COMPARISON OF CONSERVATION TILLAGE SYSTEMS IN BARLEY-BASED CROPPING SYSTEMS IN NORTHERN SYRIA

Abstract

Yields of rainfed barley (Hordeum vulgare) for feed and forage in small-ruminant production systems in low-rainfall areas of North Africa and West Asia are limited by low and erratic water availability. Therefore, the testing of conservation farming techniques, effective in dryland systems elsewhere, is often suggested. Seven-year results from a typical site in northern Syria showed that zero-till (direct-drill) systems with cereal residue retention may marginally enhance soil moisture status, but the yield effect on barley, either monocropped or rotated with vetch (Vicia sativa), was small and non-significant. In the vetch–barley rotation, a small and fairly consistent benefit to vetch was observed, amounting to a 20% yield increase in vetch hay. Given smallholders' strong preference for barley and reluctance to grow vetch as an alternate crop, there is little in this result to encourage the promotion of zero-till conservation techniques in these farming systems.