ARS | Publication request: FORAGE QUALITY AND WATER-USE EFFICIENCY IN NINE IRRIGATED PASTURE GRASSES UNDER AN IRRIGATION GRADIENT AND MULTIPLE HARVESTS

Submitted to: American Society of Agronomy Meetings
Publication Type: Abstract Only
Publication Acceptance Date: April 26, 2005
Publication Date: November 6, 2005
Citation: Jensen, K.B., Waldron, B.L., Peel, M., Robins, J.G. 2005. Forage quality and water-use efficiency in nine irrigated pasture grasses under an irrigation gradient and multiple harvests. American Society of Agronomy Meetings.

Technical Abstract: Water available for irrigating pastures in the western USA is often limited and varies widely across sites and seasons. Objectives were to determine the trends in crude protein (CP), neutral detergent fiber (NDF), in vitro true digestibility (IVTD), and water-use efficiency in creeping meadow foxtail (Alepecurus arundinaceus Poir.), meadow (Bromus riparius Rehm.) and smooth (B. inermus Leyss), smooth X meadow bromegrass hybrids, orchardgrass (Dactylis glomerata L.), tall fescue (Festuca arundinaceae Schreb.), perennial ryegrass (Lolium perenne L.), RS-hybrid (Elymus hoffmannii Jensen & Asay), and Matua bromegrass (B. willdenowii Kunth) at five irrigation levels and three harvests (early, mid-, and late season). Combined over water levels and harvests, smooth bromegrass had significantly higher CP concentrations (238 g/kg) and lower NDF concentrations (418 g/kg) than the other grasses. In vitro true digestibility was highest in perennial ryegrass (895 g/kg) and smooth bromegrass (893 g/kg). Forage quality in hybrids between smooth and meadow bromegrass was intermediate to the parents. Trends within water levels and harvests and intercharacter correlations will be presented.