Influence of Treated Wastewater on the Percentage of Protein Content during Fodder Intercropping

Abstract

This study aims to explore the potential use of treated wastewater in irrigating fodder crops and its effects on protein contents. A comparison of the protein contents in intercropped fodder plants irrigated with fresh water, and rainfall water, against those irrigated with treated grey water was performed under Palestinian climate conditions. Field experiments with different intercropping mixing ratios were carried out in 2017–2019 at the National Agricultural Research Centre in Palestine (NARC). Measurements of the nutritional value of each mixture specifically the protein contents were carried out to get the optimal and best conditions for preparing animal feed crops with three different water sources used. For alfalfa with vetch, the best result for protein percentages was (on average) obtained from the rain-fed experiment (17.1% protein) followed by the freshwater experiment (12.9% protein) and then by the treated grey-water experiment (12.6% protein). It appears that the best result for alfalfa with barley for protein percentages was (on average) obtained from the treated grey-water experiment (13.0% protein) followed by the freshwater experiment (11.1% protein) and then by the rain-fed experiment (10.5% protein). Statistical analysis of the data showed that percent protein for each specific mixing ratio resulted in significant differences in the protein % for the those irrigated with fresh water compared with the other types of water. The highest protein % was found to be for that irrigated with fresh water (31.9 for 10/90 alfalfa/barley ratio) followed by that irrigated with treated grey water (28.4 for 20/80 alfalfa/barley ratio) and then for the 30/70 ratio irrigated with treated wastewater (22.5%), and then for the 100/0 ratio of alfalfa/barley irrigated with rainwater (19.0). Overall, results of this study showed that cereal-legume intercropping irrigated with treated grey water can be used as a suitable management strategy for producing high-quality and high-quantity forage. Furthermore, the use of treated water can reduce the already strained demand on fresh water due to increase in population among other factors.