Forage yield and stability of improved and local populations of alfalfa (Medicago sativa L.)

The improvement and use of high quality and productive cultivars are priority goals in alfalfa (Medicago sativa L.) farming and research in the country. This study was conducted using 32 alfalfa genotypes in a RCB design with three replications during 2012 and 2013 at Seed and Plant Research Institute (SPII), Karaj, Iran. In the first year of the experiment, two cuts and in the second year, four cuts (six cuts in total) were taken and recorded. The studied traits included fresh and dry forage yield, plant height at harvest time and stem number per square meter. The ANOVA results based on the split plot design in time showed a significant difference among cuts, genotypes, and genotype by cutting interaction. Mean comparisons of the cuts revealed that the second cut had the highest fresh and dry forage yield in both years. The genotypes of D203, D210, D207, D206 with average values of 3.34, 3.34, 3.33, and 3.31 (t ha-1 per cut), and Ranger with 2.21(t ha-1 per cut) had the highest and lowest means of forage dry yield, respectively. D207, D206, D203, D210 and LakLak genotypes had the lowest superiority index and D206, Galebani, D205, D207, Laklak, and D201 genotypes had the lowest Shukla’s stability variance, respectively. According to the obtained results of dry forage yield and the stability indices, the genotypes D206, D207 and LakLak were selected as the most stable and productive genotypes.