experiment insouthern Italy (Apulia region), the physico-chemical characteristics of the irrigation waters and the fruitquality parameters were determined. Escherichia coli, fecal Enterococci and Salmonella spp. were alsomonitored in the irrigation waters, tomato plant and fruit, and root-zone soil. Bacteriological analysis fortotal heterotrophic counts (THCs) were determined for plant, fruit, and soil samples. The irrigation watersource did not significantly affect yield quantitative traits. However, with GW, the marketable fruit yieldwas higher than with TW (∼82 vs. ∼79 Mg ha−1, respectively). For both irrigation treatments, the mostimportant qualitative parameters that characterize the processing tomato fruit (i.e., dry matter content,pH, soluble solid content, color parameters) were in agreement with reports in the literature. For themicrobiological results, the mean levels of E. coli and fecal Enterococci were 4408 and 3804 CFU 100 ml−1,respectively, for TW (above the Italian guidelines for TW re-use). For the tomato plant and fruit, no E. coliisolated in either, and fecal coliforms and THC were not influenced by the irrigation waters (P > 0.05).Total bacterial enumeration by quantitative PCR was lower in soil irrigated with GW, than TW (3.69 vs.4.02, ×106, respectively). Moreover, soil microbial community patterns substantially differed betweenthe two water treatments. These data show that while fecal indicators are not affected, the communitycomposition and dynamics of the whole bacterial population in soil is influenced by the different qualitiesof these waters used for irrigation.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
