The use of treated gray wastewater for irrigation of rainfed olives in the West Bank

Abstract EN

Three levels of treated gray wastewater irrigation application to ‘Nabali’ olive tree cultivar (20, 25 and 30 cubic meters per tree) were evaluated and compared to fresh water application.

Irrigation effects were also compared to non irrigation through observing a control treatment.

The gray wastewater treatment system included an anaerobic gravel filter and a trickling gravel filter in addition to sand filtration.

Results of the experiment showed that supplementary irrigation of olive trees improved the yield and the vegetative growth.

High levels of water application (30 cubic meters per tree) significantly increased olive fruit production, number of shoots and length of shoots.

Also higher water applications (25 and 30 cubic meters per tree) increased the oil content of fruits.

However, irrigation applications did not significantly affect oil acidity and refractive index.

Treated gray wastewater application improved the vegetative growth of olives when compared to fresh water application.