On the ecology and nutritional value of two <em>Echinochloa species</em> (<em>Echinochloa colona</em> and <em>Echinochloa stagnina</em>) in Egypt

Abstract

In arid and semi-arid countries, where drought prevails together with population growth and limited food resources led to the search for non-conventional alternatives resources for food or feed. In the present study, the ecology, phytochemical composition, and nutritional value of two Echinochloa species (Echinochloa colona (L.) Link and E. stagnina (Retz.) P. Beauv.) collected from the canal banks of the Nile Delta, Egypt were investigated. The soils of E. stagnina had the highest values of moisture content (24.35%), water holding capacity (45.85%), pH (8.12), electric conductivity (5 dsm-1), chloride (1.15%), sulphates (0.95%), organic carbon (2.52%) and Na+ (66.78 mgkg-1). The cover percentages of E. stagnina showed positive significant correlations with water-holding capacity, organic carbon, pH, EC, Na but negative correlations with sand-fraction and sulphates. The shoot of E. stagnina had the highest values of moisture (11.20%), fibers (27.65%), crude proteins (6.90%), total carbohydrates (70.36%), but the shoot of E. colona had the highest contents of total fats (2.80%) and digestible carbohydrates (43.18%). The shoots of E. stagnina had the highest values of flavonoids (6.88 mg g-1 dry weight), alkaloids (5.66 mg g-1 dry weight), tannins (18.23 mg g-1 dry weight), saponins (1.99 mg g-1 dry weight) and total phenols (33.09 mg g-1 dry weight). Regarding nutritional status, E. colona had the highest total digestible energy (60.55%) and nutritive value (11.11%) while E. stagnina had the highest caloric value (219.72 kcal/100 g dry matter) and potential energy (315.21 kcal/100 g dry matter). The two Echinochloa grass are rich-source in nutrients and showed a great energy value. Therefore, the studied grasses are candidates as feed for livestock or as supplementary feed but after detailed toxicological studies.