Bio-Diverse Mixed Cropping System of Barley (Hordeum vulgare) and Wheat (Triticum aestivum) Land Races in the Central Highlands of Eritrea—A Review

Baley and wheat mixture is a normal cropping system practiced in the central highlands of Eritrea, which is barley based system. Grains are used for human consumption in the form of bread; kernels are also roasted or used for the production of local beverages. The straw is used as animal feed. The advantages of growing the mixture is due to higher total yield, better yield stability, better food quality, better animal feed and resistance to diseases and weeds. Farmers in Eritrea have optimised crop proportions, landrace combinations and crop management of the barley and wheat mixed cropping system. The crop ratio commonly used is 2 : 1 to barley and wheat. Some landraces combine better than other and these combinations are most widely grown. Farmers sow the mixtures from mid June to mid July. Harvesting is done when barley is fully dried and wheat becomes mature changing its canopy colour. Farmers will continue to grow these mixtures as long as agriculture is characterised by low input and a high risk of drought in these areas. Mixtures have played a significant role in on-farm conservation of landraces. The cropping system also provides a unique model for testing various relevant research questions relating to functionality of diversity.