Comparison of Quantitative and Qualitative Traits of Different Forage Vetch Species Under Rain-Fed and Supplemental Irrigation Conditions

In order to study and compare quantitative and qualitative traits of different forage vetch species under rainfall and supplemental irrigation conditions، two seprate experiments (rainfall and supplemental irrigation conditions) were conducted of faculty of Agriculture، Lorestsn University، Iran، during 2008-2009. Three species and three plant densites were combined factorially based on a randomized complete block design in each experiment. The highest and the lowest fresh forage yield (14،930، 5729 kg/ha) were recorded under supplemental irrigation condition and 100 plant/m-2 for V. narbonensis and V. dasycarpa، respectively. The highest and the lowest dry forage yield (4027، 1260 kg/ha) were recorded under rainfall condition and 150 plant/m-2 for V. narbonensis and V. dasycarpa، respectively. The highest protein content (22. 62%) was found in V. dasycarpa under rainfall condition and 200 plant/m-2، Also the lowest protein content (17. 33%) was found in V. sativa under rainfall condition and 100 plant/m-2. The highest protein yield (817. 9 kg/ha) was found in V. narbonensis under supplemental irrigation condition and 150 plant/m-2، Also the lowest protein yield (267. 1 kg/ha) was found in V. dasycarpa under rainfall condition and 100 plant/m-2. The highest (NDF) Neutral Detergent Fibers (34. 73%) was found in V. sativa under rainfalll condition and 150 plant/m-2، Also the lowest NDF (26. 42%) was found in V. narbonensis under supplemental irrigation condition and 200 plant/m-2. The highest yield NDF (1172 kg/ha) was found in V. narbonensis under rainfall condition and 150 plant/m-2، Also the lowest yield NDF (361. 2 kg/ha) was found in V. dasycarpa under supplemental irrigation condition and 150 plant/m-2. Acording to results، protein content was clearly affected by species and plant density. As protein content increased، NDF descreased، in both experiments.