Effect of Variety and Seeding Rate on Establishment and Productivity of Alfalfa Sown in Autumn

Five alfalfa varieties (var.) were sown on 26 September, 1983 near Aleppo on clay or heavy clay soils, classified as Vertisols (FAO-system) or Chromoxerertic (Calcic) Rhodoxeralf (USDA-system). Irrigation was applied after planting to ensure uniform germination. Thereafter the study was conducted under supplementary irrigation. The parameters measured to estimate fresh weight (FW) and dry matter (DM) yields; plant height, ground cover and regrowth after cutting, indicated that winter-active var. ( Moapa 69, CUF 101 and Aleppo local ) resulted in better productivity than semi-dormant ( Paravivo ) and dormant ( Lebanon local ) varieties. The 2-years mean average FW yields were 70.2, 68.2, 65.2, 57.1 and 36.9 t/ha, or 16.2, 16.0, 15.5, 13.1 and 8.9 t/ha DM respectively. Forage yields were similar among the 12, 16 and 20 kg/ha seeding rates, indicating little justification for high seeding rates under good establishment conditions, even if a seeding-year yield is desired. In general, seeding rate had also no effect on plant population, which was reduced with time and towards the end of the tested period it became nearly similar and counted 137, 132 and 134 plants/m² according to the seeding rates respectively. Alfalfa yields were positively correlated with plant height, ground cover and regrowth after cutting. The highest yielding combination for FW and DM yields in Moapa 69 with 12 kg/ha seeding rate.