Annual forage legumes in dryland agricultural systems of the West Asia and North Africa Regions: research achievements and future perspective
Forage legumes are vitally important to animal production in the dryland farming systems of the Mediterranean region. Of the diverse forage-legume species adapted to the Mediterranean climate, vetches, (Vicia spp.), chicklings (Lathyrus spp.), annual medics (Medicago spp), clovers (Trifolium spp.) and species of the Lupinus, Lotus, Onobrychis, Hedysarum and Ornithopus genera are considered to be the most agronomically important and economically valuable species for the region. Adoption of perennial self-regenerating medic (Medicago spp.) has been limited because of technical difficulties, but annual vetch (Vicia spp.) has the greatest potential as a viable animal-feed source and a rotation crop with cereals. Some forage legumes survive harsh conditions by their unique underground growth habit, for example, V. amphicarpa and Lathyrus ciliolatus. Efforts to improve forage legumes have been based on both management/ cultural factors and breeding. Research based on several long-term barley- and wheat-based rotation trials has demonstrated the viability of forage legumes, especially vetch, in the regions improved farming system. An additional benefit to such legumes is the enhancement of soil quality, that is, soil fertility, soil organic matter and soil physical properties. Thus, the development of forage legumes is essential to agricultural sustainability in the Mediterranean region and in other dryland cereal-growing areas of the world where grazing livestock is a dominant enterprise. To build upon the considerable research conducted on forages, intensified efforts are needed to develop locally adapted forage cultivars, to provide economic assessment of forages in cropping systems and to promote technology transfer at the farm and community level.