Forage yield and quality of barley-annual medic intercrops in semi-arid environments

On-farm production of protein is limited in most dairy farm operations in arid and semi-arid environments. Cereal-legume intercropping could be a viable option to obtain forage with higher protein content. A two-year experiment was conducted during 2009 and 2010 growing seasons in a loamy soil to determine whether intercropping pattern of barley (Hordeum vulgare L.) and annual medic (Medicago scutellata L.) could increase forage quality while producing sufficient amount of forage yield. The results showed that when number of rows in 50:50 replacement intercropping decreased from six rows of barley and six rows of medic (6B:6M) (strip intercropping) to 4B:4M, 2B:2M and 1B:1M, barley forage yield increased by 9, 18 and 24% due to a wavy canopy created by 1B:1M and 2B:2M cropping ratios. Land Equivalent Ratio (LER) was highest (1.19) when barley was intercropped with annual medic in 1B:1M arrangement indicating that 19% more area would be required by a sole cropping system to yield similar of intercropping system. The highest protein yield was also obtained from 1B:1M ratio. Pure stand of annual medic had the highest Crude Protein (CP) content (310.7 g kg-1 of DM) whereas sole cropping of barley had the highest Neutral Detergent Fiber (NDF) and Acid Detergent Fiber (ADF). When both forage yield and quality was considered, the intercropping of barley and medic with 1B:1M ratio was superior to any other ratios and can be recommended to farmers as an alternative to barley alone. Keywords: Annual medic; Barley; Crude protein; Forage; Intercropping; LER.