Crop yield response to water - Cra

Lead AuthorAlemtsehay Tsegay(Mekelle University, Tigray,Ethiopia)Contributing AuthorsDirk Raes,Sam Geerts,Eline Vanuytrecht(KU Leuven University,Leuven, Belgium),Margarita Garcia-Vila(University of Cordoba,Cordoba, Spain),Berhanu Abrha(Mekelle University, Tigray,Ethiopia)AcknowledgmentsTheodore C. Hsiao(University of California,Davis,USA),Gabriella Izzi(formerly FAO,Land and Water Division,Rome, Italy; currently WBWashington, USA),Pasquale Steduto(FAO, Land and WaterDivision,Rome, Italy)Scientists contributingwith experimentalDATA and tests for thecalibration of AquaCroPReinout Reggers,Nikolaas Viaene,Willem Raes,Nele Delbecque,Hanne Van Gaelen(KU Leuven University,Leuven, Belgium)TefGeneral descriptionTef (Eragrostis tef [Zucc.] Trotter) is a C 4 annual grass (Holden, 1973;Hirut et al., 1989) also known as bunch grass, which originated anddiversified in Ethiopia (Vavilov, 1951). It is one of the most importantcereal crops in that country, ranks first in cultivated area among all annualcrops and occupies about 29 percent of the land devoted to cereals. Tefyield is quite low (averages around 1 tonne/ha or less), but accounts forabout 20 percent of the total cereal production (in most cases second tomaize) in Ethiopia. The trend there over the last decade is an increase incultivated area (about 25 percent) and a 45 percent increase in yield perhectare. Outside Ethiopia, tef is also traditionally grown in Eritrea, and to alesser extent in India.Tef is predominantly grown alone, though it is intercropped occasionally withoil crops such as rapeseed, safflower and sunflower or relay-cropped withmaize and sorghum (Seyfu, 1997). In Ethiopia, tef is often rotated with pulses,such as field pea, faba bean, chickpea, or oil crops like linseed depending onlocation and the type of soil. In most cases a 4 or 5-year rotation is common,with pulse/tef/tef, wheat or barley/pulse, and pulse/tef/tef/other cereal/pulse.Tef is predominantly produced as a staple food for local consumption and animportant cash crop for farm households. The grain is grounded into flour tomake a pancake-like local bread called Injera. It provides about two-thirds ofthe daily dietary protein intake for most Ethiopians (NRC, 1996). The proteincontent of the grain is about 9-11 percent, slightly higher than sorghum,maize or oats, but lower than wheat or barley. Tef is also appreciated as afodder crop, with nutritious straw preferentially given to lactating cows andoxen used for traction. Moreover, its straw is the preferred binding materialin Ethiopia for walls, bricks and household containers made of clay.Tef grain contains gluten lacking the gliadin fraction that causes coeliacdisease; therefore it can be consumed by gluten intolerant people. Theamino acids of protein in tef grain are fairly balanced. These propertiesmake tef an attractive potential crop for cultivation outside its traditionalareas. Countries like the United States, Canada, Australia, South Africa, andKenya began production of tef for different purposes, as a forage crop, asa component of porridges and pancakes, and as a thickener for soup andgravy, probably because tef flour imparts the product a short, stiff textureand a slight molasses-like sweetness.238crop yield response to water